download pdf - Institut für Umweltphysik - Ruprecht-Karls-Universität ...

Institut für Umweltphysik und Arbeitsstelle Radiometrie
Annual Research Report
2006
Ruprecht-Karls-Universität Heidelberg
und
Heidelberger Akademie der Wissenschaften

Contents
1 Introduction/Overview of institute 7
2 Atmosphere and Remote Sensing 9
2.1 Tropospheric Research Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.1.1 Long term measurements of reactive halogen species, trace gases and aerosols
by Multi Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) . . 18
2.1.2 DOAS on board: trace gas measurements on CARIBIC flights . . . . . . . . . 19
2.1.3 Airborne Imaging DOAS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.1.4 Auto-MAX DOAS measurements for Tropospheric NO2 in Europe . . . . . . . 21
2.1.5 NOVAC - Network for Detection of Volcanic and Atmospheric Change . . . . . 22
2.1.6 Enhancement and improvement of the DOAS software DOASIS;
Development of the NOVAC database . . . . . . . . . . . . . . . . . . . . . . . 23
2.1.7 Long-Path-DOAS Measurements of VOCs and HOx precursors in Mexico City
during MCMA-2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
2.1.8 Long-Path-DOAS Measurements with new fibre optic set-up . . . . . . . . . . 25
2.1.9 Tomographic LP-DOAS measurements of 2D trace gas distributions in Heidelberg 26
2.1.10 DOAS measurements of iodine oxides in the framework of the MAP project . . 27
2.1.11 Applicability of light-emitting diodes as light sources for active DOAS measurements
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.1.12 Multi Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) of Trace
Gas and Aerosol Distributions . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.1.13 Third Generation DOAS Telescopes . . . . . . . . . . . . . . . . . . . . . . . . 30
2.1.14 Testing a new Near-IR Sensor for Detection of Methane . . . . . . . . . . . . . 31
2.2 Stratospheric Research Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
2.2.1 Observational constraints on stratospheric ozone loss cycles . . . . . . . . . . . 39
2.2.2 Is there inorganic gaseous iodine in the tropical UT/LS ? . . . . . . . . . . . . 40
2.2.3 Trend of stratospheric bromine . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
2.2.4 High precision measurement of the UV BrO absorption cross section . . . . . . 42
2.2.5 Photolytic lifetime of stratospheric N2O5 . . . . . . . . . . . . . . . . . . . . . 43
2.2.6 Measurement of upper tropospheric and lower stratospheric radicals by balloonand
aircraft-borne scanning limb DOAS . . . . . . . . . . . . . . . . . . . . . . 44
2.3 Radiative Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.3.1 2-D mapping of cloud parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 50
2.3.2 Field measurements of water continuum and water dimer absorption . . . . . . 51
2.3.3 Oxygen A-band measurements for solar photon path length distribution studies 52
2.4 Satellite Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
2.4.1 Satellite observations of Glyoxal . . . . . . . . . . . . . . . . . . . . . . . . . . 59
2.4.2 Development of a Radiative Transfer Forward Model . . . . . . . . . . . . . . . 60
2.4.3 Retrieval of cloud parameters using SCIAMACHY and GOME data . . . . . . 61
2.4.4 Analysis of GOME Observations for Anthropogenic SO2 Emissions over China 62
2.4.5 Vertical OClO and BrO profiles from SCIAMACHY limb measurements . . . . 63
2.4.6 New GOME-Retrieval for Formaldehyde (HCHO) using daily mean Earthshine
Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
2.4.7 Radiative Transfer Modeling by Monte Carlo method for SCIAMACHY limb
geometry in the UV/VIS spectral range . . . . . . . . . . . . . . . . . . . . . . 65
2.4.8 Satellite observations of global water vapor trends 1996 - 2003 . . . . . . . . . 66
2.4.9 MAXDOAS observations on board the research vessel Polarstern . . . . . . . . 67
3

4 CONTENTS
2.4.10 Satellite monitoring of different vegetation types by differential optical absorption
spectroscopy (DOAS) in the red spectral range . . . . . . . . . . . . . . . 68
2.5 MarHal - Modeling of marine and halogen chemistry . . . . . . . . . . . . . . . . . . . 73
2.5.1 Modeling iodide – iodate speciation in atmospheric aerosol . . . . . . . . . . . 76
2.5.2 The Potential Importance of Frost Flowers for Ozone Depletion Events - A
Model Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
2.5.3 Modeling organic surface films on Atmospheric Aerosol Particles and their Influence
on Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
2.5.4 Importance of the surface reaction OH + Cl − on sea salt aerosol for the chemistry
of the marine boundary layer - a model study . . . . . . . . . . . . . . . . 79
2.6 Carbon Cycle Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
2.6.1 Top-down assessments of the regional H2 soil sink strength from continuous
atmospheric observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
2.6.2 Inferring high-resolution fossil fuel CO2 records at continental sites from combined
14 CO2 and CO observations . . . . . . . . . . . . . . . . . . . . . . . . . 85
2.6.3 Carbon cycle constraints derived from the interhemispheric ∆ 14 C difference . . 86
2.6.4 Investigating the soil sink of molecular Hydrogen (H2) . . . . . . . . . . . . . . 87
2.6.5 Observation of δ 13 C and δD in atmospheric methane and implementation of a
methane module to the GRACE model . . . . . . . . . . . . . . . . . . . . . . 88
3 Terrestrial Systems 91
3.1 Soil Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
3.1.1 Unstable Gravity-driven Fingering Flow in Unsaturated Porous Media . . . . . 97
3.1.2 Novel Evaporation Experiment to Determine Soil Hydraulic Properties . . . . . 98
3.1.3 Physical processes in the capillary fringe . . . . . . . . . . . . . . . . . . . . . . 99
3.1.4 Extension of the Grenzhof test site for conducting hydrogeophysical investigations
of water flow and solute transport at the field scale . . . . . . . . . . . . . 100
3.1.5 Installation of three soil and weather monitoring stations in permafrost soils on
the Qinghai–Tibet Plateau . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
3.1.6 Investigation on the applicability of remote sensing in surface moisture studies 102
3.1.7 Simulation of Ground Penetrating Radar Measurements over Multi-Layered Materials
using a Plane Wave Approach . . . . . . . . . . . . . . . . . . . . . . . . 103
3.2 Ice and Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
3.2.1 Radiocarbon measurement in ice . . . . . . . . . . . . . . . . . . . . . . . . . . 108
3.2.2 Climate significance of stable water isotope records from Alpine ice cores. . . . 109
3.2.3 Dissolved organic carbon (DOC) in glaciers: recent temporal changes and natural
levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
3.2.4 Progress in developing novel tools for Antarctic ice core research . . . . . . . . 111
4 Aquatic Systems 115
4.1 Groundwater and Paleoclimate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
4.1.1 A tracer study of paleoclimate and groundwater recharge in the North China
Plain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
4.1.2 Dating young groundwater in the North China Plain . . . . . . . . . . . . . . . 122
4.1.3 A multi tracer study to investigate the groundwater in the Odenwald region . . 123
4.1.4 Noble gas measurements on fluid inclusions in speleothems . . . . . . . . . . . 124
4.1.5 Gas partitioning in groundwater . . . . . . . . . . . . . . . . . . . . . . . . . . 125
4.1.6 Laboratory and field experiments on the formation of excess air in groundwater 126
4.1.7 Excess air formation at an artificial recharge site . . . . . . . . . . . . . . . . . 127
4.1.8 Collecting dissolved gases in water by diffusion samplers . . . . . . . . . . . . . 128
4.2 Lake Research (Limnophysics) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
4.2.1 Empirical mode decomposition: A tool to analyse time series . . . . . . . . . . 133
4.2.2 Hydrology and vertical transport of meromictic mining lakes traced with SF6
on the background level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
5 Small-Scale Air-Sea Interaction 137
5.1 Small-Scale Air-Sea Interaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
5.1.1 Gas Exchange Measurements: The Transition of the Boundary Conditions from
a Flat to a Wavy Water Surface . . . . . . . . . . . . . . . . . . . . . . . . . . 144
5.1.2 Gas exchange rates by LIF imaging of O2 concentration boundary layer . . . . 145
5.1.3 Water flow measurements in environmental and biological systems . . . . . . . 146

CONTENTS 5
5.1.4 Measuring depth dependent concentration profiles via fluorescent pH-indicator 147
5.1.5 3D fluid flow measurement close to free water surfaces . . . . . . . . . . . . . . 148
5.1.6 Small-scale turbulence in the sea-surface microlayer . . . . . . . . . . . . . . . 149
5.1.7 Measurement of short wind waves . . . . . . . . . . . . . . . . . . . . . . . . . 150
5.1.8 Spectroscopic Techniques for Gas-Exchange Measurements . . . . . . . . . . . 151
6 Forschungsstelle “Radiometrie” of the Heidelberger Akademie der Wissenschaften155
6.1 Forschungsstelle ”Radiometrie” of the Heidelberger Akademie der Wissenschaften . . . 157
6.1.1 Modelling growth and isotopic composition of stalagmites . . . . . . . . . . . . 160
6.1.2 A precisely dated climate record for the last 9 kyr from three high alpine stalagmites,
Spannagel Cave, Austria . . . . . . . . . . . . . . . . . . . . . . . . . 161
6.1.3 Measurement of 231 Pa in deep-sea sediments via ICP-MS and AMS . . . . . . . 162
6.1.4 Ghost Resonance in Glacial Climate . . . . . . . . . . . . . . . . . . . . . . . . 163
6.1.5 Dating and interpretation of climate proxies for three Holocene stalagmites from
the South of Chile (Patagonia) . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
6.1.6 14 C in speleothems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
6.1.7 Precise dating of D/O-Events on a stalagmite from Socorta Island (Indian Ocean)166
6.1.8 Trace element mapping of speleothems . . . . . . . . . . . . . . . . . . . . . . . 167
6.1.9 U-series dating and paleoclimatic interpretation of the stable isotope profile of
stalagmite ER76 from Grotta di Ernesto, Italy . . . . . . . . . . . . . . . . . . 168
6.1.10 Kinetic Fractionation of Stable Isotopes in Speletothems - Laboratory Experiments169
6.1.11 231 Pa/ 235 U-Dating of fossil corals with AMS . . . . . . . . . . . . . . . . . . . 170
6.1.12 Reconstruction of the geomagnetic field strength over the past 300.000 years
derived from 10 Be data of deep sea sediments from the North and South Atlantic
Ocean . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Bibliography 177

6 CONTENTS

Introduction
In Heidelberg, environmental physics continuously developed since the 1950s from the application of
nuclear physics methods to environmental research, mainly driven by Otto Haxel. In 1975, this led to
the foundation of the Institut für Umweltphysik (Institute of Environmental Physics), the first of its
kind in Germany, in the Fakultät für Physik und Astronomie with Karl-Otto Münnich as its founding
director.
From the start, the IUP focused on the underlying physics of a wide spectrum of environmental processes
and less on specific applications in atmospheric sciences, soil sciences, hydrology, or oceanography.
This turned out to be a major strength and it continues to distinguish the IUP from other large
environmental research institutes. With this focus, the IUP attains great flexibility in its methods
and is able to provide an environment where classical divisions between systems and disciplines can
be overcome. For instance, we investigate boundary layers between compartments which determine
the soil-atmosphere and ocean-atmosphere interactions. This direction of research is also adopted
by large international programs, like the International Geosphere Biosphere Project (IGBP), which
in recent times focus increasingly on investigation of interaction between compartments of the Earth
system. With its firm rooting in physics, the IUP sees itself in an excellent position to recognize and
investigate system properties of our environment and the interplay of its subsystems (atmosphere,
cryosphere, soil, groundwater, oceans,. . . ).
The IUP is a strongly experiment-oriented institution. Our current major fields of research are:
• physical foundations of climate research (budgets of greenhouse gases, oxidation capacity of the
atmosphere, radiation in the atmosphere),
• consequences of global change on central cycles in the earth system (water, carbon), and
• reconstruction of paleoclimate from a variety of environmental archives.
Our spectrum of methods still contains those developed from nuclear physics inheritance, specifically
the analysis of 14 C and various stable isotopes including noble gases. In addition, we employ an
array of new techniques like spectroscopy (of the atmosphere) and imaging spectroscopy, remote
sensing from ground-, air-, and space-borne platforms, time series analysis, as well as experiment- and
process-oriented modeling and simulation.
This report gives a snapshot of the research performed at the IUP by diploma students, doctoral
students, and senior scientist. It is intended as a comprehensive but concise overview for the members
of the institute as well as for the scientific community.
7

Atmosphere and Remote Sensing
2.1 Tropospheric Research Group . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.2 Stratospheric Research Group . . . . . . . . . . . . . . . . . . . . . . . . . 35
2.3 Radiative Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.4 Satellite Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
2.5 MarHal - Modeling of marine and halogen chemistry . . . . . . . . . . . 73
2.6 Carbon Cycle Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
9

Overview
Summary
Atmospheric research at the IUP (headed by U. Platt) concentrates on the physical and chemical
properties and composition of the atmosphere related to the global climate system as well as on processes
governing the oxidation capacity of the atmosphere. Central topics are reactive halogen species
in the troposphere, their release mechanisms, abundance, and influence on the oxidation capacity as
well as other free radical cycles in the stratosphere and troposphere, fundamental research related to
scattering and absorption of short-wave radiation transport in the atmosphere, and on the abundance
and role of trace and greenhouse gases in atmospheric chemistry and in the climate system. Main
tools of our research are spectroscopic observing systems on global, continental and regional scales
relying on sophisticated surface-, aircraft-, and balloon- based as well as space-borne remote sensing
techniques.
Observations are integrated in modelling studies of marine and stratospheric photochemistry with a
particular focus put on the chemistry of halogens, atmospheric radiation transport, and on global,
regional and trajectory models of source and sink processes of greenhouse gases.
Central topics include:
• Atmospheric composition and links to human health
• Radiation transfer processes and links to climate
• Tropospheric halogen species and their role in the oxidation capacity of the atmosphere
• Stratospheric ozone as influenced by halogen and nitrogen species
• Sources and sink processes as well as isotopic abundances of greenhouse gases
• Global observing systems
• Further development of remote sensing techniques (e.g. tomographic techniques)
A detailed description of the different topics is presented in the individual group reports.
Atmospheric composition and links to human health
Studies of radical processes in tropospheric chemistry were performed, free radicals determine the
oxidation capacity of the troposphere, i.e. the capacity of the atmosphere to clean itself from natural
and anthropogenic pollutants. Scientific objectives include studies of the processes governing the
oxidation capacity of the troposphere. In particular the release and activation processes of reactive
halogen species in the troposphere. Studies in this year centred on the following questions:
• The abundance of reactive halogen species (BrO, IO, OIO, I2) in the marine boundary layer in
coastal regions.
• The abundance of reactive halogen species (BrO, IO) and related compounds over the open
ocean.
• The abundance of reactive halogen species, in particular BrO, and related species like NO2, NO3
and CH2O in the free troposphere
• The rate of volcanic emissions of SO2 and reactive halogen species, e.g. BrO, ClO, OClO.
• The chemical evolution of reactive halogen species in volcanic plumes, with particular emphasis
on the processes after O2 and O3 mixes into the originally reducing plume.
• The tomographic determination of the 2D-distribution of air pollutants over the city of Heidelberg.
The different topics are described in detail in the individual group reports.
11

12 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Future Work
Future work will encompass
1. Continued establishment of a large network of ground based remote sensing instruments to
quantify volcanic emissions, which will provide the first comprehensive study of volcanic sulfur
and halogen emissions (EU-project NOVAC).
2. Further study of the marine halogen chemistry with particular emphasis on iodine-particle formation
(EU-project MAP), nonlinear chemistry, and emission ”hot spots”.
3. Spectroscopic studies of atmospheric particles will be performed within a large long-term intercomparison
exercise (EU-project ICARTT).
4. Study of the inter-annual variation of the solar radiation field including 2-D imaging spectroscopy
of the radiative properties of the atmosphere with a particular focus on the radiative properties
during the life cycle of individual clouds (DFG Forschergruppe ’life cycles of clouds’)
5. Using novel ballon-based instrumentation (Mini-DOAS), the time-dependence of ozone destroying
radicals (BrO, and OClO) and inferred reactive chlorine will be investigated from which
conclusions on the most important loss reactions for stratospheric ozone in polar winter can be
drawn.
6. Investigation of the transport and photochemical processes at the major entrance of tropospheric
air into the stratosphere, i.e. the tropical upper troposphere layer/lowermost stratosphere
(TTL/LMS). Conclusions will be drawn on the ozone depletion potential of major manmade
and naturally emitted ozone destroying chemicals passing the TTL/LMS (EU-project
SCOUT-O3).
7. Study of the European carbon balance and in particular the fossil fuel CO2 contribution (EUproject
CarboEurope-IP).
8. Within the carbon system, investigation of independent constraints on global carbon exchange
as derived from long-term high precision 14 CO2 observations in combination with model studies
(DFG project, Atmospheric 14 C).
9. Investigation of the continental European hydrogen budget (in particular the anthropogenic
source and the soil sink) using continuous and aircraft observations over Europe and Siberia
(EUROHYDROS and TCOS II, submitted EU proposals). Instrument development will be
continued, a particular topic being preparation for the new German research aircraft HALO. In
this context we are developing novel instruments based on imaging and near-IR spectroscopy.
Literature
A total of 52 peer reviewed manuscripts where accepted by or appeared in scientific journals. Members
of the institute were invited to give one presentation on topics related to atmospheric research at
scientific conferences
Diploma and Doctoral Theses
A total of 1 Diploma theses and 6 Doctoral theses on topics related to atmospheric research were
completed in the reporting period.

2.1. TROPOSPHERIC RESEARCH GROUP 13
2.1 Tropospheric Research Group
Group members
Prof. Dr. U. Platt, Group leader Atmosphere
Jessica Balbo, Diploma Student
Dipl. Phys. B. Dix, Ph.D. Student
Marleen Gillmann, technician
Dr. Klaus-Peter Heue, Post-Doc
M.Sc. Ossama Ibrahim, Ph.D. Student
Dipl. Phys. Christoph Kern, Ph.D. Student
Dipl. Phys. Thomas Lehmann, software development
Dipl. Phys. André Merten, Ph.D. Student
Jan Meinen, Diploma Student (Univ. of Ilmenau, jointly with T. Leisner)
Dr. C. Peters, Post Doc
Dipl. Phys. Denis Poehler, Ph.D. Student
Dipl. Phys. Katja Seitz, Ph.D. Student
Susanne Lindauer, technician
Dipl Phys. Roman Sinreich, Ph.D. Student
Holger Sihler, Diploma Student (University of Jena)
Thorsten Stein, Diploma Student
Jens Tschritter, Diploma Student
Markus Woyde, Diploma Student
Abstract
Tropospheric research in the IUP concentrates on the processes governing the oxidation capacity of the
atmosphere. Of particular interest are release processes of reactive halogen species from a multitude of
sources (marine biology, sea spray, volcanoes, etc.) into the troposphere. Consequences for the state
of the troposphere are studied together with the other atmospheric subgroups and within national
and international collaborations.
Scientific Objectives
include studies of the processes governing the oxidation capacity of the troposphere. In particular the
release and activation processes of reactive halogen species in the troposphere. The questions studied
in this year centred on the following questions:
• The abundance of reactive halogen species (BrO, IO, OIO, I2) in the marine boundary layer in
coastal regions and over the open ocean.
• The abundance of reactive halogen species, in particular BrO, and related species like NO2, NO3
and CH2O in the free troposphere.
• The rate of volcanic emissions of SO2 and reactive halogen species, e.g. BrO, ClO, OClO.
• Modelling and observational studies of the chemical evolution of reactive halogen species in
volcanic plumes, in particular with respect to processes after mixing of O2 and O3 into the
originally reducing gases emanating from the lava.
• Determination of two-dimensional trace gas distributions.
Overarching topic
Studies of radical processes in tropospheric chemistry, the oxidation capacity of the troposphere, i.e.
the capacity of the atmosphere to clean itself from natural and anthropogenic pollutants. The role of
aerosol particles in atmospheric radiation.
Background
Free radicals play a pivotal role in atmospheric chemistry. Despite their exceedingly small concentration
(mixing ratios around < 10 −12 to about 10 −10 ), these species are the driving force for most
chemical processes in the atmosphere. While the role of hydrogen radicals (OH, HO2) is relatively
well studied and largely understood, other free radicals like halogen atoms or halogen oxides (e.g. IO,
BrO, ClO) have been neglected until recently. In particular, at the levels suggested by the available

14 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
measurements tropospheric halogen species can have profound effects on many aspects of tropospheric
chemistry, these include:
(1) Reactive halogen species, and in particular reactive bromine and iodine can readily destroy tropospheric
ozone, which can have a multitude of consequences, both chemical and climatic (e.g. [Roscoe
et al. , 2001], [Platt & Hönninger, 2003]). Catalytic ozone destruction essentially occurs by two distinct
reaction cycles. Either (I) involving self reaction of halogen oxide radicals with other halogen oxide
radicals (XO+XO or XO+YO) or (II) reaction of halogen oxides with hydrogen radicals XO+HO2):
leading to the net result:
O3 + O3 → 3O2
Cycle (I) has been identified as the prime cause for polar boundary layer ozone destruction (e.g.
[Barrie & Platt, 1997]). Since the rate of ozone destruction is usually proportional to the square of
the halogen oxide concentration, cycle (I) ineffective at low XO levels usually found in mid-latitude
coastal areas. At low RHS levels, however O3 destruction takes place by reaction cycle (II), here the
rate of O3 destruction is linearly dependent on the XO concentration.
(2) An important side effect of cycle (II) the conversion of HO2 to OH and thus a reduction of the
HO2/OH ratio, in particular at low NOX levels. At a given photochemical situation (O3, H2O levels,
insolation) the presence of BrO or IO will therefore increase the OH concentration. It is interesting
to note that both effects have been observed in the upper troposphere (e.g. [Wennberg et al. , 1998]).
(3) The reaction of XO with NO leads to conversion of NO to NO2 and thus to an increase of the
Leighton ratio (L=[NO2]/[NO]). An increase in L is thus usually regarded as an indicator for photochemical
ozone production (due to the presence of RO2 (R = organic radical)) in the troposphere.
However, as already noted by [Platt & Janssen, 1996] an increase in L due to halogen oxides will not
lead to O3 production.
(4) A more subtle consequence of reactive halogen species for the ozone levels in the free troposphere
is due to the combination of the above effects (2) and (3) as pointed out by [Stutz et al. , 1999]:
Photochemical ozone production in the troposphere is limited by the reaction
(2.1)
NO + HO2 → NO2 + OH (2.2)
However, the presence of reactive bromine will reduce the concentrations of both educts of the above
reaction and thus reduce the NOX - catalysed ozone production.
(5) Heterogeneous reactions of bromine species (i.e. HOBr) with (sea salt) chloride can lead to the
release of Cl-atoms. This process constitutes a Br catalysed chlorine activation. Since Cl-atoms are
highly reactive, this process directly enhances the oxidation capacity of the troposphere, see e.g. [Platt
et al. , 2004].
(6) Gas-phase iodine species (like IO, OIO or HOI) may facilitate transport of I from the coast to
inland areas and thus contribute to our iodine supply [Cauer, 2004], [Cox et al. , 1999].
(7) Deposition of mercury was found to be enhanced by the presence of reactive bromine species in
particular in polar regions (e.g. [Barrie & Platt, 1997]), this process appears to be linked to the
oxidation of Hg0 to Hg(II), likely by reaction with BrO [Lindberg et al. , 2002].
(8) The reaction of BrO with dimethyl sulfide (DMS) might be important in the unpolluted remote
marine boundary layer where the only other sink for DMS is the reaction with OH radicals (e.g. [von
Glasow et al. , 2004], [von Glasow & Crutzen, 2004]).
(9) Iodine species have been shown to be involved in particle formation in the marine BL ([Leck &
Bigg, 1999], [Hoffmann et al. , 2001], [O’Dowd et al. , 2002], [Burkholder et al. , 2004]).
(10) Evidence is accumulating (see e.g. [Platt & Hönninger, 2003]) that there is a wide-spread ”background”
level of BrO radicals in the free troposphere, due to the processes described under (1)-(5)
and (8) above there might be an important effect of reactive halogens on the global tropospheric
chemistry as summarised by [von Glasow et al. , 2004].
Main methods
include the experimental determination of the halogen oxide distribution and the distribution of related
species in several compartments of the troposphere:
1) The marine boundary layer in coastal regions (Mace Head, Ireland).
2) The open ocean.
3) The free troposphere.
4) Volcanic emissions (contents of reactive halogen species, e.g. BrO, ClO, OClO in volcanic plumes).

2.1. TROPOSPHERIC RESEARCH GROUP 15
The measurements are made by Differential Optical Absorption Spectroscopy (DOAS), which allows
the detection of many atmospheric trace gases at a sensitivity in the ppt - range (i.e. at mixing
ratios down to 10-12ppt). For studies in the different compartments a series of variants of the technique
were applied:
1) Studies in the marine boundary layer were performed by active DOAS (i.e. using artificial light
sources), which allows also nighttime studies, as well as by passive ”Multi-Axis” DOAS (MAX-DOAS).
2) Ship-borne measurements in the open ocean relied on MAX-DOAS observations requiring relatively
little logistic prerequisites and allowed unattended operation.
3) Aircraft-based measurements in the free troposphere are also based on passive MAX-DOAS observations,
while ground based observations (at the Zugspitze) employ active DOAS measurements.
4) Aircraft-based measurements of pollution plumes employed the newly developed Airborne Imaging-
DOAS technique.
5) Observation at volcanoes were made by passive MAX-DOAS and by the novel Imaging-DOAS
technique recently developed in our group.
In addition to the field campaigns a number of projects is aimed at technological improvements of
the DOAS technology. Activities included studies on the reduction of the optical noise [Platt, 1994]
by the use of optical fibers and mode mixers to connect light source and transmitting telescope, the
use of Light Emitting Diodes as DOAS light sources, and development of novel techniques for the
inversion of MAX-DOAS measurements to derive the aerosol optical density as well as the vertical
distribution of trace gases in the lower atmosphere.
Main activities
A large number of field campaigns were conducted:
• Expeditions to the volcanoes Etna (Italy) and ... to study emission of halogen oxide radicals
and SO2.
• Studies of nitrate radicals and related species at the Schneeferner Haus (Zugspitze, Germany)
• Ship expedition (on RV Polarstern) during ... to study the NO2, O3, and BrO from 52 o S to
72 o N.
• Studies of the oxidation capacity of the lower atmosphere in New England (USA) within the
framework of the ICARTT project.
• Participation in the CARIBIC - Project.
• Also world wide long-term measurements of halogen oxides and related species were performed
by the ”Heidelberg Ground-Based Network”.
• Transsects with Automobile based DOAS instruments were performed to study emission plumes
(e.g. from fire in southern England).
• Observation of the 2-dimensional trace gas distribution over the centre of Heidelberg using
tomographic - DOAS techniques.
• DOAS Measurements of VOCs and HOX precursors in Mexico City during the MCMA-2006
campaign.
A series of laboratory studies aimed at the improvement of the DOAS technique:
• Investigation of the suitability of LEDs as light sources for active DOAS measurements
• Development of a new quartz-fibre based technique for coaxial DOAS instruments, which promises
more compact and robust instruments.
• Development of the Airborne Imaging-DOAS technique.

16 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Funding
EUSAAR (EU)
NOVAC (EU)
MAP (EU)
IALSI (EU)
TURBAN (DFG)
DFG-HALO
SCIAMACHY validation (BMBF)
CARIBIC
Two Ph.D. students are funded through the International Max-Planck Research School on ”Experimental
Atmospheric Chemistry”.
Cooperation within the institute and with groups outside of the institute
Obviously there is close cooperation within the atmospheric groups. National and international cooperation
exists with the following groups:
Chalmers University, Gothenburg, Sweden (B. Galle)
Volcanic observatory Etna, Italy (M. Burton)
Max-Planck Institue for Chemistry, Mainz (J. Crowley, T. Wagner)
University of Mainz (Heumann)
University of Bayreuth (C. Zetzsch)
Institute for Physical Chemistry, University of Wuppertal (I. Barnes)
Alfred Wegener Institute for Polar Research, Bremerhafen
NOAA, Boulder (M. Trainer)
University of Cambridge (Oppenheimer)
Atmospheric Environment Sevice of Canada, Toronto, CDN (J. Bottenheim)
University of California, Los Angeles, USA (J. Stutz)
IfM-Geomar, Kiel (D. Wallace)
IfT Leipzig (Neuhaus)
Future Work
will encompass the establishment of a large network of volcanic stations to provide the first comprehensive
and quantitative study of volcanic sulfur and halogen emissions (EU-project NOVAC). Also
marine halogen chemistry will be studied, particular emphasis will be of iodine-particle formation (Euproject
MAP), nonlinear chemistry, and emission ”hot spots”. Spectroscopic studies of atmospheric
particles will be performed within a large long-term intercomparison exercise (EU-projcet ICARTT).
Instrument development will be continued, a particular topic being preparation for the new German
research aircraft HALO.
Peer Reviewed Publications
1. Allen et al. [2006]
2. Bobrowski et al. [2006a]
3. Bobrowski et al. [2006c]
4. Bruns et al. [2006]
5. Kern et al. [2006]
6. Frießet al. [2006]
7. Frins et al. [2006]
8. Hartl et al. [2006]
9. Leigh et al. [2006]
10. Mettendorf et al. [2006]
11. Wang et al. [2006]
12. Oppenheimer et al. [2006]

2.1. TROPOSPHERIC RESEARCH GROUP 17
Other Publications
1. Barkly et al. [2006]
2. Bobrowski & Platt [2006]
3. Bobrowski et al. [2006b]
4. Frieler et al. [2006]
5. Frieß& Platt [2006b]
6. Frieß& Platt [2006a]
7. Lee et al. [2006]
8. Louban et al. [2006]
9. Platt et al. [2006]
10. Sebastian et al. [2006]
11. Sinreich et al. [2006]
12. Simpson et al. [2006]
13. Stutz et al. [2006]
14. Xie et al. [2006]
Diploma Theses
1. Stein [2006]
PhD Theses
1. Bossmeyee [2006]
2. Hak [2006]

18 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.1.1 Long term measurements of reactive halogen species, trace gases and
aerosols by Multi Axis Differential Optical Absorption Spectroscopy
(MAX-DOAS)
Jessica Balbo (Udo Frieß, Ulrich Platt)
Abstract Two multi-axis DOAS instruments were set up at (1) the Global Atmospheric Watch
(GAW) site in Hohenpeissenberg, Germany, and (2) at the new SOLAS observatory on the island
of São Vicente, Cape Verde. The purpose of these long-term measurements is the investigation of
the tropospheric chemistry in polluted areas (Hohenpeissenberg) and in the remote marine boundary
layer (Cape Verde).
Figure 2.1: Mounting of Mini Max-Doas instruments on Hohenpeissenberg, Germany (left) and São
Vicente, Cape Verde (right)
Background Long-term observations of compounds
playing a key role in the atmospheric
chemistry are of great importance for the understanding
of the chemical processes occurring on
time scales ranging between minutes and years.
Anthropogenically emitted pollutants, such as
NOx and volatile organic compounds (VOCs)
have an impact on the tropospheric ozone budget
and can affect human health. On the other
hand, it is also important to study the remote
atmosphere in order to understand its chemical
behaviour in the absence of man-made emissions.
In recent years evidence has grown that halogen
compounds emitted by the ocean can have a severe
impact on the chemistry of the marine boundary
layer, and possibly also on the ozone budget and
thus climate on a global scale.
Methods and results Two multi-axis DOAS
instruments were installed with the purpose of
performing long-term measurements of atmospheric
trace gases. The first instrument has
been installed in August 2006 and is operated
in collaboration with the Deutsche Wetterdienst
at the Global Atmospheric Watch (GAW) Station
in Hohenpeissenberg, Germany (figure 2.1,
left). The GAW station is located about 60 km
south-west of Munich at an altitude of ≈ 1000 m.
Max-DOAS measurements performed at this location
will, depending on the wind direction, allow
to measure several important trace gases (NO2,
formaldehyde, nitrous acid) both in background
air and in polluted air masses originating from
Munich. The second long-term MAX-DOAS instrument
has been installed on the SOLAS observatory
on the island of São Vicente, Cape Verde
(figure 2.1, right). The main focus of these unique
measurements is the investigation of reactive halogen
chemistry in the subtropical marine boundary
layer based on measurements of BrO, IO, and possibly
OIO in a region where atmospheric measurements
are still very sparse.
Outlook/Future work The long-term measurements
in Hohenpeissenberg and on the Cape
Verde Islands are planned to be performed for
several years, allowing to investigate the tropospheric
chemistry both under polluted conditions
in central Europe and in the subtropical marine
boundary layer. The spectral analysis of the time
series from the two MAX-DOAS instruments is
currently under development and first results are
expected in early 2007.

2.1. TROPOSPHERIC RESEARCH GROUP 19
2.1.2 DOAS on board: trace gas measurements on CARIBIC flights
Barbara Dix (Udo Frieß, Thomas Wagner, Ulrich Platt)
Abstract CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an
Instrument Container) is an innovative project to study atmospheric processes on board a passenger
aircraft during long-distance flights. Besides in-situ measurements of various atmospheric compounds,
it also features a Multi-Axis DOAS instrument to detect specific trace gases.
Figure 2.2: The inlet pylon (h=0.5m) is mounted to the airplane’s lower body. Three small black
holes in the upper half indicate the position of the DOAS telescope entrances.
Background Halogen compounds and nitrogen
oxides have a significant impact on the global
ozone budget, e.g. reactive bromine and chlorine
compounds cause stratospheric ozone depletion.
A possible background of reactive bromine compounds
in the free troposphere would also have
a strong impact on the tropospheric ozone budget.
Therefore global measurements of tropospheric
compounds are of great interest.
Within the framework of CARIBIC, a new
DOAS (Differential Optical Absorption Spectroscopy)
instrument was built. Besides BrO, it
can also detect HCHO, OClO, HONO, O3, NO2,
water vapor, and O4.
Methods and results Airborne DOAS measurements
provide an excellent platform to study
the free troposphere globally. The CARIBIC
DOAS instrument is one of 21 instruments
mounted in a cargo container, that has been successfully
put into operation on a new long-range
Airbus (A340-600) of Deutsche Lufthansa. Since
May 2005 regular flights with fully automated
measurements are performed once a month. A
miniaturized telescope system, which was especially
designed to fit into the inlet pylon (see figure
2.2), collects UV-visible scattered sun light
from three different viewing directions (straight
down, 10 degrees above and below the horizon).
With this Multi-Axis technique the separation
of boundary layer, free tropospheric and stratospheric
columns is possible. Trace gases are identified
and quantified from their individual absorption
structures in recorded spectra.
Results show stratospheric columns of BrO,
NO2 and O3 as well as tropospheric water vapor
in the tropics. So far there where no enhanced
BrO levels detected in the free troposphere, perhaps
due to an evenly distributed background.
Enhanced levels of tropospheric NO2 and HCHO
during landing and take-off in big cities such as
Sao Paulo, Guanghzou (China) or Manila are seen
as expected due to anthropogenic pollution. During
several flights over South America and China
biomass burning plumes were seen and in one convective
pollution plume over China even HONO
could be detected. Measured columns of the oxygen
dimer O4 yield information on the radiative
transport.
Outlook/Future work Radiative transfer
modelling will be performed in order to extract
vertical columns for BrO, NO2 and O3 as well as
for characterizing the boundary layer upon landing
and take-off. Together with other CARIBIC
participants the questions of transport and chemistry
within plumes will be discussed and by spring
2007 a full year of flights from Germany to China
will provide the foundation for first statistics.

20 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.1.3 Airborne Imaging DOAS
Klaus-Peter Heue (Stephen Broccardo 2 , Stuart Piketh 2 , Ulrich Platt, Kristy Ross 3 )
2 University of Witwatersrand Johannesburg, 3 ESKOM, South Africa
Abstract Two dimensional distribution of a several trace gases were mapped by a ground based
imaging DOAS instrument build in 2003. Now a modified instrument for airborne measurements was
realised and first measurements were performed in a test campaign in the Highveld region South Africa
in October 2006.
N u m b e r o f p ix e l
5
1 0
1 5
2 0
2 5
D is ta n c e [m ]
0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 2 5 0 0 3 0 0 0 3 5 0 0
4 3 8 0 4 3 8 5 4 3 9 0 4 3 9 5 4 4 0 0 4 4 0 5 4 4 1 0 4 4 1 5 4 4 2 0
N u m b e r o f s p e c tru m
8 0 0
6 0 0
4 0 0
2 0 0
0
-2 0 0
-4 0 0
-6 0 0
-8 0 0
w in d d ire c tio n
flig h t d ire c tio n
Figure 2.3: NO2 SCD distribution below the aircraft close to the power station in Majuba, South
Africa, which is indicated by the circle (preliminary result).
Background In most atmospheric investigations
information about the two dimensional distribution
of tropospheric trace gases is highly desirable.
A typical use is the identification of source
areas, emission plumes, or the validation of chemical
transport models. In the past various attempts
have been made on different spatial scales, e.g.
DOAS tomography on local scales (10 km), or
satellite measurements on a global scale. We build
an instrument based on imaging spectroscopy to
map the 2D distribution of a series of relevant
trace gases including NO2, glyoxal, H2O, O4 and
BrO. It is installed on an aeroplane and observes
the local distribution with a spatial resolution of
100 m.
The Imaging DOAS instrument Lohberger
et al. [2004] consists of an imaging spectrometer
combined with a two dimensional detector
(i.e. a CCD camera) analysing sun-light backscattered
from the earth’s surface. The CCD camera
records the spectral information in one dimension
(x) and spatial information in the other dimension
(y) perpendicular to the aircraft’s flight direction.
The spectra are analysed using the DOAS technique
?, to retrieve the concentration integrated
along the light paths which is called slant column
densities (SCD’s). Thereby 2D-maps of the trace
gas’s SCD are recorded.
The newly build instrument was installed on
an Aero Commander (ZS-JRA) of the South
D is ta n c e [m ] a t g ro u n d le v e l
re la tiv e to th e p lu m b lin e
African Meteorological Service for a research campaign
in the Highveld (ZA) in early October 2006.
The instrument’s total field of view was 24.5 o (corresponding
to a swath width of e.g. 1900 m at
4400 m flight altitude above ground).
Methods and results First results are shown
in figure 2.3 depicting the recorded NO2 columns
when the aeroplane passed over a power station.
The prevailing wind (indicated by the arrow) blew
the plume across the flight track as it is clearly
visible in the reconstructed NO2 SCD map.
Outlook/Future work The existing instrument
has to be further improved until next spring
when the second part of the campaign will take
place.
In cooperation with the Anhui Institute of Optics
& Fine Mechanics (Hefei, China) new improved
instruments will be build and employed on
a high altitude research aircraft.
Meanwhile the construction of a more sophisticated
instrument for the new research aircraft
HALO (Gulfstream 550) has just begun.
Funding The measurements in South Africa
were funded by the South African electricity
supply company (Eskom). The instrument was
funded by the Institute.
2 ]
N O 2 S C D [1 0 1 6 m o le c /c m
2 2
2 0
1 8
1 6
1 4
1 2
1 0
8
6
4
2
0

2.1. TROPOSPHERIC RESEARCH GROUP 21
2.1.4 Auto-MAX DOAS measurements for Tropospheric NO2 in Europe
O. W. Ibrahim (Thomas Wagner, Torsten Stein and Ulrich Platt)
Abstract Detection and retrieval of Vertical Column Densities of tropospheric air pollutant trace gas
NO2 was carried on in industrial/traffic/urban areas in Europe. Measurements have been performed
using the Automobile Multi Axis Differential Optical Absorption Spectroscopy technique(Auto-MAX
DOAS)
Figure 2.4: Panel (A): The route of driving with Auto-MAX DOAS from Brussels (Belgium) to
Heidelberg (Germany). Panel(B):The Vertical Column Densities (VCDs) along the route retrieved
from these measurements.
Background Measurements of tropospheric
pollutant trace gases in urban and industrial areas
need a suitable spatial resolution. Although
Satellites and airplanes can perform tropospheric
columns measurements , their spatial resolution is
still of the order of several kilometers. The Automobile
Multi Axis Differential Optical Absorption
Spectroscopy technique (Auto-MAX DOAS) has a
more suitable spatial resolution (ranging between
few tens of meters and few hundred meters). Making
it an attractive tool for the measurements of
trace gases on the scale of cities. The Auto-MAX
DOAS fills the knowledge gap of tropospheric pollution
between the local scale of cities and regional
scale.
Methods and results The use of UV/Vis spectroscopy
with a miniature instrument installed on
a car roof enables the detection and quantification
of trace gases such as NO2, SO2, HONO,
and CH2O in the troposphere. The time resolution
of measurements is about 20-30 seconds and
the spatial resolution from this method is ranging
between tens of meters and a few hundred
meters depending on the actual integration time
and the driving speed of the car. The detection
limit of NO2 is about 1 ppb, depending on the
observation geometry. In contrast to in-situ techniques,
from continuous Auto-MAX DOAS observations
the integrated amount of trace gases (integrated
over the altitude) is derived. Here we
present the results of NO2 Vertical Column Densities
(VCDs) from Auto-MAX DOAS measurements.
Figure 2.4(A): the route of the Auto-MAX
DOAS when driving from Brussels (Belgium) to
Heidelberg (Germany), (B) The Vertical Column
Densities (VCDs) along the route retrieved from
these measurements. The VCDs retrieved by this
method can be used for comparison/evaluation of
satellite measurements over Urban areas with the
advantage of having a better spatial resolution
(i.e. the ability to see the gradients of the trace
gases within the satellite pixel).
Outlook/Future work Further improvement
of the Auto-MAX DOAS is planned for the near
future. This includes optimization of time resolution
and spatial resolution. The expected improvement
in time resolution will be achieved by
using a newer generation of spectrometers with
detectors (QE65000) with a higher quantum efficiency
(up to 90 percent) and a better light
throughput compared to the one used here. This
will reduce the total integration time (i.e.improve
the time resolution) by about one order of magnitude
which will also improve the spatial resolution
of the Auto-MAX DOAS.
Funding International Max Plank Research
School scholarship.
Main publications Under preparation.

22 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.1.5 NOVAC - Network for Detection of Volcanic and Atmospheric Change
Christoph Kern
Abstract A novel passive DOAS instrument was designed and built explicitly for the measurement
of volcanic emissions in the scope of the NOVAC project. The first measurements with the instrument
prototype were conducted at Mt. Etna, Sicily.
Figure 2.5: Left panel: example results of an SO2 flux measurement on Oct. 2, 2006 az Mt. Etna.
Each graph represents a MAX DOAS scan through the volcanic plume. The integral over the entire
scan yields the amount of SO2 in the plume cross section. By measuring the wind speed, the flux can
subsequently be derived. The photo on the right shows the measurement geometry.
Background NOVAC is an EU funded project
started in October 2005 with the aim to establish
a global network of stations for the quantitative
measurement of volcanic gas emissions.
The project is based on a newly designed scanning
mini-DOAS instrument. Primarily, the instruments
will be used to provide new parameters
in the toolbox of the observatories for risk
assessment, gas emission estimates and geophysical
research on the local scale. In addition to this,
data will be exploited for other scientific purposes,
e.g. global estimates of volcanic gas emissions and
large scale volcanic correlations. Moreover, the instruments
also allow studies of climate change and
studies of stratospheric ozone depletion. In particular,
large scale validation of satellite instruments
for observing volcanic gas emissions will be possible
for the first time, thus bringing the observation
of volcanic gas emissions from space a significant
step forward [Khokhar et al. , 2005].
Methods and results During the first year of
the project, the main emphasis was on the design
and production of a fully functional prototype of
a scanning DOAS instrument specifically suited
for the measurement of volcanic emission fluxes.
The first measurements were conducted with this
prototype at Mt Etna, Sicily, Italy, in September
2006 (see Figure 2.5). During this measurement
campaign, it was established that the proto-
type is capable of measuring both SO2 and BrO
in volcanic plumes, as well as the wind speed inside
the plume. By combining this information,
BrO/SO2 ratios and real-time SO2 fluxes can be
compiled. The instruments are designed to operate
on a stand-alone basis over long periods of
time. Therefore, a large amount of data will be
compiled, and a database for archiving this data
was designed and tested. A fully functional search
mask was conceived to allow quick access to data
of interest.
Outlook/Future work The next step is to install
a larger number of NOVAC instruments at
the respective sites. Besides the studies mentioned
above, we also plan to conduct investigations
with respect to chemical components and
processes taking place inside volcanic plumes. After
validating satellite measurements of volcanic
emissions, worldwide monitoring will be possible
and global estimates of volcanic gas emissions
(SO2, BrO, CS2) will be compiled. These will allow
us to analyze the impact of volcanic emissions
on global climate change and tropospheric chemistry.
Funding EU Project: NOVAC
Main publications www.novac-project.eu

2.1. TROPOSPHERIC RESEARCH GROUP 23
2.1.6 Enhancement and improvement of the DOAS software DOASIS;
Development of the NOVAC database
Thomas Lehmann
Abstract The existing DOASIS framework for DOAS measurements and evaluations was enhanced
by including new functions, control of new spectrometers and correction of software bugs.
The NOVAC (Network for Observation of Volcanic and Atmospheric Change) project will provide
continuous gas measurements of 15 - 25 active volcanos. For the estimated 1 billion or more spectra,
a sophisticated and high performance database is being developed.
Figure 2.6: Screenshot of the standard screen of
DOASIS. A measured spectrum can be seen in the
big window.
Background To use the Differential Optical
Absorption Spectroscopy (DOAS), an efficient
software basis is needed. The DOASIS framework
covers the whole range from hardware support,
data management to the evaluation process
[Kraus, 2005].
The huge amount of spectra an of parameters per
spectrum in the NOVAC project can only be evaluated
reasonably with a large and fast database
system. An emphasis has to be placed on the
programming of searches inside the database to
ensure that all scientists of the collaboration can
find the data that fit their needs.
Methods and results The programming of
DOASIS took place inside the Microsoft .NET
environment, using C# and JScript as programming
languages. The communication with the
spectrometers works via ActiveX controls. Several
new spectrometers (Ocean Optics’ x4000 series,
QE65000) were implemented into the framework.
By analyzing the code step by step, existing errors
have been removed and a documentation was
begun. Generally, the whole system was more
adapted to the user requirements. DOASIS is
used by various groups world-wide and new releases
are published on a regular basis.
As database system for NOVAC, a MySQL
database is used. Storing and querying the data is
Figure 2.7: Screenshot of the search page of the
NOVAC database. The input form is on top, below
the table of results.
done with the programming language PHP. The
whole system will run on a Linux-cluster.
For conducting searches in the database, various
search- and sorting-options are implemented that
are individually adjustable for the different user
groups. The database is used via webinterfaces.
Found scans and spectra can be downloaded as
a package or can be plotted directly from the
database.
A precise structure of the database and a modular
programming are important to guarantee later
changes and scalability. An emphasis has to be
placed on the performance optimization, where
satisfying results can often be found empirically
only. The search for data and the import of data
already work for the most part.
Outlook/Future work The next steps in programming
DOASIS will be primarily the verification
and adaption of the mathematical evaluation
routines, furthermore continuous changes in the
user interface.
Concerning NOVAC, the next steps will be to
configure the database in a way that it can be
easily modified to be used locally in the associated
observatories, furthermore the improvement
to high performance and the extension of the
plotting function.
Funding NOVAC

24 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.1.7 Long-Path-DOAS Measurements of VOCs and HOx precursors in
Mexico City during MCMA-2006
André Merten ( Philip Sheehy 1 , Rainer Volkamer 1,2 )
1 MIT, Cambridge, MA 02139; 2 UC San Diego, La Jolla, CA 92093
Abstract Two Long-Path-DOAS instruments were installed in Mexico City in March 2006 as part of
MCMA2006 field campaign to measure VOC and radical precursors of HOx (Glyoxal, HCHO, HONO)
and other species in a megacity urban environment.
Toluene time series from different light paths
Mexico City March 2006
200
180
160
140
120
100
80
60
40
20
0
04.03 05.03 06.03 07.03 08.03 09.03 10.03 11.03
date [UTC]
toluene light path 1 to reflector at ground
toluene light path 2 to reflector at water tower
Toulene [ppb]
Opitical density
1.0x10 -2
0.5x10 -2
0
-0.5x10 -2
-1.0x10 -2
Naphthalene fit result Mexico City 2006 DOAS#1
08.03.2006 14:32:43 UTC
274 276 278 280 282 284 286
wavelength nm
measurement (RMSE= 6,12E-4 ∆= 4,90E-3)
naphthalene (5,07E-1+/-1,0E-1)ppb
9,58E+9cm -3 CD=1,97E+15 mean OD=3,83E-3
Figure 2.8: left: time series of different light paths make toluene plume visible. right: sample spectrum
of the polyaromatic specie naphtale
Background Two Long-Path-DOAS instruments
were installed in Mexico City in March
2006 during the MCMA-2006 (Mexico City
Metropolean Area) field campaign as part of
the MILAGRO (Megacity Initiative: Local and
Global Research Observations) project which also
involves airborne measurements and field studies
in other areas of Mexcio. The goal of MILA-
GRO is to improve the knowledge of the chemistry
and transport processes in the Mexico City
atmosphere and use this as a model to describe
the conditions in other megacities and their global
impact. The measurements were performed in collaboration
with Molina Center for Energy and the
Enviroment and UCSD.
Methods and results The DOAS1 telescope
primarily measured aromatic volatile organic compounds
(VOCs) as precursors for secondary organic
aerosol (SOA) formation, among other
species like O3 and SO2. The telescope was oriented
alternately to two reflector arrays at an
altitude of 35m and at the ground. Measured
VOCs included benzene derivatives e.g. toluene,
styrene, phenol, cresols and xylenes, as well as
two ring aromatic compounds, e.g., naphthalene
(Figure 2.8 right panel) and methylnaphthalene.
Episodes of remarkably high concentrations of
toluene (e.g.190 ppb on March 8 left panel) and
styrene (14.5 ppb on March 23) were observed.
DOAS2 was dedicated mainly to measure HOx
radical precursors (Glyoxal, HONO, HCHO, O3).
The NO2 measurement shows a mean daily maximum
of 71ppb with maximal values of 133 ppb.
Glyoxal, a product of VOC oxidation, showed
maximum concentrations between 0.5 and 1.4 ppb
. For the first time during a field campaign a new
fibre optics set up was used to couple the light
source in the telescope and to receive the light
from the reflector. This set-up provides a higher
stability of the alignment and improves the spectral
characteristics of the light source. A particular
focus of the combined DOAS setup was to
assess horizontal gradients of species that were
measured by both instruments on different spatial
scales and directions. While similar values
are measured for NO2, SO2, HONO, HCHO and
O3, the concentrations of VOC differ significantly
on the two different light paths probably due to
plumes of solvents moving through the city (left
panel).
Outlook/Future work The extensive data set
combined with other measurements like meteorological
information will allow to evaluate chemical
models describing the air pollution in megacities.

2.1. TROPOSPHERIC RESEARCH GROUP 25
2.1.8 Long-Path-DOAS Measurements with new fibre optic set-up
André Merten (Jens Tschritter)
Abstract For the first time during a field campaign a new fibre optics set up was used to couple the
light source in the telescope and to receive the light from the reflector. This set-up provides a higher
stability of the alignment and improves the spectral characteristics of the light source.
Figure 2.9: schematic view of the new fibre optic set-up for DOAS devices
Background Long-Path-Telescopes are commonly
used for atmospheric trace gas measurement,
especially in combination with the DOAS
(Differential Optical Absorption Spectroscopy)
analysis technique. Such an instrument combines
the emitting and receiving telescope in one device
with a double-Newton-style set up and a Xe-high
pressure lamp as light source and has a typical size
from 1..2m. Therefore this instrument requires a
high effort in planning and executing of field measurements
and has also a limited signal-to-noise
ratio. The signal-to-noise ratio is limited due to
the inadequate characterization of the spectrum of
the light source. The used Xenon-high pressures
arc lamps are showing strong variation of spectral
structures across the arc. When using a ’shortcut
optics’ to obtain the lamp emission spectrum is
not guaranteed that the same area of the arc is
imaged used in the measurement. This can cause
strong residual structures, which can be misinterpreted
as optical densities. Another problem is
the complicated alignment of the Long-Path telescope,
since all optical elements must be adjusted
exactly to obtain good light throughput, which is
only possible at night and limits it use as an automatic
running air quality monitor. The dimensions
and the weight of the lamp house require
also a certain size and stability of the whole telescope.
A smaller and easier to handle, and more
reliable telescope would extend the range of the
application for DOAS instruments.
Methods and results Transmitting the light
of the lamp by an optical fibre placed in the focus
of the main mirror, instead of the first plane
mirror, was already tested successfully. The lamp
must not be connected mechanically with the tele-
scope anymore and the same area of the arc is imaged
in measurement and short cut regime. Since
the retroreflector is imaged again to its origin
(with a small displacement) emitting and receiving
fibres were combined together in a bundle.
Now as son as the telescope catches the reflector,
the reflected light hits also to the receiving
fibre (Figure 2.9). The system is now much easier
to align and due to the fewer degrees of freedom
much more stable. And in addition, it is also more
efficient. For the quality of the short cut system a
uniform illumination of the receiving fibre is important.
Different reflecting materials were tested
and the best results were reached with a quartz
stray disc that is placed with a small motor directly
in front of the fibre bundle. This set-up was
tested successfully with a telescope with 1,5m focal
length in the visible and near UV ranges and
then used successfully in the MCMA-2006 (Mexico
City Metropolitan Area) campaign in march
2006 measure NO2, HCHO, Glyoxal and other
species. For three weeks no manual realignment
of the telescope was necessary, except for the illumination
of the fibre by the lamp, which is not
automated yet but can be done very simple when
running the short cut optics.
Outlook/Future work The optimal fibre optic
configuration is now a topic of diploma thesis
that should lead to the complete understanding
of the optical behaviour and therefore to a new
generation of DOAS telescopes [see report from
Tschritter, 2.1.13]. The use of fibre optics offers
the possibility to work with other light sources
like LED or SLD and a fast switch between these
sources.

26 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.1.9 Tomographic LP-DOAS measurements of 2D trace gas distributions
in Heidelberg
Participating scientists Denis Poehler, Andreas Hartl, Ulrich Platt
Abstract Two dimensional distributions of trace gases were investigated with relatively high spatial
and temporal resolution by tomographic LP-DOAS technique in the city of Heidelberg. In total
nearly simultaneous measurements along 20 different light paths were performed. Using tomographic
inversion techniques first two dimensional NO2 and SO2 distributions could be achieved.
NNO N O 2
8:30 A M
9.2.2006
w in d
directio n
S O 2
8:30 A M
9.2.2006
w in d
directio n
Figure 2.10: Measurement setup and reconstructed NO2 and SO2 trace gas distributions in the city of
Heidelberg. The white lines in the map of Heidelberg indicate the measured light paths with LP-DOAS
technique. The yellow lines indicate the boxes used for the reconstruction. Center and right panel
show distributions of NO2 and SO2, respectively. Colour scale: 1 unit = 5∗10 11 Molec./cm 3 = 18.9ppb
(preliminary results).
Background LP-DOAS (Long Path-
Differential Optical Absorption Spectroscopy) is
a well known remote sensing technique for measuring
the average concentration of tropospheric
trace gases along extended light paths in the open
atmosphere. In order to retrieve information of
the spatial trace gas distribution tomographic LP-
DOAS measurements are useful. They combine
the measurement along several intersecting light
paths with tomographic inversion techniques and
allow 2 and 3 dimensional retrieval of trace gas
distributions. The development of the ”Multibeam”
LP-DOAS telescope Pundt & Mettendorf
[2005], allows the measurement along several light
paths simultaneously with one instrument. With
the suitable combination of two or more ”Multibeam”
telescopes a good coverage of the investigating
area can be achieved (see Figure 2.10).
Methods and results In a campaign in Heidelberg,
Germany, a measurement set-up encompassing
a total of 20 light paths by using three
”Multibeam” LP-DOAS instruments (placed on
the buildings: IUP, Heidelberger Druckmaschinen
and SAS) is being tested. 18 retro reflector arrays
are installed on different buildings all over
the city, and two reflectors are installed on the
mountains for further three dimensional reconstructions.
The investigated area is about 4 * 4
km 2 above the city centre and covers different ur-
ban areas with different emission sources. In the
detected wavelength range from 285nm to 365nm
the average concentrations of the trace gases NO2,
SO2, O3, HCHO and HONO along each light path
could be retrieved with a temporal resolution below
15 minutes. The first evaluated data from
winter 2005/06 show high accuracy for NO2 (Error
≈ 2%) and SO2 (Error ≈ 4%) mean concentrations.
They allow to derive two-dimensional
distributions for these trace gases above the city.
We were able to create time series of the distributions
for several days. Thus different emission
sources varying strongly in space and time can be
identified. We can localise emissions from traffic
(mainly NO2) at the high traffic roads and resident
heating systems (mainly SO2). In combination
with several weather stations transport of the
gases can be studied. The results are compared
with in-situ monitors.
Outlook/Future work The results demonstrate
that tomographic DOAS measurements can
be used to study emissions and transport of trace
gases and are valuable input to evaluate models
predicting the air quality. From improved measurements
in summer / autumn / winter 2006 we
expect to retrieve the trace distributions of additional
components. To improve the quality of the
reconstructed distributions, we intend to optimize
the reconstruction grid.

2.1. TROPOSPHERIC RESEARCH GROUP 27
2.1.10 DOAS measurements of iodine oxides in the framework of the MAP
project
Katja Seitz (Denis Pöhler, Maria Martin, Torsten Stein, Ulrich Platt)
Abstract The role of iodine oxides as precursors for formation of secondary marine aerosols (SMA)was
investigated by active as well as passive DOAS measurements which were performed in the framework
of the MAP (Marine Aerosol Production) project. During an intensive measurement campaign simultaneous
measurements of halogen oxides were performed at the Mace Head research station (Irish
West Coast) and on board the Celtic Explorer research vessel.
Figure 2.11: Ship Course of the Celtic Explorer, colour indicates biological activity.
Background Recent field and laboratory studies
indicate a great relevance of reactive iodine in
new particle formation processes. Since particles
in the marine atmosphere affect the microphysical
properties of clouds, they have a potential impact
on climate. Objective of MAP was to quantify the
key processes associated with primary (PMA) and
secondary marine aerosol production from natural
sources.
Methods and results To get seasonal information
of the correlation between biological activity
and the iodine oxides as precursor of SMA
two Mini-MAX-DOAS instruments were established
at Mace Head research station. In order
to validate the results of the Mini-MAX-DOAS
and also due to the better detection limit and the
possibility to also measure at nighttime during an
intensive campaign in June additional longpath
DOAS measurements were performed. Simultaneous
there were Mini-MAX-DOAS measurements
on board the Celtic Explorer research vessel cruising
the Northern Atlantic in front of the Irish west
coast. Objective on the Celtic Explorer was to
quantify the particle formation independent from
coastal influence. In first evaluations IO levels
up to ≈ 3.5ppt could be detected at Mace Head
with the Mini-MAX-DOAS as well as with the
longpath DOAS. Also the detection of iodine oxides
was correlated with large particle formation
events. In first evaluations no iodine oxides could
be detected for the ship cruise.
Outlook/Future work In the next step more
sophisticated evaluation of all data have to be performed.
The results will then be compared to informations
available from other groups involved in
MAP e.g. particle formation events, tidal height
and biological activity.
Funding PhD Thesis in the framework of the
MAP project, funded by the European Union.

28 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.1.11 Applicability of light-emitting diodes as light sources for active
DOAS measurements
Holger Sihler (Christoph Kern, Ulrich Platt)
Abstract The spectral stability of light-emitting diodes (LEDs) was studied in view of their applicability
in Long Path Differential Optical A bsorption Spectroscopy (LP-DOAS). Beside a constant
temperature also a highly accurate current source to drive the LEDs was found to be essential.
intensity of LED [a.u.]
10 18
10 19
10 20
10 21
400 420 440 460 480 500 520
10 22
540
wavelength [nm]
Figure 2.12: Spectral emission of a Luxeon LXHL-LR3C high power 3 W royal blue LED (at 700 mA,
10 ◦ C, blue line) in comparison with the absorption cross sections of two trace gases – NO2 (Voigt
2002, red line) and Glyoxal (Volkamer 2005, black line) – which have significant absoption structures
in this spectral range.
Background To date, high pressure xenon arc
lamps have established themselves as the most
common light sources for active DOAS instruments.
However, these have several disadvantages
including poor power efficiency in the required
wavelength region and short lifetime resulting in
high maintenance costs. Modern LEDs potentially
represent a very advantageous alternative
for both LP-DOAS [Kern et al. , 2006] and cavity
enhanced absorption spectroscopy (CEAS) [Ball
et al. , 2004; Langridge et al. , 2006]. Additionally
LEDs are much easier to maintain considering the
risk of explosions and interfering electromagnetic
radiation.
Methods and results As one may notice in
the comparison between the emission of an LED
and the trace gas absorption cross sections (Figure
2.12), the LED spectrum contains some narrowband
structures considered to be etalon structures.
Only a slight variation of these structures
during the measurement process increases
the residual of a DOAS evaluation by one order of
magnitude or even more in comparison to Xenon
arc lamps. Stabilising their emission spectrum is
therefore the key to make LEDs competitive as
DOAS light-sources.
The spectral position of the etalon structure
depends on the chip temperature. A non-zero
heat resistance between chip and heat sink yields
optical density of trace gas [cm2/molecule]
a dependency on both the heat sink tempearture
and the dissipation of electrical energy inside the
chip. In the special case of the LXHL-LR3C an
already attained temperature stabilisation within
0,1 K corresponds to 0,1 % of the current. Hence,
a stabilisation of the LED drive current was found
to be as important as controlling the temperature.
A compact sealed LED housing with a peltiercooled
heatsink and molecular sieve drying agent
was designed to decouple the LED from the ambient
temperature. Together with a standard PIDcontroller
and a current source, the spectral noise
of a LED could be reduced to a value lower than
that of halogen lamps. The stability of an arc
lamp has not been attained yet.
Funding IUP
Outlook/Future work Future experiments
will concentrate on UV-LEDs to detect further
trace gases (e.g., SO2, ClO, or CH2O). Also superluminescent
LEDs (SLEDs) will be studied in
respect to their applicability. The latter provide
very high radiances but are only in the wavelength
region above 650 nm available. Also the application
of an even more precise temperature controller
(TEC) is very promising. A newly customdesigned
current source-TEC combination has to
be tested and compared to industry standard components.

2.1. TROPOSPHERIC RESEARCH GROUP 29
2.1.12 Multi Axis Differential Optical Absorption Spectroscopy (MAX-
DOAS) of Trace Gas and Aerosol Distributions
Roman Sinreich (Rainer Volkamer, Thomas Wagner)
Abstract MAX-DOAS measurements, i.e. DOAS measurements at different elevation angles from
the ground, enable the detection of trace gases in the planetary boundary layer even at low concentrations
due to their long light path at low elevation angles. Furthermore, MAX-DOAS values combined
with radiative transfer modelling can yield distributions of trace gases and aerosols.
Figure 2.13: HONO SCDs on March 6th, 2006, in Mexico City. Enhanced values in the morning were
typical throughout the measurement campaign.
Background For three decades DOAS has been
applied to measure trace gases like e.g. NO2, SO2
or HCHO by means of sunlight [?]. Sunlight passing
through the atmosphere is scattered and absorbed
by gas molecules in the air whereby the
absorption occurs at wavelengths which are characteristic
for each trace gas. This absorption pattern
is suitable to detect and quantify the according
trace gases.
In this study, ground-based DOAS measurements
were performed and their spectra analysed.
By using the measured results and modelled data
from a radiative transfer model, it is possible to
derive trace gas and aerosol distributions.
Methods and results The retrieval of trace
gases by means of DOAS yields Slant Column
Densities (SCDs) which depend on the concentration
of the according trace gas and the light
path of the measurement. Since scattered sunlight
is measured, the light path is not readily defined
and has to be calculated by atmospheric radiation
transport models. Furthermore, different elevation
angles from the ground have to be performed
in order to get information on the vertical profile.
This method is called Multi-Axis-DOAS (MAX-
DOAS) and allows to derive gas and aerosol distributions
near the surface.
Aerosol properties can be derived indirectly by
measurements of gas species whose 3-dimensional
distribution is already known and relatively constant.
E.g. O4, whose concentration is proportional
to the square of the O2 concentration, provides
these qualities. So variations in measured
O4-SCDs are dominated by the aerosol distribution,
which causes different light paths in the atmosphere
[Wagner et al. , 2004].
In March 2006, MAX-DOAS measurements
were performed at several sites in Mexico City in
the framework of MILAGRO (Megacity Initiative:
Local and Global Research Observations, see also
report of Merten et al. 2.1.7 ). Thereby, SCDs
of NO2, CHOCHO, HCHO, O4 and SO2 could be
retrieved. Furthermore, SCDs of HONO at daytime
could be detected for the first time by means
of MAX-DOAS (a typical diurnal cycle of HONO
SCDs is shown in Figure 2.13).
Outlook/Future work The MAX-DOAS values
from Mexico City will be compared with insitu,
active DOAS and satellite measurements.
Moreover, improvements of the technique of deriving
gas and aerosol distributions will allow to
perform the inversion procedure more analytically.
Main publication Sinreich et al. [2006]

30 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.1.13 Third Generation DOAS Telescopes
Jens Tschritter (Andre Merten, Ulrich Platt)
Abstract To get high resolution trace gases measurements in the troposphere, A. Perner and U.
Platt developed an active DOAS System in 1980. Technical improvements in fiber optics now make a
redesign of the classic Active Long-Path system possible in order to use smaller telescopes with easier
handling yet maintaining the same optical properties and light throughput.
A: Axelssons telescope
projected mirror surface
transmittsurface
Receive surface
receive surface
spectrograph
light source
retro
B: 3rd Generation telescope
receive fiber
projected mirror surface
for transmission and receive
transmission fiber
spectr. spectrograph
light source
Figure 2.14: Lightpath of Axelssons System (left) and the Third Generation Telescope (right)
Background Optical Absorption Spectroscopy
is a well known laboratorial analyzing instrument.
Specially for trace gas measurements in the troposphere
the Differential Optical Absorption Spectroscopy
(DOAS) is well established. The classic
experimental set up of a active DOAS system consisting
of a transmitting telescope, which sends
a light beam trough the atmosphere, a retro reflector,
a receiving telescope, a controlling system
and a spectrometer. The telescopes main mirror
is used as transmitting mirror as well as receiving
mirror. This coaxial merge of a transmitting and
receiving telescope as shown in the Fig. 2.14 A
was first described by Axelsson et al. [1990]. The
difficult handling and the size, led to a decrease in
the number of measurements with Axelsson-type
long path systems in the last years. Therefore
passive systems, which are using the sun as light
source, are used more and more for tropospheric
trace gas measurements. However, the active systems
allow measurements at night and with spectral
ranges different from the sunlight. Thus we
decided to develop a smaller long path telescope
with easier handling.
Methods and results Using fibers to conduct
light in the telescope allows to use a defusor plate
as short cut system instead of a retro reflector
to reduce lamp structures and to provide uniform
illumination of the spectrographs field of view,
Abstract
which reduces the measurements residuum. Because
we use no mirrors to conduct the light on
our telescopes main mirror we have no shadows,
so we can use the complete main mirror for sending
and receiving and we gain more light intensity
in the spectrograph. Motors controlled by the
measurement program automatically optimize focus
and direction of our light beam and help to
adjust the optical set up. we experimentally verified
that the intensity coupled into the fiber at
the receiving end should not depend on the focal
length of our telescopes main mirror. This result
of our test-measurements is the base fact for constructing
a smaller telescope with the same light
throughput.
Outlook/Future work If we adapt the f/# of
our spectrometer to that of our telescope we would
be able to construct a very small telescope. This
Third Generation Telescope (fig. 2.14 B) which
can be carried by one person allows measurements
in remote areas. New software applications help
handling the optical set up. Using light emitting
diodes (LED) as light source could help to further
reduce the costs. Thus, we can build a global
measurement network for trace gases in the troposphere
which helps us to understand the atmospheric
chemistry.
retro

2.1. TROPOSPHERIC RESEARCH GROUP 31
2.1.14 Testing a new Near-IR Sensor for Detection of Methane
Markus Woyde , Christian Frankenberg, Thomas Wagner, Ulrich Platt
Abstract A new spectrometer with InGaAs linear image sensor was tested with respect to its
applicability for detecting methane in the near infrared region. Measurements of CH4 cuvettes were
conducted to test its feasibility as well as atmospheric observations using a hill as reflective surface
for sunlight providing a new observation mode.
log(I/I 0 )
expected transmission
−0.1
−0.15
−0.2
−0.25
−0.3
1635 1640 1645
wavelength [nm]
1650 1655 1660
1
0.8
0.6
0.4
0.2
fitted
measured
Unconvolved expected transmission
0
1635 1640 1645
wavelength [nm]
1650 1655 1660
Figure 2.15: top panel: Displayed is the optical density of a cuvette filled with methane; measured
data is shown in green, IMAP-DOAS fit in blue. bottom: Unconvolved expected transmision resolved
in a wavelength-grid corresponding to pixels on the sensor.
Background Methane is, after carbon dioxide,
the second most important anthropogenic
greenhouse gas, contributing directly 0.48 Wm −2
to the total anthropogenic radiative forcing of
2.43 Wm −2 by well-mixed greenhouse gases
(IPCC, 2001). Its individual source strengths
need to be quantified more precisely. There have
already been successful satellite-based CH4 measurements
by SCIAMACHY onboard ENVISAT
using the DOAS-technique providing a global coverage
but with a limited temporal and spatial resolution.
Therefore it is desirable to compensate
for these limitations by developing a ground-based
instrument.
Funding IUP
Methods and results The sensor properties
such as dark current, offset and linearity were
characterized. After that measurements of CH4
cuvettes were performed, covering a spectral
range from about 1600nm to 1670nm (see figure
2.15).The concentration was analyzed by means of
IMAP-DOAS developed by C. Frankenberg. As
one can see there is already a good agreement between
data and fit. For better results a more detailed
investigation of the slit-function is nescessary.
Further, the sensor was tested in Heidelberg
using a new observation mode. A hill at about
2.1km was used as reflective area for sunlight,
the reference spectrum was obtained by observing
sunlight directly reflected into the spectrograph
by an aluminium plate, so that it is possible to
determine the CH4 concentration along the way
between spectrograph and hill.
Outlook/Future work Future work will encompass
improving the instrument by a better
temperature stabilization and preparing it for field
campaigns. This would enable us to examine the
differences between modeled data and measured
data by SCIAMACHY. Furthermore an interesting
application might be searching for leakages in
gas pipelines or measuring water vapor in the atmosphere.
Main publications ?

32 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
References
Allen, G., Mather, T.A., McGonigle, A.J.S., Aiuppa, A., Delmelle, P., Davison, B., Bobrowski,
N., Oppenheimer, C., Pyle, D.M., & Inguaggiato, S. 2006. Sources, size distribution and downwind
grounding of aerosols from Mt. Etna. Journal of Geophysical Research, 111(D10302).
doi:10.1029/2005JD006015.
Axelsson, H., Galle, B., Gustavson, K., P., Regnason, & Rudin, M. 1990. A transmitting/receiving
telescope for DOAS-measurements using reflector technique. Pages 641–644 of: Series, OSA Technical
Digest (ed), Digest of Tropical Meeting on Optical Remote Sensing of the Atmosphere, vol. 4.
Optical Society of America.
Ball, S. M., Langridge, J. M., & Jones, R. L. 2004. Broadband cavity enhanced absorptions spectroscopy
using light-emitting diodes. Chem. Phys. Lett., 398, 68–74.
Barkly, M.P., Frieß, U., & Monks, P.S. 2006. Measuring atmospheric CO2 from space using Full
Spectral Initiation (FSI) WFM-DOAS. Atmospheric Chemistry and Physics Discussion, 6, 2765–
2807.
Barrie, L. A., & Platt, U. 1997. Arctic tropospheric chemistry. Overview to Tellus special issue, 49B,
450–454.
Bobrowski, N., & Platt, U. 2006. Bromine Monoxide Studies in Volcanic Plumes. Journal of Volcanology
and Geothermal Research. submitted 31. 7. 2005.
Bobrowski, N., Hönninger, G., Lohberger, F., & Platt, U. 2006a. I-DOAS: A new monitoring technique
to study the 2D distribution of volcanic gas emissions. Journal of Volcanology and Geothermal
Research, 150(4), 329–338.
Bobrowski, N., Burton, M.R., Caltabiano, T., Salerno, G., & Platt, U. 2006b. Measurements of
the Halogen and SO2 Flux from Mt. Etna in September 2003. Geophysical Research Letters. in
preparation.
Bobrowski, N., Glasow, R.v., Aiuppa, A., Inguaggiato, S., Louban, I., Ibrahim, O.W., & Platt,
U. 2006c. Reactive Halogen Chemistry in Volcanic Plumes. Journal of Geophysical Research.
accepted,2006JD007206.
Bossmeyee, Jens. 2006. Studies of Aldehydes in an Atmosphere Simulation Chamber, Degradation of
Higher Aldehydes by Nitrate Radicals. PhD Thesis, Universität Heidelberg.
Bruns, M., Buehler, S.A., Burrows, J.P., Richter, A., Rozanov, A., Wang, P., Heue, K.-P., Platt, U.,
Pundt, I., & Wagner, T. 2006. NO2 Profile retrieval using airborne multi axis UV-visible skylight
absorption measurements over central Europe. Atmospheric Chemistry and Physics, 6, 3049–3058.
Burkholder, J. B., Curtius, J., Ravishankara, A. R., & Lovejoy, E. R. 2004. Laboratory studies of the
homogeneous nucleation of iodine oxides. Atmos. Chem. Phys., 4, 19–34.
Cauer, H. 2004. Schwankungen der Jodmenge der Luft in Mitteleuropa, deren Ursachen und deren
Bedeutung für den Jodgehalt unserer Nahrung (Auszug). Angewandte Chemie 52, 11, 625–628.
Cox, R. A., Bloss, W. J., Jones, R. L., & Rowley, D. M. 1999. OIO and the Atmospheric Cycle of
Iodine. Geophys. Res. Lett., 26 (13), 1857–1860.
Frieler, K., Rex, M., Salawitch, R.J., Canty, T., Streibel, M., Stimpfle, R.M., Pfeilsticker, K., Dorf,
M., Weisenstein, D.K.and Godin-Beekmann, S., & von der Gathen, P. 2006. Towards a better quantitative
understanding of polar stratospheric ozone loss. Geophysical Research Letters. submitted.
Frieß, U., & Platt, U. 2006a. Absolute concentration measurements by DOAS at ”Zero Visibility”. in
preparation.
Frieß, U., & Platt, U. 2006b. Tropospheric IO in the Antarctic Coastal Region - Observations by
Multi-Axis DOAS. in preparation.
Frieß, U., Monks, P.S., Remedios, J.J., Rozanov, A., Sinreich, R., Wagner, T., & Platt, U. 2006.
MAX-DOAS O4 measurements: A new technique to derive information on atmospheric aerosols.
(II) Modelling studies. Journal of Geophysical Research, 111(D14203). doi:10.1029/2005JD006618.

2.1. TROPOSPHERIC RESEARCH GROUP 33
Frins, E., Bobrowski, N., Platt, U., & Wagner, T. 2006. Tomographic multiaxis-differential optical
absorption spectroscopy observations of Sun-illuminated targets: a technique providing well-defined
absorption paths in the boundary layer. Applied Optics, 45(24), 6227–6240.
Hak, Claudia. 2006. VARIABILITT VON FORMALDEHYD-KONZENTRATIONEN IN DER VER-
SCHMUTZTEN PLANETAREN GRENZSCHICHT: MESSUNGEN IM BALLUNGSRAUM VON
MILANO. PhD Thesis, Universität Karlsruhe.
Hartl, A., Song, B.C., & Pundt, I. 2006. 2-D reconstruction of atmospheric concentration peaks from
horizontal long path DOAS tomographic measurements: parametrisation and geometry within a
discrete approach. Atmospheric Chemistry and Physics, 6, 847–861.
Hoffmann, T., O’Dowd, C. D., & Seinfeld, J. H. 2001. IO homogeneous nucleation. An explanation
for coastal new particle formation. Geophys. Res. Lett., 28 (10), 1949–1952.
Kern, C., Trick, S., Rippel, B., & Platt, U. 2006. Applicability of light-emitting diodes as light sources
for active DOAS measurements. Applied Optics, 45, 2077–2088.
Khokhar, M. F., Frankenberg, C., Van Roozendael, M., Beirle, S., Kühl, S., Richter, A., Platt, U., &
Wagner, T. 2005. Satellite Observations of Atmospheric SO2 from Volcanic Eruptions during the
Time-Period of 1996 to 2002. Adv. Space Res., 36(5), 879–887.
Kraus, Stefan. G. 2005. DOASIS - A Framework Design for DOAS. PhD Thesis, Universität
Mannheim, Universität Heidelberg.
Langridge, J. M., Ball, S. M., & Jones, R. L. 2006. A compact broadband cavity enhanced absorption
spectrometer for detection of atmospheric NO2 using light emitting diodes. Analyst, 131, 916–922.
Leck, C., & Bigg, E. K. 1999. Aerosol production over remote marine areas - A new route. Geophys.
Res. Lett., 26, 3577–3580.
Lee, J. S., Kim, Y. J., Geyer, A., & Platt, U. 2006. Simultaneous Measurements of Atmospheric Trace
Gases and Atmospheric Visibility by DOAS System. in preparation.
Leigh, R. J., Corlett, G. K., Frieß, U., & Monks, P. S. 2006. concurrent multi axie differential optical
absorption spectroscopy system for the measurement of tropospheric nitrogen dioxide. Applied
Optics, 45(28), 7504–7518.
Lindberg, S., Brooks, S., Lin, C. J., Scott, K. J., Landis, M. S., Stevens, R. K., Goodsite, M., &
Richter, A. 2002. Dynamic Oxidation of Gaseous Mercury in the Arctic Troposphere at Polar
Sunrise. Environ. Sci. Technol., 36, 1245–1256.
Lohberger, F., Hönninger, G., & Platt, U. 2004. Ground-based imaging differential optical absorption
spectroscopy of atmospheric gases. Applied Optics, 43(24), 4711–4717.
Louban, I, Bobrowski, N., Rouwet, D., Inguaggiato, S., & Platt, U. 2006. Imaging DOAS for Volcanological
Applications. in preparation.
Mettendorf, K.U., Hartl, A., & Pundt, I. 2006. An Indoor Test Campaign of the Tomography Long
Path Differential Optical Absorption Spectroscopy (DOAS) Technique. Journal of Environmental
Monitoring, 8, 279–287.
O’Dowd, C., Jimenez, J. L., Bahreini, R., Flagan, R. C., Seinfeld, J. H., Hämeri, K., Pirjola, L., ans
S. G. Jennings, M. Kulmala, & Hoffmann, T. 2002. Marine aerosol formation from biogenic iodine
emissions. Nature, 417, 632–636.
Oppenheimer, C., Tsanev, V. I., Braban, C. F., Cox, R. A., Adams, J. W., Aiuppa, A., Bobrowski, N.,
Delmelle, P., Barclay, J., & McGonigle, A. J. 2006. BrO formation in volcanic plumes. Geochimica
et Cosmochimica Acta, 70, 2935–2941.
Platt, U. 1994. Differential optical absorption spectroscopy (DOAS). In: Sigrist, M. W. (ed), Air
Monitoring by Spectroscopic Techniques. New York: John Wiley.
Platt, U., & Hönninger, G. 2003. The Role of Halogen Species in the Troposphere. Chemosphere 52,
2, 325–338.

34 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Platt, U., & Janssen, C. 1996. Observation and role of the free radicals NO3, ClO, BrO and IO in the
Troposphere. Faraday Discuss., 100, 175–198.
Platt, U., Allan, W., & Lowe, D. 2004. Hemispheric Average Cl Atom Concentration from 13 C/ 12 C
Ratios in Atmospheric Methane. Atmos. Chem. Phys., 4, 2393–2399.
Platt, U., Pfeilsticker, K., & Vollmer, M. 2006. Chapter 24: Atmospheric Optics. In: Träger, F. (ed),
Springer Handbook of Lasers and Optics. Heidelberg: Springer.
Pundt, I., & Mettendorf, K. U. 2005. Multibeam long-path differential optical absorption spectroscopy
instrument: a device for simultaneous measurements along multiple light paths. Applied Optics,
44(23). 4985 - 4994.
Roscoe, H.K., Kreher, K., & Friess, U. 2001. Ozone loss episodes in the free Antarctic troposphere,
suggesting a possible climate feedback. Geophys. Res. Lett., 28, 2911–2914.
Sebastian, O., Geyer, A., Hönninger, G., Platt, U., Sciare, J., & Mihalopoulos, N. 2006. The influence
of radicals on DMS oxidation in the Eastern Mediterranean marine boundary layer. in preparation.
Simpson, W.R., Carlson, D., Hönninger, G., Douglas, T.A., Sturm, M., Perovich, D., & Platt, U.
2006. First-year sea-ice contact predicts bromine monoxide (BrO) levels better than potential frost
flower contact. Atmospheric Chemistry and Physics Discussion, 6, 1105111066.
Sinreich, R., Volkamer, R., Filsinger, F., Frieß, U., Kern, C., Platt, U., Sebastián, O., & Wagner, T.
2006. MAX-DOAS detection of glyoxal during ICARTT 2004. Atmospheric Chemistry and Physics
Discussion, 6, 9459–9481.
Stein, Thorsten. 2006. Diplomarbeit, Universität Heidelberg.
Stutz, J., Hebestreit, K., Alicke, B., & Platt, U. 1999. Chemistry of halogen oxides in the troposphere:
comparison of model calculations with recent field data. J. Atmos. Chem., 34, 65–85.
Stutz, J., Hebestreit, K., Hönninger, G., & U., Platt. 2006. Simultaneous measurement of iodine oxide
and nitrogen dioxide at Mace Head, Ireland. in preparation.
von Glasow, R., & Crutzen, P.J. 2004. Model study of multiphase DMS oxidation with a focus on
halogens. Atmos. Chem. Phys., 4, 589–608.
von Glasow, R., von Kuhlmann, R., Lawrence, M. G., Platt, U., & Crutzen, P.J. 2004. Impact of
reactive bromine chemistry in the troposphere. Atmos. Chem. Phys., 4, 2481 – 2497.
Wagner, T., Dix, B., v. Friedeburg, C., Frieß, U., Sanghavi, S., Sinreich, R., & Platt, U. 2004.
MAX-DOAS O4 measurements: A new technique to derive information on atmospheric aerosols -
Principles and information content. Journal of Geophysical Research, 109, D22205.
Wang, P., Richter, A., Bruns, M., Burrows, J.P., Scheele, R., Junkermann, W., Heue, K.-P., Wagner,
T., Platt, U., & Pundt, I. 2006. Airborne multi-axis DOAS measurements of tropospheric SO2
plumes in the Po-valley, Italy. Atmospheric Chemistry and Physics, 6, 329–338.
Wennberg, P.O., Hanisco, T. F., Jaegle, L., Jacob, D. J., Hintsa, E. J., Lanzendorf, E. J., Anderson,
J.G., Gao, R. S., Keim, E. R., Donnelly, S. G., Negro, L. A. Del, Fahey, D. W., McKeen, S. A.,
Salawitch, R. J., Webster, C. R., May, R. D., Herman, R. L., Proffitt, M. H., Margitan, J. J., Atlas,
E. L., Schauffler, S. M., Flocke, F., McElroy, C. T., & Bui, T. P. 1998. Hydrogen radicals, nitrogen
radicals, and the production of O3 in the upper troposphere. Science, 279, 49–53.
Xie, P., Geyer, A., Volkamer, R., Yu, Y., Platt, U., Galle, B., & Chen, L. 2006. Investigation of the
distribution of aromatic hydrocarbons in Shanghai (China). in preparation.

2.2. STRATOSPHERIC RESEARCH GROUP 35
2.2 Stratospheric Research Group
Klaus Pfeilsticker
Group members
Prof. Dr. K. Pfeilsticker, Head of group
Dr. A. Butz, Post Doc
Dr. M. Dorf, Post Doc
S. Kreycy, Diploma Student
Dipl. Phys. L. Kritten, PhD Student
M. Sc. C. Prados, PhD Student
B. Simmes, Diploma Student
Dr. F. Weidner, left by May 2006
Abstract
Our stratospheric research concentrates on an improved understanding of the photochemical processes
controlling upper tropospheric and lower stratospheric (UT/LS) ozone and its link to climate. This
overall objective is achieved by (a) high-precision spectroscopic measurements of trace gases (O3, NO2,
BrO, OClO, IO, OIO, . . . ) important for UT/LS ozone, and (b) by comparing of the obtained results
with outputs of global 3-dimensional chemistry transport models (CTM). Further, the measurements
are used to infer the spectral solar irradiance and the limb radiance of the sky in the UV/Vis spectral
range. The various studies are performed by spectroscopic techniques employed on aircrafts (Falcon,
HALO) and high-altitude balloons (LPMA/DOAS, LPMA/IASI, MIPAS-B) during international field
campaigns.
Tangent height / km
30
25
20
15
10
0.1 ppt
Retrieved IO SCD
1x and 2x IO detection limit
Modeled IO SCD assuming multiples of 0.1 ppt I y
Same as but omitting OIO photolysis
Tropopause altitude
0 2 4 6 8
IO SCD / (10 13 molecules cm -2 )
IO
Retrieved OIO SCD
1x OIO detection limit
Modeled OIO SCD assuming multiples of 0.1 ppt I y
Same as but omitting OIO photolysis
Tropopause altitude
OIO SCD / (10 13 molecules cm -2 -1 0 1 2 3
)
Figure 2.16: IO (left panel) and OIO (right panel) SCDs as a function of tangent height. Measured
data are shown as black open boxes with error bars. The theoretical detection limits inferred from
the observations are plotted as thick red lines. For IO, additionally twice the detection limit is
shown. IO SCDs exceed the detection limit below 20 km. The observations are to be compared to
modeled IO and OIO SCDs assuming different amounts of total gaseous inorganic iodine (Iy). Iodine
loadings are chosen in multiples of 0.1 ppt. Modeled SCDs are shown for two scenarios: One allows
for OIO photolysis (gray solid lines), the other scenario omits OIO photolysis (gray dotted lines). In
the range of the UT/LS (14 - 19 km), IO observations/upper limits are roughly consistent with the
model run assuming 0.3 ppt and 0.4 ppt Iy if OIO photolysis is considered and omitted, respectively.
The detection limits for OIO are consistent with more than 1 ppt and 0.3 - 0.4 ppt Iy considering and
omitting OIO photolysis, respectively.
OIO
30
25
20
15
10
Tangent height / km

36 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Scientific objectives
• Photochemistry and budget of upper tropospheric and stratospheric bromine (BrO, Bry) and
its relevance to stratospheric ozone
• Photochemistry and budget of upper tropospheric and stratospheric iodine (IO, OIO, Iy) [Butz,
2006; Schwärzle, 2005; Figure 2.16]
• Stratospheric chemistry and budget of odd nitrogen (NO, NO2, HNO3, ClONO2) [Butz, 2006];
• Partitioning and photochemistry of chlorine and bromine in the high-latitude stratosphere and
the assessment of the instantaneous in-situ ozone loss rate [Butz et al. , 2006b]
• Prominent natural and anthropogenic sources contributing to the trace gas composition of the
tropical tropopause and lowermost stratosphere (TTL/LMS) [Reichl, 2005; Schwärzle, 2005]
• Temporal and spatial dependencies of stratospheric radical concentrations (e. g. NO2/N2O5 and
BrO/OClO) [Section 2.2.5]
• Validation of remote sensing satellite instruments such as ILAS/ADEOS, POAM II and III,
SAGE II and III, ODIN/OSIRIS, GOME/ERS-2, and SCIAMACHY/ENVISAT [Butz et al. ,
2006a; Dorf et al. , 2006a]
Background
In recent years it became clear that the destructive influence on the stratospheric ozone layer needs
further investigation and monitoring. It is triggered by a changing atmospheric composition due to
the anthropogenic emission of a variety of ozone harmful and greenhouse gases. In addition, research
(to which our research group is also largely contributing) is indicating that naturally emitted and
mostly short-lived halogen bearing organic species may significantly contribute to the burden of ozone
harmful halogens (Cl, Br, and I). Most important, and evident, appears their efficient transport from
the various terrestrial and oceanic sources through the tropical troposphere into the lower stratosphere
of the tropics. It appears worthwhile to identify the various sources of these organic gases, their fate,
and their inorganic products in the tropical atmosphere. This approach is presently followed with
various experimental and theoretical methods used by the research group and the various cooperating
partners. Further, processes leading to stratospheric ozone loss, e. g. in the polar region in winter or
the decline in mid-latitude ozone, need to be investigated.
A second objective of our research relies on the experimental skills of the research group and the
known deficits in properly understanding the spectral solar irradiance and its variability. Improving
the knowledge of the latter is most important in particular for the UV-A and B spectral ranges. This
supports a better understanding of possible sun-climate interactions, the atmospheric photochemistry
and energy budget, and is of interest for the solar cell industry.
Main methods
The research objectives imply to probe the stratosphere by high-altitude (∼ 40 km) balloon soundings.
For that purpose the research group is operating (1) a self-made two channel UV/Vis spectrometer for
direct sun measurements, and (2) a novel limb-scanning UV/Vis spectrometer. Both spectrometers
are deployed on the joint French-German LPMA/DOAS (Laboratoire de Physique Moléculaire et
Applications/Differential Optical Absorption Spectroscopy) balloon payload. Jointly with our direct
sun measurements, our French partner operates a near-IR Fourier-Transform spectrometer to measure
mid-IR absorbing gases. Balloon flights are regularly performed at high (Kiruna, Sweden), mid (Aire
sur l’Adour, France), and low latitudes (Teresina, Brazil). Interpretation of the measurements also
involves radiative transfer studies and 1-D photochemical modelling on air-mass trajectories provided
by our partner Meteorologisches Institut, FU-Berlin, Germany. The model’s required initialization
is provided through outputs from a 3-D chemistry model (CTM-SLIMCAT) run by the Institute for
Atmospheric Science – School of Earth and Environment, University of Leeds, UK.
Our scientific objectives are primarily achieved through measurements of stratospheric radicals (O3,
NO2, BrO, OClO, IO, OIO, . . . ) and related trace gases (CH4, N2O, HCl, NO, HNO3, ClONO2, . . . )
and the interpretation of the results with respect to the photochemistry of stratospheric ozone. Major
research objectives involve studies of the processes leading to the formation of the ozone hole during
polar winter, the global decline in stratospheric ozone, and since recently the photochemistry and
transport in the tropical tropopause layer (TTL) and lowermost stratosphere (LMS). The research of
the group is largely contributing to various international assessments on stratospheric ozone (WMO
report in 1998, 2002, and 2006), organized by the World Meteorological Organisation (WMO).

2.2. STRATOSPHERIC RESEARCH GROUP 37
Main activities
• The retrieval and interpretation of data from past field campaigns
• Dissemination of the results obtained from previous atmospheric soundings
• Performance of a mini-DOAS flight on the MIPAS-B payload at Kiruna (67.9 ◦ N, 21.1 ◦ E) on
March 1, 2006
• The design and set-up of a novel mini-DOAS instrument for aircraft applications
Funding
Funding comes through research contracts with European Community (EU-EVK2-CT-2000-00059 and
505390-GOCT-CT-2004), the Bundesministerium für Bildung und Forschungs (BMBF) through the
DLR (DLR-50FE0017) and the Deutsche Forschungsgemeinschaft (DFG PF384/3-1 and PF384/5-1).
Cooperation within the institute and with groups outside the institute
The research group closely cooperates with the following institutions as, for example, documented in
joint peer-reviewed publications:
1. Forschungszentrum Jülich GmbH, Institut für Chemie und Dynamik der Geosphäre (ICG-I:
Stratosphäre), Jülich, Germany
2. Laboratoire de Physique Moléculaire pour l’Atmosphere et l’Astrophysique (LPMAA), Université
Pierre et Marie Curie, Paris, France
3. Harvard-Smithsonian Center for Astrophysics, Cambridge, USA
4. Institute for Atmospheric Science – School of Earth and Environment, University of Leeds,
Leeds, UK
5. Meteorologisches Institut, Freie Universität Berlin, Berlin, Germany
6. Service d’Aeronomie du CNRS, Verrieres le Buisson, France
7. Belgian Institute for Space Aeronomy (BIRA-IASB), Brussels, Belgium
8. Jet Propulsion Laboratory (JPL), Pasadena, USA
9. Institut für Atmosphäre und Umwelt, J. W. Goethe Universität Frankfurt, Frankfurt, Germany
10. European Space Agency (ESA), Nordwijk, Netherland
11. Institut für Umweltphysik und Fernerkundung, University of Bremen, Bremen, Germany
12. Chemistry Department, University of Cambridge, Cambdrige, UK
13. Institut für Meteorologie und Klima (IMK), Forschungszentrum Karlsruhe, Karlsruhe, Germany
Future work
Future work will concentrate on (1) time-resolved measurements of stratospheric radicals, (2) the budget
and trend of stratospheric bromine and iodine, (3) the photochemistry and transport of the tropical
upper troposphere and stratosphere, (4) improved measurements of the spectral solar irradiance with
an emphasis on the UV-A and B, and (5) the validation of existing (ENVISAT/SCIAMCHY) and
future satellite instruments (Metop/GOME-2 and IASI).
Peer Reviewed Publications
1. Butz et al. [2006a]
2. Dorf et al. [2006a]
3. Dorf et al. [2006b]
4. Feng et al. [2006]
5. Frieler et al. [2006]
6. Sioris et al. [2006]
7. WMO [2006]

38 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Other Publications
1. Butz et al. [2006b]
PhD Theses
1. Butz [2006]

2.2. STRATOSPHERIC RESEARCH GROUP 39
2.2.1 Observational constraints on stratospheric ozone loss cycles
André Butz (Marcel Dorf, Sebastian Kreycy, Lena Kritten, Cristina Prados, Benjamin Simmes,
Frank Weidner, Klaus Pfeilsticker)
Abstract Balloon-borne observations of a comprehensive set of trace gases in the Arctic winter
stratosphere are used to constrain a photochemical model. Model-measurement comparisons aim
at testing the consistency of various recently suggested scenarios of the involved reaction kinetics.
Particular focus is put on the ClO-BrO and the ClO-ClO cycles, and on inferring implications for
ozone loss.
Figure 2.17: Measured (boxes) and modeled (lines) slant column densities (SCD) of OClO as a function
of tangent height. Various model runs are shown as indicated in the legend.
Background Several studies indicate that measured
ozone loss in the Arctic winter/spring
stratosphere is underestimated by current stratospheric
chemistry models when using standard
recommendations for the reaction kinetics. Erroneous
representation of the known catalytic ozone
loss cycles in the models could explain why modeled
ozone loss falls short when compared to observations.
Here, recently suggested updates of
the kinetics of the two most important cycles, the
ClO-ClO and ClO-BrO cycle, are tested for consistency
with the observations.
Methods and results We discuss a case study
of the Arctic stratosphere in February 1999 where
ozone loss occurred locally in a moderately activated
polar vortex. Simultaneous balloon-borne
solar occultation observations of HNO3, NO2, NO,
HCl, ClONO2, Cly, OClO, and BrO provide a
comprehensive view of the chemical species involved
in catalytic ozone loss. In particular, simultaneous
measurements of BrO and OClO can
be used to inspect the ClO + BrO reaction, the
branching ratio of which has been questioned recently.
Simultaneous observations of ClONO2 and
NO2 are particularly useful to investigate deactivation
of the short-lived chlorine species and
the speculative existence of unstable isomers of
ClONO2. A stratospheric chemistry model is constrained
to all observed species except for OClO.
Several recently suggested updates of the relevant
reaction kinetics are tested. Model-measurement
comparisons of OClO provide an estimate on how
well the ClO-BrO cycle and the ClO-ClO cycle
are represented by the proposed model scenarios.
Implications are discussed on the basis of the modeled
ozone loss rates.
The model-measurement comparisons show that
formation of an unstable isomer of ClONO2 cannot
be reconciled with our observations. Further
suggestions concerning the photolysis rate of the
ClO dimer, the equilibrium constant between the
ClO dimer and monomer, the rate of the ClO-
ClO association reaction, and the branching ratio
of the ClO-BrO reaction produce model output
consistent with observations of OClO. However,
ozone loss can be enhanced by 10%- 20% compared
to currently recommended kinetics.
Outlook/Future work Similar studies conducted
during night-time will allow us to further
discriminate between the various suggested
kinetic scenarios. Time-resolved observations of
the build-up of OClO during sunset could further
constrain the kinetics of the ClO-BrO cycle.
Funding The present work has been supported
by ESA, BMBF, DLR and the European Union.
Main publication Butz et al. [2006b]

40 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.2.2 Is there inorganic gaseous iodine in the tropical UT/LS ?
André Butz (Marcel Dorf, Sebastian Kreycy, Lena Kritten, Cristina Prados, Benjamin Simmes,
Frank Weidner, Klaus Pfeilsticker)
Abstract Solar absorption spectra recorded during a tropical balloon flight by the LPMA/DOAS
payload are analyzed for the absorption of IO and OIO yielding undetectable or very low amounts of iodine
in the tropical UT/LS. Photochemical modeling of the partitioning among the iodine family shows
that tropical inorganic gaseous iodine (Iy) < (0.3/0.4 ± 0.1) ppt (OIO photolysis considered/omitted).
Figure 2.18: Absorption of IO in solar absorption spectra at high (upper panel) and low latitudes
(lower panels). Black line inferred IO absorption + residual. Red line inferred IO absorption. Blue
line theoretical IO absorption corresponding to 0.5 ppt below 20 km. TH tangent height.
Background Solomon et al. [1994] suggested
that already very small amounts of iodine could
significantly contribute to lower stratospheric
ozone loss. So far, most studies assessing the
stratospheric iodine budget conclude on undetectable
low amounts of gaseous inorganic iodine
(Iy). Bösch et al. [2003] gives the currently
best upper limits of Iy for high and mid-latitudes.
Here, the latter study is extended to low-latitudes
which are of particular importance due to their
crucial role in transporting tropospheric air to the
stratosphere.
Methods and results In June 2005, the
LPMA/DOAS balloon payload has been deployed
at a tropical site in northern Brazil for the first
time. While floating in the middle stratosphere,
the balloon-borne instruments recorded solar absorption
spectra during sunset. Light paths in the
upper troposphere/lower stratosphere (UT/LS)
extended over several hundred kilometers making
the observations very sensitive to minor abundant
trace species. The spectra are analyzed for
the absorption of IO and OIO in the visible spectral
range applying the DOAS retrieval algorithm.
Most importantly, the spectral retrieval of IO requires
a correction for the solar center-to-limb-
darkening effect explored in detail by Bösch et al.
[2003].
The inferred absorption of IO slightly exceeds the
theoretical, statistical detection limit but cannot
be considered trustworthy since systematic residual
structures hinder the retrieval. The OIO
retrievals yield absorptions below the detection
limit. Below 20 km altitude, upper limits for
IO and OIO consistent with the observations
range between 0.15 ppt and 0.24 ppt and between
0.01 ppt and 0.1 ppt, respectively. Photochemical
model runs indicate that a consistent upper limit
for Iy in the tropical UT/LS is (0.3 ± 0.1) ppt or
(0.4 ± 0.1) ppt if OIO photolysis is considered or
omitted, respectively.
Outlook/Future work More tropical observations
of gaseous and particulate iodine are necessary
to further constrain the stratospheric iodine
budget.
Funding The present work has been supported
by ESA, BMBF, DLR and the European Union.
Main publications
Butz [2006], WMO [2006]

2.2. STRATOSPHERIC RESEARCH GROUP 41
2.2.3 Trend of stratospheric bromine
Marcel Dorf (André Butz, Frank Weidner, Klaus Pfeilsticker, Martyn P. Chipperfield (University
of Leeds, UK))
Abstract Balloon-borne DOAS (Differential Optical Absorption Spectroscopy) bromine monoxide
(BrO) measurements and model simulations are used to investigate the inorganic stratospheric bromine
budget for the past 10 years.
Background Although bromine is much less
abundant than chlorine in the atmosphere, it is
known to deplete stratospheric ozone 45 to 69
times more efficiently on a per atom basis. Reactions
involving bromine contribute about half of
the seasonal polar ozone loss and about 45% of the
long-term column loss at northern mid-latitudes,
with chlorine species being largely responsible for
the remainder. There is currently great uncertainty
in the present stratospheric bromine budget,
how it has evolved over the past decade and
how it will change in the future.
Figure 2.19: Measured trends for bromine in the
near-surface troposphere (lines) and stratosphere
(squares). Global tropospheric bromine from the
sum of methyl bromide plus halons as measured in
ambient air, archived air and firn air (thick solid
line) is compared with bromine from CH3Br and
halons plus bromine from VSLS organic bromine
compounds (Br
V SLS
y
), assuming total contribu-
tions of 3, 5, or 7 ppt of these species to Bry (thin
dotted lines). Total inorganic bromine derived
from stratospheric measurements of BrO and photochemical
modeling that accounts for BrO/Bry
partitioning from slopes of Langley BrO observations
above balloon float altitude (filled squares)
and lowermost stratospheric BrO measurements
(open squares). Bold/faint error bars correspond
to the precision/accuracy of the estimates, respectively.
The years indicated on the abscissa are
sampling times for tropospheric data. For stratospheric
data, the date corresponds to the time
when the air was last in the troposphere, i.e. sampling
date minus estimated mean time in stratosphere.
Methods and results Stratospheric Bry is estimated
based on balloon-borne observations of
BrO in the middle stratosphere. These results are
combined with surface trend data of the major
stratospheric bromine source gases; methyl bromide
(CH3Br) and halons. By comparing the observed
source gas changes in the lower atmosphere
with Bry, one can determine the net contribution
to Bry from other short-lived species (BrVSLS y ) and
assess the trends in all bromine sources for the
past decade (see Figure 1). From the early 1990s
until the early 2000s, stratospheric Bry increased
from about (17.8 ± 2.5) ppt to (21.5 ± 2.5) ppt,
but in recent years this increase appears to be
slowing, consistent with restrictions on the use of
CH3Br as a fumigant. In order to explain the difference
between the sum of CH3Br plus halons and
our estimated stratospheric Bry, brominated very
short-lived species (VSLS) must also contribute
with about (4.0 ± 2.5) ppt to stratospheric Bry
on a global average. The balloon soundings presented
here reveal BrO mixing ratios typically in
the range of 0 to 2 ppt at the tropopause, with
a rapid increase above, which can only be explained
by the fast release of additional bromine
from short-lived bromine sources.
Outlook/Future work The threat of thinning
the stratospheric ozone layer by bromine may not
be over, since in a warmer climate the oceanic
emission of VSLS will possibly become accelerated.
A sea-surface temperature increase and a
concurrent increase of this additional source of
Bry is an important new aspect of atmospheric
bromine, since it potentially links climate change
occurring at the surface with the abundance of
stratospheric ozone. Thus future measurements
are needed to closely follow the trend and to quantify
the contribution of VSLS.
Funding Funding came from the BundesMinisterium
für Bildung und Forschung (BMBF), contract
DLR-50EE0017, and the European Union
through the QUILT (EVK2-2000-00545) and
SCOUT-O3 (505390-GOCE-CT-2004) projects.
Main publications
Dorf et al. [2006b], WMO [2006]

42 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.2.4 High precision measurement of the UV BrO absorption cross section
Sebastian Kreycy (André Butz, Marcel Dorf, Lena Kritten, Cristina Prados, Benjamin Simmes,
Klaus Pfeilsticker, Manfred Birk (DLR, Institut für Methodik der Fernerkundung, Oberpfaffenhofen))
Abstract The Bromine monoxide (BrO) absorption cross section will be simultaneously measured
(a) in the UV at low spectral resolution (35 cm −1 ) with the balloon DOAS instrument and (b) at high
resolution (0.002 cm −1 ) using a Fourier-Transformation (FT) spectrometer in the far-infrared. The
set of observations provides information on the BrO absorption cross section at high precision, based
on the knowledge of the BrO dipole transition matrix element (0 → 0).
Figure 2.20: Compendium of previous measurements of the temperature dependent differential
bromine monoxide cross section obtained by different groups.
Background Bromine is one of the most important
compounds acting as a catalyst in the depletion
of stratospheric ozone. Hence, it is of major
concern in atmospheric ozone research. Today
the most limiting fact in determining total
stratospheric bromine (Bry) is the knowledge of
the BrO absorption cross section which is essential
in inferring total bromine from spectroscopic
observations of stratospheric BrO.
Methods and results Absorption cross section
measurements require the knowledge of the targeted
species’ concentration within an absorption
cell. In that respect, past BrO absorption cross
section measurements based on chemical analysis
of the BrO concentration within the absorption
cell were limited. In our approach, the chemical
analysis is replaced by an in-situ optical procedure,
i. e. simultaneous observation of the BrO
cross section in the UV (300 - 380 nm) by a low
resolution DOAS spectrograph and at high resolution
in the far-IR (330 - 1000 µm), where the
line strengths of the ground-state rotational transitions
of BrO are well known. In a second experiment
aiming at thorough characterization of
the UV absorption, the BrO cross section will be
simultaneously measured at low and high resolution
whereby the low resolution measurements of
the balloon spectrometer are used as a transfer
standard.
Outlook/Future work incudes the steps:
1. Upgrading and characterization of the balloon
spectrometer.
2. Estimation of the light throughput of the
White-cell.
3. Design of the light in- and output optics.
4. Studying and recording of the curve of
growth for the BrO cross section at low and
high resolution.
5. Laboratory measurement of the BrO cross
sections
• UVlow vs IRhigh resolution
• UVlow vs UVhigh resolution
in temperature steps of 10 K ranging from
220 K to 300 K.
6. Evaluation of the data.
Funding comes through the Deutsche Forschungsgemeinschaft,
DFG (PF384/3-1).

2.2. STRATOSPHERIC RESEARCH GROUP 43
2.2.5 Photolytic lifetime of stratospheric N2O5
Lena Kritten (André Butz, Marcel Dorf, Sebastian Kreycy, Cristina Prados, Ulrike Reichl, Benjamin
Simmes, Frank Weidner, Klaus Pfeilsticker)
Abstract Time-dependent profiles of atmospheric radicals were measured in the upper troposphere
and stratosphere during the first international high-altitude balloon campaign in the tropics (Teresina,
Brazil, 5.1 ◦ S, 42.9 ◦ W). The observed diurnal variation of stratospheric NO2 [Weidner et al. , 2005]
in conjunction with photochemical modelling allows to infer the photolytic lifetime of N2O5.
Altitude / km
30
25
20
15
11 12 13 14 15 16
T ime / UT
11 12 13 14 15 16
T ime / UT
[10
17
8 molec/cm 3 ]
Figure 2.21: Measured (left side) and modelled (right side) concentration of NO2 inferred from DOAS
scanning limb observations on the LPMA/IASI payload on June 30, 2005.
Background The amount and partitioning of
stratospheric NOx (NO, NO2 and NO3) and NOy
(NOx, N2O5, HNO3, ClONO2, HO2NO2, and
BrONO2) largely govern ozone photochemistry
in the mid-stratosphere (25-40 km). During daytime,
the tropical NOx is mainly supplied by the
photochemical decay of the nighttime reservoir
N2O5. Monitoring the diurnal variation of NO2
thus provides information on the photolytic lifetime
of N2O5.
Methods and results Within the framework
of an international measurement campaign dedicated
to the ENVISAT/SCIAMACHY validation,
three stratospheric balloon flights of the
mini-DOAS scanning limb instrument were performed
aboard the MIPAS-B, LPMA/DOAS and
IASI balloon payloads in tropical latitudes near
Teresina, Northern Brazil. During all flights the
UV/Vis spectrometer recorded spectra of sunlight
scattered near the horizon in the atmosphere.
Scanning elevation angles range between 0 ◦ and
−6 ◦ with the balloons floating around 33 km altitude.
The spectral retrieval of the obtained skylight
spectra relies on the DOAS method. Pro-
NO 2
file information is then obtained using established
inversion techniques (optimal estimation
technique) in combination with a 3-D radiative
transfer model [Weidner et al. , 2005]. The obtained
profiles of O3 and NO2 are compared to
the outputs of a 1-D photochemical model, which
was initialized with trace gas observations of the
LPMA/DOAS and MIPAS payloads. From the
observed increase of stratospheric NO2 at daytime,
current estimates for the photolysis frequency
of N2O5 can be tested.
Outlook/Future work
Check the photolytic lifetime of N2O5.
Analysis of all three balloon flights at Teresina for
UV/Vis absorbing gases such as O3, NO2, BrO,
OClO, IO, OIO, and CH2O.
Preparation of, and participation in, future measurement
campaigns (at Kiruna in April 2007 and
at Teresina in Sept. 2007).
Funding comes through ESA, BMBF, DFG,
and the European Union.
15
13
11
9
7
5
3
1
-1

44 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.2.6 Measurement of upper tropospheric and lower stratospheric radicals
by balloon- and aircraft-borne scanning limb DOAS
Benjamin Simmes (Cristina Prados, Lena Kritten, Frank Weidner, Klaus Pfeilsticker)
Abstract Based on a versatile miniDOAS instrument that has been successfully tested on several
stratospheric balloon flights within the last 4 years, a new airborne miniDOAS instrument was designed
and built for the application on high flying research aircrafts like the German Falcon and HALO (DLR),
or the Russian Geophysica. The instrument aims at the detection of upper tropospheric and lower
stratospheric trace gases such as O3, NO2, CH2O, CH2O2, BrO, H2O, OClO, IO, OIO, and O4 by
means of scanning limb spectrometry of scattered skylight.
Background In the past two decades remote
sensing of the atmosphere by optical methods
has evolved into a powerful tool for meteorology,
atmospheric photochemistry and climate studies.
Quasi in-situ UV/Vis limb profiling from balloon
has proven to be a sensitive and reliable method
[Weidner, 2005]. Similar instruments on highflying
aircraft could extend the possibility of gathering
important atmospheric data regarding atmospheric
photochemistry, transport and climate.
Figure 2.22: Scanning-limb spectrometer with two
telescopes looking perpendicular to the aircraft’s
flight direction.
Instrumentation The instrument consists of
two commercial Ocean Optics grating spectrometers
for the UV and visible spectral range.
Both are kept under stable optical conditions in
a vacuum-sealed aluminum housing that is immersed
into a water-ice-bath contained in a resin
tank. Skylight is received from two telescopes that
are mounted on motorized elevation scanners to
perform limb scans perpendicular to the sun. An
embedded computer controls both spectrometers
and the telescope cradles.
Methods Skylight radiances (330 - 550 nm) are
measured up to a height of ∼ 32 km in the case
of balloons. The spectra are analyzed for column
densities along the line of sight of the chemical
species mentioned above by Differential Optical
Absorption Spectroscopy (DOAS). Radiative
Transfer (RT) calculations using the lab programmed
Monte Carlo RT Model TRACY are
used to simulate the measured absorptions and
to infer vertical profiles of targeted gases using
the Maximum a Posteriori (MAP) inversion technique.
Subsequent measurements of the profiles of
these species allow us to draw information on the
temporal and spatial variations of these species,
related photochemistry, transport and climate.
Results Balloon-borne limb scattered measurements
have been tested against simultaneous measurements
of the same parameters available from
in-situ or UV/Vis/NIR solar occultation observations
performed on the same payload. In past
studies (e. g., Weidner et al. [2005]) reasonable
agreement has been found between measured and
RT calculated limb radiances as well as between
O3, NO2, BrO and correlative profile measurements
when properly accounting for all relevant
atmospheric parameters (temperature, pressure,
aerosol extinction, and major absorbing trace
gases).
Outlook/Future work The new aircraft-borne
instrument has now been build and is awaiting
first application. Future work will focus on characterization
and benchmarking the new instrument’s
abilities and their improvement, and deployments
on the Falcon aircraft during the AS-
TAR campaign in March 2007, on balloons during
the tropical balloon campaign at Teresina/Brazil
in fall 2007 and future campaigns.
Funding comes through the Deutsche Forschungsgemeinschaft,
DFG (PF384/5-1).

2.2. STRATOSPHERIC RESEARCH GROUP 45
References
Bösch, H., Camy-Peyret, C., Chipperfield, M. P., Fitzenberger, R., Harder, H., Platt, U., & Pfeilsticker,
K. 2003. Upper limits of stratospheric IO and OIO inferred from center-to-limb-darkeningcorrected
balloon-borne solar occultation visible spectra Implications for total gaseous iodine and
stratospheric ozone. J. Geophys. Res., 108, 4455.
Butz, A. 2006. Case studies of stratospheric nitrogen, chlorine and iodine photochemistry based on
balloon-boren UV/visible and IR absorption spectroscopy. PhD Thesis, Universität Heidelberg.
Butz, A., Bösch, H., Camy-Peyret, C., Chipperfield, M. P., Dorf, M., G., Dufour, Grunow, K., Jeseck,
P., Kühl, S., Payan, S., Pepin, I., Pukite, J., Rozanov, A., von Savigny, C., Sioris, C., Weidner,
F., & Pfeilsticker, K. 2006a. Inter-comparison of stratospheric O3 and NO2 abundances retrieved
from balloon borne direct sun observations and Envisat/SCIAMACHY limb measurements. Atmos.
Chem. Phys., 6, 1293–1314.
Butz, A., Bösch, H., Camy-Peyret, C., Dorf, M., Engel, A., Payan, S., & Pfeilsticker, K. 2006b.
Observational constraints on the kinetics of the ClO-BrO and ClO-ClO ozone loss cycles in the
Arctic winter stratosphere. Geophys. Res. Lett. submitted.
Dorf, M., Bösch, H., Butz, A., Camy-Peyret, C., Chipperfield, M. P., Engel, A., Goutail, F., Grunow,
K., Hendrick, F., Hrechanyy, S., Naujokat, B., Pommereau, J.-P., Van Roozendael, M., Sioris, C.,
Stroh, F., Weidner, F., & Pfeilsticker, K. 2006a. Balloon-borne stratospheric BrO measurements:
Comparison with Envisat/SCIAMACHY BrO limb profiles. Atmos. Chem. Phys., 6, 2483–2501.
Dorf, M., Butler, J. H., Butz, A., Camy-Peyret, C., Chipperfield, M. P., Kritten, L., Montzka, S. A.,
Simmes, B., Weidner, F., & Pfeilsticker, K. 2006b. Long-term observations of stratospheric bromine
reveal slow down in growth. Geophys. Res. Lett., 33, L24803. doi:10.1029/2006GL027714.
Feng, W., Chipperfield, M. P., Dorf, M., & Pfeilsticker, K. 2006. Mid-latitude Ozone Changes: Studies
with a 3-D CTM Forced by ERA-40 Analyses. Atmos. Chem. Phys. Discuss., 6, 6695–6722.
Frieler, K., Rex, M., Salawitch, R. J., Canty, T., Streibel, M., Stimpfle, R. M., Pfeilsticker, K., Dorf,
M., Weisenstein, D. K., & Godin-Beekmann, S. 2006. Towards a better quantitative understanding
of polar stratospheric ozone loss. Geophys. Res. Lett., 22. doi:10.1029/2005GL025466.
Reichl, U. 2005. Ground-based direct Sun UV/vis spectroscopy in Timon, Northeastern Brazil: Comparison
of tropospheric air mass pollution in the dry and wet season. Diploma Thesis, Universität
Heidelberg.
Schwärzle, J. 2005. Spektroskopische Messung von Halogenoxiden in der marinen atmosphärischen
Grenzschicht in Alcântara, Brasilien. Staatsexamensarbeit, Universität Heidelberg.
Sioris, C. E., Kovalenko, L. J., McLinden, C. A., Salawitch, R. J., Van Roozendael, M., Goutail,
F., Dorf, M., Pfeilsticker, K., Chance, K., von Savigny, C., Liu, X., Kurosu, T. P., Pommereau,
J.-P., Bösch, H., & Frerick, J. 2006. Latitudinal and vertical distribution of bromine monoxide in
the lower stratosphere from SCIAMACHY limb scattering measurements. J. Geophys. Res., 111,
D14301. doi:10.1029/2005JD006479.
Solomon, S., Garcia, R., & Ravishankara, A. 1994. On the role of iodine in ozone depletion. J. Geophys.
Res., 99, 20491–20499.
Weidner, F. 2005. Development and Application of a Versatile Balloon-Borne DOAS Spectrometer
for Skylight Radiance and Atmospheric Trace Gas Profle Measurements. PhD Thesis, Universität
Heidelberg.
Weidner, F., Bösch, H., Bovensmann, H., Burrows, J. P., Butz, A., Camy-Peyret, C., Dorf, M.,
Gerilowski, K., Gurlit, W., Platt, U., von Friedeburg, C., Wagner, T., & Pfeilsticker, K. 2005.
Balloon-borne Limb profiling of UV/vis skylight radiances, O3, NO2, and BrO: Technical set-up
and validation of the method. Atmos. Chem. Phys., 5, 1409–1422.
WMO (ed). 2006. Scientific Assessment of Ozone Depletion: 2006. World Meteorological Organization
Global Ozone Research and Monitoring Project: Geneva.

2.3. RADIATIVE TRANSFER 47
2.3 Radiative Transfer
Klaus Pfeilsticker
Group members
Prof. Dr. K. Pfeilsticker, Head of group
C. Fensterer, Diploma Student
Dr. A. Lotter, Post Doc
Dr. T. Scholl, left by July 2006
Abstract
Our research on the radiative transfer (RT) in the Earth’s atmosphere concentrates on an improved
understanding of the UV/Vis solar irradiance, its temporal variation, and the deposition of solar radiation
in the atmosphere. These studies include spectroscopic measurements from different platforms
and sophisticated radiative transfer modelling.
Scientific objectives
• Measurements of path length distributions of solar photons being transmitted to the ground
[Scholl et al. , 2006]
• The absolute spectral solar irradiance (320 - 650 nm) and its temporal variation [Lindner, 2005;
Gurlit et al. , 2005; Weidner et al. , 2005]
• Measurements of UV/Vis actinic fluxes, e. g. JNO2, and the limb radiance near horizon
• The detection and characterization of unknown, overlooked, or yet poorly characterized atmospheric
absorbers such as H2O continuum absorption, metastable and stable H2O–H2O dimers,
or the collisional complex O2–O2 [Lotter, 2006]
• Measurements of the stratospheric aerosol extinction and its relation to volcanic eruptions, the
formation of polar stratospheric clouds, and aerosols of the tropical upper troposphere and lower
stratosphere
• Validation of level 1 products (spectral solar irradiance, limb radiances) of the SCIAMACHY
instrument deployed on the European research satellite ENVISAT [Weidner et al. , 2005]
Background
The transfer of solar radiation in the Earth’s atmosphere is one of the most complicated issues in
environmental sciences mostly due to the variety and complex nature of atmospheric absorbers and
scatterers (e. g., gases, aerosols, liquid and solid cloud particles), their spectroscopic signatures, and
their varying spatial arrangements. Accordingly it is found that clear and cloudy sky radiative transfer
is the major uncertainty in climate modelling, thus the validation of RT models appears to be necessary.
RT models are also used for photochemical investigations and for in-situ and remote sensing studies.
Main methods
Methods used for the investigation of radiative transfer involve: (1) The study of absolute spectral
solar irradiance in the UV/Vis/NIR region and the corresponding near horizon skylight limb radiances
measured by different grating- and Fourier-Transformation-spectrometers deployed on high altitude
(∼ 40 km) balloon platforms. These measurements include on-site absolute radiometric calibration
to NIST (National Institute of Standard and Technology, USA) and PTB (Physikalische Technische
Bundesanstalt) radiometric standards; (2) Ground-based spectroscopy of zenith scattered skylight
of the oxygen A-band (767 - 771 nm) at high spectral resolution (see upper panel of Figure 2.23) to
receive path length distributions of solar photons for a variety of cloudy skies (see lower panel of
Figure 2.23); (3) Near-surface long path absorption spectroscopy in wavelength intervals ranging from
the UV to the NIR. All the instruments are deployed on internationally organized field campaigns
that address a wider range of scientific objectives. The interpretation of these measurements also
involves sophisticated radiative transfer modelling (ray-tracing, Monte Carlo, discrete ordinate models,
DISORT) that, for example, accounts for the sphericity of the atmosphere, refraction, cloud cover,
and time and space dependent trace gas and aerosol concentrations.

48 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Figure 2.23: Upper panel: Comparison of measured (black) and simulated (red) oxygen A-band
spectrum for the observation at Cabauw (NL) on May 11, 2003 at UT 14:59. The identification of the
oxygen A-band and solar Fraunhofer lines is given next to the respective lines. Middle panel: Residual
spectrum taken as the natural logarithm of the ratio of measured and simulated spectrum, hence the
natural units of vertically integrated optical density (VOD) or air-mass. Lower panel: Inferred photon
path PDF, assuming a Γ-distribution for the in-cloud transfer (adopted from Scholl et al. [2006]).
Main activities
The activities in 2006 concentrated on the dissemination of the results obtained in past studies.
Cooperation within the institute and with groups outside the institute
Activity (1) as given in methods has been performed within a French-German collaboration with the
Laboratoire de Physique Moléculaire et Applications, Université Pierre et Marie Curie, Paris and
within a collaboration with the IUP at the University of Bremen, Germany. Activity (2) has been
carried out within the framework of the 4-D Cloud project in cooperation with eight institutions
(DWD, Deutscher Wetterdienst, Observatorium Lindenberg; GKSS, Forschungszentrum Geesthacht;
IfM, Institut für Meereskunde, Universität Kiel; IfT, Institut für Troposphärenforschung, Leipzig; IPA,
Institut für Physik der Atmosphäre, Universität Mainz; MIUB, Meteorologisches Institut, Universität
Bonn; MPI-M, Max-Planck-Institut für Meteorologie, Hamburg; TUD, Technische Universität Dresden).
Finally, activity (3) has been performed within a cooperation with partners from the University
of Grenoble, France and the Brazilian military.

2.3. RADIATIVE TRANSFER 49
Future work
• Improved measurements of the solar irradiance in the UV-A and UV-B (λ > 242 nm)
• 2-D mapping of cloud properties by imaging DOAS (IDOAS) from the ground
• Improved spectral retrieval of water vapor, water continuum, and water dimer absorption in the
Vis/NIR spectral region (600 - 750 nm)
• A feasibility study of aircraft-borne spectrometry of gaseous, liquid and ice water path
Peer Reviewed Publications
1. Scholl et al. [2006]
PhD Theses
1. Lotter [2006]
2. Scholl [2006]

50 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.3.1 2-D mapping of cloud parameters
Claudia Fensterer (Klaus-Peter Heue, Andreas Lotter, Klaus Pfeilsticker)
Abstract The present diploma study is concerned with the development of a 2-D imaging spectrometer
to monitor the temporal and spatial changes of optical properties of clouds (e. g. the cloud
optical density and photon path lengths). The observations will be performed by monitoring the
zenith sky radiances and Vis/NIR absorptions of O2, O4 and H2O, the spectroscopic data retrieval
will be carried out using the DOAS technique.
Figure 2.24: Principle of Imaging Spectroscopy
(IDOAS): (A) The spectrum of a volcano plume
is observed by an imaging spectrometer equipped
with a CCD-detector. (B-C) The spectra are
recorded line-wise and the optical density of atmospheric
absorbers are visualized (here SO2 and
in future O2, O4 and H2O). (D) The second spatial
dimension is monitored by scanning the entrance
slit across the targeted field of view.
Background In climate modelling a reasonable
representation of clouds and their impact on the
absorption of solar radiation is still a challenging
task. In particular, sub-grid variability of clouds
is not well understood. Therefore, the primary
goal of the present study is to investigate cloud
parameters (cloud optical density, photon path
lengths, gaseous absorption) in two dimensions on
spatial scales commensurate with radiative transfer
(from 100 m to kilometers). For this purpose
two-dimensional maps of the optical density of O2,
O4 and H2O as a tracer for photon path lengths
and cloud optical density are inferred from spectroscopic
observations of skylight radiance in a
wavelength range from 400 to 800 nm.
Methods and Results The method relies on
the 2-D spectroscopy of atmospheric trace gases
using the Differential Optical Absorption Spectroscopy
(DOAS) technique. Past experiences
have shown [Lohberger, 2003; Louban, 2005], that
most challenging in the 2-D imaging of atmospheric
trace gases are (a) a sufficiently high wavelength
dispersion, (b) an excellent focus of the slit
image on the detector in the observed first spatial
dimension, and (c) a good estimate of the field of
view in the scanning (second) spatial dimension.
Accordingly, most of the work of the present study
has been invested to improve, optimize, and characterize
an existing imaging spectrometer.
In particular, for the present study a spectrometer
is adapted to monitor skylight in the wavelength
range between 400 and 800 nm where the most important
trace gas absorptions (O2, O3, O4, NO2
and H2O) for cloud studies are found. Upgrading
this spectrometer is still under way. Meanwhile
and in parallel another existing spectrometer
previously used for aircraft measurements
[Heue, 2005] is being deployed in the field and first
results are expected to be obtained soon.
Outlook/Future work Future work includes
(a) to set up a lab-based spectrometer for the
400 and 800 nm holographic concave grating and
to find an optimal imaging, (b) to transfer the
lab set-up into a field usable housing including
temperature stabilization in order to maintain the
wavelength calibration, and (c) to deploy the aircraft
instrument in the field for cloud observations.
Funding The project is funded by the DLR,
’Virtuelles HALO Institut’.

2.3. RADIATIVE TRANSFER 51
2.3.2 Field measurements of water continuum and water dimer absorption
Andreas Lotter (Klaus Pfeilsticker)
Abstract Long path length atmospheric absorption spectra of the 4ν, 4ν+δ, and 5ν water polyads
are analyzed for water continuum and water dimer absorption. The measured water continuum
absorption agrees with two versions of the semi-empirical CKD model by order of magnitude. An
upper limit of KP(301 K) = 0.055 atm −1 is inferred for the water dimer equilibrium constant.
optical depth
1.2
1.1
1.0
0.9
CKD_2.4.1
MT_CKD_1.0
residual: measurement - H 2 O monomer (HITRAN04)
H 2 O dimer
Ma and Tipping
700 710 720 730 740 750
wavelength (nm)
Figure 2.25: Residual between measurement and
HITRAN04 water monomer reference. The predicted
water continuum absorption by the Ma and
Tipping far wing line shape theory [Ma & Tipping,
1999] and two versions of the semi-empirical CKD
model [Clough et al. , 1989] are superimposed.
Also shown is the calculated water dimer absorption
based on the absorption cross section by
Schofield & Kjaergaard [2003] and a water dimer
equilibrium constant of KP(301 K) = 0.055 atm −1 .
Background Since atmospheric water vapor
strongly absorbs the incoming solar shortwave and
the outgoing thermal infrared radiation, the exact
knowledge of the spectroscopic signature of water
vapor is of central importance for climate research.
Superimposed on the water monomer absorption
a water continuum absorption has been
recognized for a long time, but its true nature is
still controversial. On the one hand, water continuum
absorption is explained by a deformation
of the line shape of water monomer absorption
lines as a consequence of molecular collisions. On
the other hand, truly bound and metastable water
dimers possibly contribute to water continuum
absorption, too.
Methods and results The spectra recorded by
an active Long Path DOAS instrument during
three field measurement campaigns in the midlatitudes
and the tropics (absorption path lengths:
18 - 29 km, ambient water vapor partial pressures:
7 - 29 mbar) are analyzed for water continuum and
water dimer absorption. The 4ν, 4ν+δ and 5ν water
polyads in the visible and near-infrared spectral
region are selected for the measurements as
three water dimer absorption bands are predicted
to exist almost free of interference by strong water
monomer absorption bands [Schofield & Kjaergaard,
2003]. For a firm evidence of water dimer
absorption a quadratic dependence on the water
monomer absorption has to be verified.
In this context our report of the first detection
of atmospheric water dimers [Pfeilsticker et al. ,
2003] has to be reconsidered as these results can
not be confirmed by subsequent measurements,
especially by those carried out in the tropics. It
is shown that the quality of existing spectral line
databases (e. g., HITRAN, ESA-WV, Partridge-
Schwenke) is insufficient to provide accurate water
monomer references in order to confidently detect
superimposed water dimer absorption. Therefore,
only an upper limit of water dimer absorption
is obtained resulting in the upper limit
of the water dimer equilibrium constant being
KP(301 K) = 0.055 atm −1 . The water dimer band
FWHM is, at least, 40 cm −1 .
The measured water continuum absorption and
the predictions by the semi-empirical CKD 2.4.1
and MT CKD 1.0 water continuum models
[Clough et al. , 1989] are of the same order of
magnitude. In contrast, the Ma and Tipping far
wing line shape theory [Ma & Tipping, 1999] underestimates
water continuum absorption by one
order of magnitude in the 4ν and 5ν water bands,
and by two orders of magnitude in the 4ν+δ water
band. Based on the present state of knowledge
about the spectroscopic and thermochemical
properties of the water dimer, its contribution to
the observed water continuum absorption in the
visible and near-infrared spectral region is minor.
Outlook/Future work For the detection of
water dimers the theoretical Long Path DOAS
detection limit could not be achieved due to the
inaccuracy of existing water vapor spectral line
databases in the 4ν, 4ν+δ, and 5ν spectral regions.
High resolution measurements of the water
monomer spectrum are required with an extinction
as low as 10 −10 cm −1 , in order to benefit from
the full power of the Long Path DOAS technique.
Funding came through the Deutsche Forschungsgemeinschaft,
DFG (PF384/2-1 and 2-3).
Main publication Lotter [2006]

52 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.3.3 Oxygen A-band measurements for solar photon path length distribution
studies
Thomas Scholl (Klaus Pfeilsticker)
Abstract High resolution spectroscopy of the oxygen A-band (760 - 780 nm) in zenith scattered
skylight is a powerful tool to infer path length distributions of solar photons transmitted to the
ground. The relation between the moments 〈L〉 and 〈L 2 〉 of the probability density function (PDF)
and the rescaled cloud optical depth τ ∗ is a strong indicator for 3-D effects on radiative transfer (RT).
Height [m]
10000
8000
6000
4000
2000
0 :0
12:
:5 :10 :15 :20 :25 :30 :35 :40 :45 :50 :55
Time [UTC]
-60 -50 -40 -30 -20 -10 0 10 20
Reflectivity [dBZ]
Figure 2.26: Left panel: Measured radar reflectivities from KNMI 35 GHz Radar for May 22, 2003
UT 12:00-13:00; Right panel: Mean cloud photon paths 〈Lc〉 as a function of effective cloud optical
depth τ ∗ c . The black lines are predictions for different values of the Lévy index α ≤ 2. The three data
clusters (color-coded blue, red and green) correspond to the three different probed cloud situations.
Background Modelling the radiative transfer
in cloudy skies is one of the most challenging tasks
in climate research. The photon PDF is commonly
a hidden property of standard RT models
controlled by the spatial distribution of scattering
and absorption. Since the scattering properties
of clouds and aerosols vary slowly and predictably
with wavelength, the principle of equivalence
allows to draw conclusions about radiative
properties of the atmosphere from a photon PDF
measured in one wavelength band. The photon
PDF in the near-infrared region is very representative
for the shortwave region as a whole. In
the study of Scholl et al. [2006], the first two
moments of the PDF of solar photons transmitted
through cloudy skies to the ground are investigated.
Combining the spectroscopic measurements
with other cloud properties measured
simultaneously by in-situ techniques during two
campaigns allowed to test the theory of anomalous
photon diffusion through clouds.
Methods and Results The multiple of different
line strengths offered by the oxygen A-band
implicitly provide direct information on the PDF
of the photons transmitted to the ground. The
spectral retrieval is solved by forward modelling
the measured spectra with a prescribed photon
PDF (usually a Γ-function) at high spectral resolution.
Then the free parameters of the PDF
are iteratively calculated by using a nonlinear
least square fit leading to the searched quantities
〈L〉 and 〈L 2 〉. Davis & Marshak [2002] inferred
for the first moment of the photon PDF:
〈Lc〉/∆H = (1/2 · [1 + C(ɛ)] · τ ∗ ) α−1 , with α being
the Lévy index ranging between 1 and 2. In
particular, the value α = 2 is attained for a homogenous
slab and α < 2 for a inhomogeneous
slab. In Figure 2.26 the enhancement of the mean
photon path length in the cloud (as a function of
τ ∗ = τ · (1 − g)) and the received Lévy indices are
shown.
The findings confirm the theory of anomalous photon
diffusion through clouds and the predictions
for the values in the path length to optical depth
relations. It also provides further evidence that
cloudy sky photon path length require consideration
of non-classical photon transport theory.
Outlook/Future work Photon PDFs are a
central concept of cloud radiative transfer modelling.
For further improvements imaging DOAS
spectroscopy at high temporal and spatial resolution
is required.
Funding came through the AFO-2000 4-D
Cloud project (BMBF-07ATF24).
Main publications
Scholl [2006], Scholl et al. [2006]

2.3. RADIATIVE TRANSFER 53
References
Clough, S. A., Kneizys, F. X., & Davies, R. W. 1989. Line shape and water vapor continuum. Atmos.
Res., 23, 229–241.
Davis, A. B., & Marshak, A. 2002. Space-Time Characteristics of Light Transmitted through Dense
Clouds: A Green’s Function Analysis. J. Atmos. Sci., 59, 2713–2727.
Gurlit, W., Bösch, H., Bovensmann, H., Burrows, J. P., Butz, A., Camy-Peyret, C., Dorf, M., Gerilowski,
K., Lindner, A., Noël, S., Platt, U., Weidner, F., & Pfeilsticker, K. 2005. The UV-A
and visible solar irradiance spectrum: Inter-comparison of absolutely calibrated, spectrally medium
resolved solar irradiance spectra from balloon-, and satellite-borne measurements. Atmos. Chem.
Phys., 5, 1879–1890.
Heue, K.-P. 2005. Airborne Multi AXis DOAS instrument and measurements of two-dimensional
tropospheric trace gas distributions. PhD Thesis, Universität Heidelberg.
Lindner, A. 2005. Ballongestütze Messungen der extraterrestrischen spektralen solaren Irradianz.
Diploma Thesis, Universität Heidelberg.
Lohberger, F. 2003. Imaging Spectroscopy of Atmospheric Trace Gases. Diploma Thesis, Universität
Heidelberg.
Lotter, A. 2006. Field Measurements of Water Continuum and Water Dimer Absorption by Active
Long Path Differential Optical Absorption Spectroscopy (DOAS). PhD Thesis, Universität Heidelberg.
Louban, I. 2005. Zweidimensionale Spektroskopische Aufnahmen von Spurenstoff-Verteilungen.
Diploma Thesis, Universität Heidelberg.
Ma, Q., & Tipping, R. H. 1999. The averaged density matrix in the coordinate representation:
Application to the calculation of the far-wing line shapes for H2O. J. Chem. Phys., 111, 5909–
5921.
Pfeilsticker, K., Lotter, A., Peters, C., & Bösch, H. 2003. Atmospheric Detection of Water Dimer Via
Near-Infrared Absorption. Science, 300, 2078–2080.
Schofield, D. P., & Kjaergaard, H. G. 2003. Calculated OH-stretching and HOH-bending vibrational
transitions in the water dimer. Phys. Chem. Chem. Phys., 5, 3100–3105.
Scholl, T. 2006. Photon Path Length Distributions for Cloudy Skies - Their first and second-order
moments inferred from high resolution oxygen A-Band spectroscopy. PhD Thesis, Universität Heidelberg.
Scholl, T., Pfeilsticker, K., Davis, A. B., Klein Baltink, H., Crewell, S., Löhnert, U., Simmer, C.,
Meywerk, J., & Quante, M. 2006. Path length distributions for solar photons under cloudy skies:
Comparison of measured first and second moments with predictions from classical and anomalous
diffusion theories. J. Geophys. Res., 111, D12211. doi:10.1029/2004JD005707.
Weidner, F., Bösch, H., Bovensmann, H., Burrows, J. P., Butz, A., Camy-Peyret, C., Dorf, M.,
Gerilowski, K., Gurlit, W., Platt, U., von Friedeburg, C., Wagner, T., & Pfeilsticker, K. 2005.
Balloon-borne Limb profiling of UV/vis skylight radiances, O3, NO2, and BrO: Technical set-up
and validation of the method. Atmos. Chem. Phys., 5, 1409–1422.

2.4. SATELLITE GROUP 55
2.4 Satellite Group
Group members
Prof Dr. T. Wagner, head of group
Dr. Steffen Beirle, Post Doc
Tim Deutschmann, student
Barbara Dix, PhD student
Dr. Christian Frankenberg, Post Doc
Michael Grzegorski, PhD student
Michael Hayn, Diploma student
Dr. Klaus-Peter Heue, Post Doc
Dr. Jens Hollwedel, Post Doc
Ossama Ibrahim, PhD student
Dr. Muhammad Fahim Khokhar, Post Doc
Dr. Sven Kühl, Post Doc
Dr. Thierry Marbach, Post Doc
Janis Pukite, PhD student
Suniti Sanghavi, PhD student
Abstract
The Satellitegroup is part of the research group Atmospheric Physics of Prof. Dr. Ulrich Platt.
The satellite born remote sensing of the Earth’s atmosphere at the University of Heidelberg started
in 1996 with the retrieval of atmospheric trace gases, namely NO2 and BrO. Today a wide variety of
trace gases and other atmospheric parameters (Aerosols, Clouds, Radiative Transfer) from different
satellite instruments are investigated at the IUP (see also http://satellite.iup.uni-heidelberg.de). In
October 2006 part of the satellite group moved to the Max-Planck-Institute for Chemistry in Mainz.
The group is since then referred to as ’Satellite group Mainz-Heidelberg’.
Scientific Objectives
Since about 10 years now, a new generation of UV/vis/NIR satellite instruments (GOME, SCIA-
MACHY, OMI) with moderate spectral resolution allows the retrieval of a large variety of atmospheric
trace gases. In particular, global maps of several tropospheric trace gases like O3, BrO, NO2, CO,
CH4, CO2, HCHO, SO2, H2O, O2, O4, and cloud properties can be analysed from observations in
nadir viewing mode. The most important advantage of such satellite observations is their spatial (horizontal)
coverage and resolution. The newest generation of nadir looking UV/vis satellite instruments
(e.g. OMI) achieves global coverage within one day and has a horizontal resolution of about 13 x 24
km. From such satellite observations, various individual sources like large cities can be identified. In
addition, the observation of scattered sun light in limb geometry allows to retrieve vertical profiles of
several stratospheric trace gases like O3, NO2, BrO and OClO.

56 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Figure 2.27: The timeline of continuous novel UV/vis/NIR satellite measurements starts in April
1995 with GOME (1) on ERS-1. With its successors it will hopefully cover a total period of more
than 25 years.
Main activities
How are single projects linked, list/group the subprojects
The various projects can be classified according to their spectral range, viewing geometry, and
analysis method.
- UV/vis DOAS for Nadir viewing geometry The main target is the determination of global maps
of tropospheric trace gas distributions like NO2, BrO, H2O, HCHO, SO2, Glyoxal. Currently measurements
of GOME and SCIAMACHY are under investigation.
- NIR DOAS for Nadir viewing geometry The main target is the determination of global maps of
tropospheric trace gas distributions like CH4, CO2, and CO. Measurements in the near IR spectral
range are carried out only by SCIAMACHY.
-Cloud retrieval for Nadir viewing geometry The main target is the determination of global maps of
cloud cover (effective cloud fraction) from broad band spectral measurements. From the combination
with narrow band absorption measurements of O2 and O4, also additional parameters like cloud top
height can be retrieved.
-UV/vis DOAS for limb viewing geometry The main target is the determination of vertical profiles
of stratospheric trace gases like O3, NO2, BrO, and OClO. Measurements in limb viewing geometry
are carried out only by SCIAMACHY.
-3-D radiative transfer modelling Detailed radiative transfer modelling is the prerequisite for the
correct interpretation of the results of the spectral analysis. The full spherical 3-dimensional Monte
Carlo model is developed and operated in our group. Also a detailed scheme for the simulation of
radiative properties of aerosols is developed.
-Validation of satellite data with independent observations DOAS observations are carried out
from several ground based stations (Kiruna, Paramaribo, Neumayer) as well as from aircrafts and
ships.
Methods and results From the measured spectra, the narrowband absorption features of several
trace gases are analysed using the DOAS method. The result of the spectral analysis represents the
trace gas absorption integrated along the absorption path. In addition, also the broad band spectral
features are analysed; they yield information in particular on the cloud cover, aerosol load and ground
albedo (in particular also vegetation cover). Various algorithms for the analysis of satellite spectra
were developed in the satellite group within the last years. For the detailed interpretation of the
analysed spectral information, radiative transfer modelling is needed. A 3-D Monte-Carlo radiative
transfer model (TRACY-II) was developed in our group, which allows to simulate various complex
viewing geometries and atmospheric properties. The retrieved global data sets are further investigated
using image sequence techniques.

2.4. SATELLITE GROUP 57
Funding
The group activities are funded through various national and international projects, e.g. EVER-
GREEN, NOVAC, STAR, Tropische Tropopause, ACCENT
Cooperation within the institute and with groups outside of the institute
Intensive interaction and cooperation exists with various international groups, e.g. Uni-Bremen,
IASB Brussels, Uni Mnchen, SRON Utrecht, KNMI Utrecht, EUMETSAT
Future Work
The data analysis will be continued and in particular observations from new instruments (OMI,
GOME-2) will be included.
Peer Reviewed Publications
1. Beirle et al. [2006b]
2. Bergamaschi et al. [2006]
3. Bruns et al. [2006]
4. Butz et al. [2006]
5. Dils et al. [2006]
6. Frankenberg et al. [2006]
7. Frie et al. [2006]
8. Frins et al. [2006]
9. Grzegorski et al. [2006]
10. Hendrick et al. [2006]
11. Loyola et al. [2006]
12. Toenges-Schuller et al. [2006]
13. Wagner et al. [2006e]
14. Wagner et al. [2006j]
15. Wang et al. [2006]
16. Wittrock et al. [2006]
Other Publications
1. Beirle et al. [2006a]
2. Deutschmann & Wagner [2006]
3. Hendrick et al. [2006]
4. Kühl et al. [2006a]
5. Kühl et al. [2006b]
6. Marbach et al. [2006a]
7. Marbach et al. [2006b]
8. Marbach et al. [2006c]

58 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
9. Marbach et al. [2006d]
10. Pukite et al. [2006b]
11. Pukite et al. [2006c]
12. Pukite et al. [2006a]
13. Sinreich et al. [2006]
14. Wagner et al. [2006d]
15. Wagner et al. [2006c]
16. Wagner et al. [2006f]
17. Wagner et al. [2006g]
18. Wagner et al. [2006h]
19. Wagner et al. [2006b]
20. Wagner et al. [2006i]
21. Wagner et al. [2006a]
Diploma Theses
PhD Theses
1. Khokhar [2006]

2.4. SATELLITE GROUP 59
2.4.1 Satellite observations of Glyoxal
Steffen Beirle (Ulrich Platt, Thomas Wagner)
Abstract Spectral measurements from the satellite instrument SCIAMACHY allow to determine
column densities of several important atmospheric absorbers. Recently, the absorption strucures of
Glyoxal have also been detected in satellite spectra. The mean global glyoxal distribution derived
from SCIAMACHY indicates several photochemical hotspots due to anthropogenic emissions as well
as biogenic and biomass burning VOC emissions.
Figure 2.28: Mean Glyoxal SCD (10 15 molec/cm 2 ) from SCIAMACHY (2003 - 2005).
Background Glyoxal (C2H2O2) is formed by
the oxidation of several volatile organic compounds
(VOCs) and hence serves as an important
indicator for fast VOC chemistry. Glyoxal has
characteristic absorption bands in the blue spectral
range, allowing remote sensing by Differential
Optical Absorption Spectroscopy (DOAS). Here
we present the results of our Glyoxal retrieval from
SCIAMACHY spectra.
Methods and results The DOAS fit has been
implemented for the evaluation of Glyoxal in the
spectral range 436-457 nm. Fig. 2.28 shows the
resulting mean of the global distribution of Glyoxal.
Photochemical hot spots due to anthropogenic
activities can clearly be identified, for instance
Hong Kong or Los Angeles. Also strong biomass
burning events lead to enhanced Glyoxal levels,
e.g. in Brasilia. Generally, the detected Glyoxal
column densities are high over the tropical
rain forest, indicating biogenic VOC emissions.
Also over some bioactive oceanic regions enhanced
Glyoxal levels are found, possibly indicating VOC
emissions over ocean.
Outlook/Future work Future efforts will have
to be taken to come to more quantitative statements.
Especially over oceanic regions, the DOAS
fit has to be improved, involving high resolved
spectral structures of liquid water and chlorophyll
absorption.
Ongoing measurements from SCIAMACHY
and also GOME-2, launched in November 2006,
will lead to reduced statistical errors and will allow
to assess several scientific questions like spatial
distributions and/or seasonal cycles of VOC
emissions or to distinguish between VOC and NOx
limited summer smog regimes.
Funding DFG / ’Eigene Stelle’.
Main publication Wittrock et al. [2006]

60 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.4.2 Development of a Radiative Transfer Forward Model
Tim Deutschmann (Thomas Wagner, Ulrich Platt)
Abstract Radiative transfer modelling (RTM) plays a key role in profile retrieval of atmospheric
trace gases and correct interpretation of spectral measurement results provided by remote sensing
techniques. The developed model is applicable to a manifold of different measurement geometries,
and allows realistic modelling of the transfer process using a Monte Carlo method.
Figure 2.29: Backward trajectory scatter events. Red/Blue: rayleigh/raman s.e., yellow: ground s.e.,
green: aerosol s.e.. Left: measurement from inside a caldera at 360 nm with aerosol layer (1.15km-
1.35km). Center: measurement of a volcanic plum from satellite at 440 nm. Right: The plum as
measured from the ground.
Background Various remote sensing techniques
that use satellites, are ground based or
airborne provide spectra in UV-VIS spectral
range. Applying the DOAS (Differential Optical
Absorption Spectroscopy) method, slant column
densities of several absorbing species can be extracted
from the raw spectra. The slant column
of a trace gas is a path integral of its number density
along the light path. Due to multiple scattering
on air molecules, scattering and absorption on
aerosol particles and absorption by trace gases the
light path is complex. For the inversion of trace
gas profiles, the radiative transfer process must be
modelled using a so called forward modell.
Funding HiWi, soon Diploma Thesis.
Methods and Results The most flexible
method to solve the equation of transfer is the
Monte Carlo method. Using random numbers,
photon trajectories, which obey the physical transition
densities are generated. The developed
modell TRACY-II uses the Backward Monte
Carlo method, which exploits the reciprocity of
the transfer process to generate the trajectories.
Each scatter event of the backward trajectory represents
a physical light path by completing the
light path from the scatter event to the sun. The
amount of sun photons taking this path is measured
by calculating a corresponding weight. The
weight is the product of probabilities, that 1. the
sun photon reaches the first scatter event and 2.
takes the path into the direction of the next scatter
event resp. the detector. Using this formalism
various quantities like intensities, weighting
functions or simulated slant column densities are
calculated.
The existing model was validated during the
ACCENT RTM workshop on 12th of June 2006
and showed excellent agreement with other modells.
Preliminary comparisons with balloon measurements
showed agreement within the measurement
error.
Outlook/Future Work In near future the calculation
of partial derivatives will be focused, in
order to investigate instrument sensitivity on different
parameters. A promising possibility of information
retrieval from measurement is to take
polarization of light by scattering into account.
The models flexibility allows applications in a
wide range of investigations, not only in UV-VIS
spectral range but also in IR.
Main Publication Deutschmann & Wagner
[2006] Wagner et al. [2006d]

2.4. SATELLITE GROUP 61
2.4.3 Retrieval of cloud parameters using SCIAMACHY and GOME data
Michael Grzegorski (Thomas Wagner 1 , Tim Deutschmann, Mark Wenig 2 , Ping Wang 3 , Piet
Stammes 3 )
1 also at Max Planck Institute for chemistry, Mainz
2 NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
3 Royal Meteorological Institute of the Netherlands, KNMI, Utrecht, The Netherlands
Abstract The retrieval of cloud parameters like cloud coverage, cloud top pressure or cloud optical
thickness from satellite is an important issue both for climatology and the analysis of tropospheric
trace gases. The HICRU algorithm improves retrieval of effective cloud fraction using data from
SCIAMACHY on ENVISAT and GOME on ERS-2. The combination of HICRU data with the DOAS
evaluation of O 2 and O 4 allows the retrieval of further cloud parameters.
Figure 2.30: RGB image of the cloud free earth retrieved by HICRU applied to SCIAMACHY data.
The PMD4 (805-900 nm) is used as green channel, because the PMD instruments only provide blue
and red in the visual wavelength bands.
Background The detection of cloud parameters
like cloud coverage, cloud top pressure or
cloud optical thickness from satellite is an important
issue: 1.) for meteorology and the investigation
of climate change and 2.) for the analysis of
tropospheric trace gases from space relevant to environmental
and climatological issues. Although
the retrieval of different cloud parameters is useful
for trace gas retrievals, especially the accurate
identification of completely cloud free regions is
crucial due to the shielding effect, which causes
an underestimation of the vertical column density
of tropospheric trace gases measured by satellite.
Methods and results The Heidelberg Iterative
Cloud Retrieval Utilities (HICRU) retrieve effective
cloud fraction by applying the widely used
threshold method combined with image sequence
analysis and an iterative approach to the socalled
Polarization Monitoring Devices (PMDs)
with higher spatial resolution compared to the
channels used for trace gas retrievals. The algo-
rithm is published in 2006 and was part of validation
studies for the official SCIAMACHY data
product. These studies show the improvement of
HICRU compared to other cloud algorithms, especially
over deserts. Problems of the next release
of the official data product from ESA are worked
out. A DOAS evaluation of O 2 and O 4 is successfully
implemented and it is proven, that the
combination with HICRU allow the retrieval of
at least one further cloud parameter (cloud top
height).
Outlook/Future work The radiation transfer
model TRACY will be used to retrieve modelled
air mass factors of O 2 and O 4 . These will be used
to retrieve a new database containing cloud top
height information.
Funding EVERGREEN (EU project)
Main publication Grzegorski et al. [2006]

62 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.4.4 Analysis of GOME Observations for Anthropogenic SO2 Emissions
over China
M. Fahim Khokhar
Abstract Fossil fuels such as coal and oil contain significant amounts of sulfur. When burned,
this sulfur is generally converted to SO2. GOME observations showed enhancements of SO2 column
amounts due to anthropogenic emission sources around the globe. These enhancements are identified
from the regions with extensive burning of coal and heavy industrial activities such as from China,
Eastern USA, the Arabian Peninsula, Eastern Europe and South Africa. A temporal increase during
the time period of 1996-2002 attributable to coal consumption in China is identified.
Figure 2.31: Time series of monthly mean SO2 SCD calculated from GOME observations for 1996-
2002 over Beijing and Shanghai. Fitted lines indicate the temporal increase in SO2 emissions of 15%
and 21% with winter maximum over Shanghai and Beijing respectively. Figure (adapted from [Zhou,
2001]) in nut shell shows the increase in fuel (coal) in china and black rectangle indicates the period
consistent to GOME observations.
Background satellite remote sensing is useful
tool to have information about various atmospheric
trace gas emissions and their distribution
on a global scale. Satellite instruments having
broader spectral range and better temporal resolution
(few days for global coverage) give us opportunity
to observe the whole globe with same
instrument and consequently help to discriminate
the spatial and temporal variations which make
them advantageous over other conventional instruments.
Methods and results GOME (Global Ozone
Monitoring Experiment, on-board ERS-2 since
1995) is a nadir-scanning UV-Vis. spectrometer
covering the wavelength range from 240 nm to 790
nm. From the ratio of earthshine radiance and
solar irradiance measurements, slant column densities
(SCD) of SO2 are derived by applying the
technique of differential optical absorption spec-
troscopy (DOAS). China’s rapid growth in industrial
activities unbalanced the growth and utilities
of electricity in China. Therefore, it exerts pressure
on coal mining in order to meet the electricity
demands and consequently leads to an increase
in environmental pollution. Figure in nut shell
indicates coal as a major source of fuel for thermal
power plants since 1990 and time series reflect
18% increase in the coal consumption by Chinese
power plants during the GOME time period of
1996-2002 (black box). Extensive use of coal in
China resulted in increase in SO2 emissions as obvious
from time series calculated over Shanghai
and Beijing region with temporal increase of 15%
and 21% respectively (see figure).
Funding PhD thesis (SCIA Validation).
Main Publication Khokhar [2006]

2.4. SATELLITE GROUP 63
2.4.5 Vertical OClO and BrO profiles from SCIAMACHY limb measurements
Sven Kühl
Abstract Vertcial profiles of BrO and OClO were retrieved from SCIAMACHY limb observations
and compared to ballon borne, groundbased and satellite measurements. The profiles are in accord
with expextations from stratopsheric chemistry and in quantitative agreement with the independent
measurements.
Figure 2.32: Left: BrO profiles derived from SCIAMACHY limb observations (black) in comparison
to correlative balloon measurements (red). Right: OClO number density at 18 km for the northern
hemisphere during selected days in January 2005 in comparison to the temperature and the ClO
mixing ratio measured by AURA-MLS at the 490 K Level ( 18km).
Background In the polar winter, temperatures
inside the polar vortex can drop below the threshold
for formation of polar stratospheric clouds
(PSCs) which is e.g. 195 K at an altitude of approx.
19 km. Heterogeneous reactions on PSCparticles
convert the ozone-inert chlorine reservoirs
(mainly ClONO2 and HCl) into ozone destroying
species (active chlorine, mainly Cl, ClO
and ClOOCl). This chlorine activation is the prerequisite
for massive ozone destruction by catalytic
cycles like the ClO-ClOOCl and the ClO-
BrO cycle after the return of sunlight in the polar
spring. Vertical profiles of BrO and OClO can
be derived from the SCIAMACHY observations
in the limb viewing geometry (i.e. tangential to
Earth and its atmosphere). Compared to measurements
of total columns the knowledge about
the vertical distribution allows to establish correlations
in a much more quantitative manner.
Methods and results For the retrieval of vertical
profiles from SCIAMACHY limb spectra we
apply a two step approach: First, SCDs of the
respective absorbers are derived by DOAS. In
the second step, box AMFs calculated by the
Monte Carlo RTM Tracy-II are applied to convert
the SCDs (as function of tangent height) to
vertical concentration profiles (number density as
function of altitude). First results on BrO and
OClO profiles were compared to independent measurements.
For OClO there exist no correlative
observations for SCIAMACHY validation so far.
Therefore, the OClO results are compared to ClO
measurements by AURA-MLS.
Outlook/Future work Improvment of retrieval,Investigating
OClO photochemistry by
combination of measurements in limb, nadir and
occultation geometry. Evaluation of the whole
SCIAMACHY data set for NO2, BrO and OClO
profiles. Monitoring of chlorine and bromine activation,
case studies (e.g. mountain wave-induced
chlorine activation)
Main publication Kühl et al. [2006a]

64 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.4.6 New GOME-Retrieval for Formaldehyde (HCHO) using daily mean
Earthshine Reference
Thierry Marbach
Abstract A new GOME-retrieval has been implemented for the trace gas formaldehyde (HCHO)
with daily mean earthshine as reference for the DOAS-fit. The cross-sections related to this new
retrieval are also calibrated against an earthshine spectra. The results (Figure 2.33) show a better
consistence of the data compare to the retrieval using the daily sun reference.
Figure 2.33: One day formaldehyde slant column density results (HCHO SCD) using the new GOMEretrieval
with daily mean earthshine reference and localization of the earthshine reference area (in
magenta).
Background The former GOME-retrieval used
a daily sun reference as well as sun-calibrated
cross sections for the DOAS-fit. The daily sun
reference is measured by the GOME instrument
once a day. This operation did not taken place
properly for some months. The alternative solution
was to use a fix sun reference instead of the
daily reference for the fit, but that induced offsets
in the results as well as many bad results. To
avoid these problems, we propose to calculate a
daily mean earthshine reference.
Methods and results The DOAS-fit has been
implemented for the evaluation of formaldehyde
(HCHO) in the spectral range 337-360 nm using
earthshine calibrated cross sections. The daily
sun reference has been replaced through a daily
earthshine reference. This reference is calculated
by doing the mean of the GOME measured pixels
situated in a 30 degree wide area over the Pacific
ocean (150W-180W; Figure 2.33). All calibrated
cross sections are linked to the daily mean earthshine
reference spectra for the DOAS fit.
One of the main improvement is the better
localization of the weaker sources (about
2.4x10 16 molec.cm −2 ) like over south-east China,
north India, east USA, and in general an improvement
for the higher latitudes (Figure 2.33). Some
of these weaker HCHO SCD (slant column density)
can also be detected over the oceans like over
the Gulf of Congo or over the coast of Peru. These
observations can be related to those made for the
Glyoxal results presented in this report by Steffen
Beirle (report 2.4.1) who also show over the same
bioactive oceanic regions enhanced Glyoxal levels,
possibly indicating VOC emissions over ocean.
The expected higher HCHO SCD over the evergreen
forests (Amazon basin, Indonesia) for this
season due to biomass burning and/or isoprene
emissions still clearly identify in the results (figure
2.33).
Outlook/Future work The next step is to implemente
a DOAS-fit using a daily mean earthshine
reference for the evaluation of HCHO
from the SCIAMACHY data and maybe also for
GOME-2. The DOAS fit can also be adapted for
other trace gases.
Funding The German Research Foundation
(DLR) is gratefully acknowledged for providing
the financial support.

2.4. SATELLITE GROUP 65
2.4.7 Radiative Transfer Modeling by Monte Carlo method for SCIA-
MACHY limb geometry in the UV/VIS spectral range
Janis Pukite
Abstract Number density profiles of O3, NO2, BrO and OClO can be obtained from SCIAMACHY
limb measurements in the UV-VIS spectral region: first, slant column densities of trace gas are
retrieved by DOAS from SCIAMACHY measurements at different elevation angles. Second, vertical
profiles are derived by inverting the SCDs. For that purpose radiative transfer modelling is necessary.
LOS elevation 39 km τ (340.25 nm)=0.23
LOS elevation 15 km τ (340.25 nm)=7.4
Figure 2.34: Illustration of scattering events (Rayleigh in red, ground in yellow) of photons contributing
to the measured signal in limb geometry at line of sight elevations of 39 and 15 km at tangent
point as calculated by ”Tracy-II”. Due to the large optical thickness for low elevation angles, the
contribution to measured light close to tangent point (TP) is small. Therefore 1) the sensitivity for
low altitudes (¡15 km) is low and 2) the measurements contain information about the atmosphere
between the region where scattering occurs and the instrument.
Background SCIAMACHY (Scanning Imaging
Absorption Spectrometer for Atmospheric
Chartography) on ENVISAT-1 measures solar
UV-VIS-NIR radiation transmitted, backscattered
and reflected by the atmosphere and the
ground. The limb-scanning mode is implemented
by the instrument allowing to perform measurements
at different elevation angles. From the measurements,
Slant column densities (SCDs) are retrieved.
The trace gas SCDs retrieved by DOAS
are indirect measurements of the profiles: they
contain information about their concentration at
different altitudes, related with the length of the
light path crossing these layers. This relation can
be described by a forward model. To connect the
measurements with spatial distribution of trace
gas concentrations in the atmosphere, radiative
transfer modelling needs to be applied.
Methods and results For the RTM the full
spherical Monte Carlo 3D model ”Tracy-II”, (sec-
TP
TP
tion 2.4.2) is used. The Monte Carlo method benefits
from conceptual simplicity and allows realizing
the spherical geometry of the atmosphere and
also its 3D properties. Moreover the model is assuming
every light path and scattering event (fig.
2.34) in terms of probability to take place. When
many light paths are calculated their statistics determine
radiative transfer properties of a model
atmosphere. This allows to calculate box air mass
factors necessary to invert the forward model and
to study the 3D sensitivity field of measurement.
Outlook/Future work A 2D retrieval will be
implemented for northern polar region and the
sensitivity field of measurement field will be studied.
Funding German national funding: Virtual institute
Tropische Tropopause’

66 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.4.8 Satellite observations of global water vapor trends 1996 - 2003
Thomas Wagner
Abstract From modern UV/vis satellite instruments, the integrated water vapor concentration
(often referred to as vertical column density or total column precipitable water) can be observed on
a global scale. In contrast to previous satellite observations in the infrared and microwave spectral
range our observations include both ocean and land surfaces with similar sensitivity.
Surface temperature trend 1996 – 2002 Trend of the H2O VCD 1996 – 2002
Figure 2.35: Global trend patterns of yearly averaged total column precipitable water and surface
temperature (from http://www.giss.nasa.gov/data/update/gistemp/). The trends of the total column
precipitable water are expressed as relative trends per year. Dark blue color indicates areas without
data.
Background Atmospheric water vapor is the
most important greenhouse gas contributing
about 2/3 of the natural greenhouse effect. In
contrast to other greenhouse gases like CO2 and
CH4 it has a much higher temporal and spatial
variability. The correct understanding and assessment
of atmospheric water vapor with respect to
the earths energy budget is further complicated
by its role in cloud formation and transport of
latent heat. Today, many details of how the hydrological
cycle reacts to climate change (water
vapor feedback) are still not understood. Especially
for the tropics, which contribute strongest
to the water vapor greenhouse effect, the strength
of the water vapor feedback is under intense debate.
In our studies we investigate the dependence
of the global distribution of water vapor
on surface temperature. Especially in the tropics
and the southern hemisphere many similarities
between the trend patterns of the total column
precipitable water and the temperature are
found. Over the northern hemispheric continents
also opposite trends occur.
Methods and results Our water vapor algorithm
is based on Differential Optical Absorp-
tion Spectroscopy (DOAS) performed in the wavelength
interval 611-673 nm. It consists of three
basic steps (described in detail in Wagner et al.
[2003]): in the first step, the spectral DOAS fitting
is carried out, taking into consideration cross
sections of O2 and O4 in addition to that of water
vapor. From the DOAS analysis, the water
vapor slant column density (the concentration integrated
along the light path) is derived. In the
second step, the water vapor slant column density
is corrected for the non-linearity arising from
the fact that the fine structure water vapor absorption
lines are not spectrally resolved by the
GOME instrument. In the last step, the corrected
water vapor slant column density is divided by a
’measured’ air mass factor which is derived from
the simultaneously retrieved O4 or O2 absorptions
[Wagner et al., 2006a].
Outlook/Future work The work will be continued
by applying the method to new satellite
instruments like SCIAMACHY and the GOME-
2-series. It can be expected that the time series
can be continued until 2020.
Main publication Wagner et al. [2006e]

2.4. SATELLITE GROUP 67
2.4.9 MAXDOAS observations on board the research vessel Polarstern
Thomas Wagner
Abstract MAX-DOAS measurements were carried on board the Polarstern from October 2005 to
present. Stratospheric and tropospheric trace gases are analysed including O3, NO2, HCHO, O4, and
BrO. During Austral winter 2006 the ship stayed in the area of first year sea ice for several weeks.
During this period almost continuously enhanced tropospheric BrO concentrations were measured.
Latitude [ ]
temperature [ C]
[W/m2]
[1014 molec/cm2]
-30
-40
-50
-60
-70
20
10
0
-10
-20
-30
1E+3
1E+2
1E+1
1E+0
15
10
5
0
a)
b)
c)
d)
Ice edge
temperature
water
air
Global radiation
Sun elevation
Ship
BrO DSCD 1° elevation
17-Jun 27-Jun 7-Jul 17-Jul 27-Jul 6-Aug 16-Aug
Time
Figure 2.36: Daily maximum BrO DSCDs for 1
degree elevation angle (d). Also shown are the
latitude of the ship and the ice edge (a), the temperatures
of air and water (b) as well as daily maximum
values of the global radiation and the sun
elevation (c). High BrO DSCDs are only found for
measurements within the area of first year sea ice
(indicated also by the water temperature < 0 0 C).
For low sun elevation (< −2.8 0 ) also no enhanced
BrO DSCDs were found.
Background The Multi AXis Differential Optical
Absorption Spectroscopy (MAX-DOAS) technique
allows to separate the absorptions taken
place at different altitudes in the atmosphere by
50
30
10
-10
Sun elevation [°]
observing scattered sun light from a variety of
viewing directions. This is possible because for
most measurement conditions, the observed light
is scattered in the free troposphere. Thus air
masses located close to the ground are traversed
on a slant absorption path determined by the
viewing direction; in contrast, stratospheric air
masses are traversed on a slant absorption path
determined by solar zenith angle. In addition to
the partial columns of various trace gases (like
NO2, BrO, HCHO, etc.) also information on the
aerosol profile can be retrieved.
Methods and results MAX-DOAS observations
were carried out during an extended ship
cruise from October 2005 to May 2007. MAX-
DOAS observations were continuously performed
using a mainly automated instrumentation. From
the MAX-DOAS observations latitudinal cross
sections of stratospheric O3 and NO2 were retrieved.
The O3 data were compared to satellite
observations from SCIAMACHY, and very good
agreement was achieved. During Austral winter
2006 enhanced tropospheric BrO concentrations
were observed for several weeks when the ship was
inside the belt of first year sae ice.
Outlook/Future work The data analysis will
be continued until the end of the cruise. It is foreseen
to install the MAX-DOAS as a permanent
instrument on board the Polarstern.
Funding The MAX-DOAS observations were
supported by the Alfred Wegener Institute in Bremerhaven.
Main publication Wagner et al. [2006c,d];
Frins et al. [2006]

68 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.4.10 Satellite monitoring of different vegetation types by differential optical
absorption spectroscopy (DOAS) in the red spectral range
Thomas Wagner
Abstract A new method for the satellite remote sensing of different types of vegetation and ocean
colour is presented, which is based weak narrow-band (few nm) spectral reflectance structures (i.e.
’fingerprint’ structures) of vegetation in the red spectral range. The global maps of the results illustrate
the seasonal cycles of different vegetation types.
Figure 2.37: Global monthly mean results of the DOAS retrieved fitting coefficients for (the logarithms
of the) different vegetation spectra (top: conifers, centre: deciduous, bottom: grass). The results for
deciduous trees and grass are very similar; those for conifers show different spatial patterns. The effect
of the seasonal cycle is clearly visible.
Background Vegetation has a strong influence
on the cycles of trace gases and other important
properties of the earth system, in particular the
earth’s energy budget. Vegetation modifies the
ground albedo and thus has a strong impact on the
amount of backscattered solar energy. Vegetation
also strongly influences the water cycle through
its influence on evaporation; the release of latent
heat is important for the latitudinal energy distribution.
Plants are also sources and/or sinks for
many important trace gases, in particular greenhouse
gases. Therefore, the precise knowledge
of the spatio-temporal variation of the biological
activity is an important prerequisite for the correct
understanding and simulation of global trace
gas budgets and of the earth’s climate. Of special
importance is the monitoring of the humaninduced
change of the global vegetation patterns,
e.g. caused by biomass burning or climate change.
Methods and results Our vegetation algorithm
is based on Differential Optical Absorp-
tion Spectroscopy (DOAS) performed in the wavelength
interval 605-673 nm. In contrast to existing
algorithms relying on the strong change of the
reflectivity in the red and near infrared spectral
region, our method analyses weak narrow-band
(few nm) reflectance structures (i.e. ’fingerprint’
structures) of vegetation in the red spectral range.
Since the spectra of atmospheric absorption and
vegetation reflectance are simultaneously included
in the analysis, the effects of atmospheric absorptions
are automatically corrected (in contrast to
other algorithms). The inclusion of the vegetation
spectra also significantly improves the results
of the trace gas retrieval.
Outlook/Future work The work will be continued
by applying the method to new satellite
instruments like SCIAMACHY and the GOME-
2-series. It can be expected that the time series
can be continued until 2020.
Main publication Wagner et al. [2006e,j]

2.4. SATELLITE GROUP 69
References
Beirle, S., Volkamer, R., Wittrock, F., Richter, A., Burrows, J., Platt, U., & Wagner, T. 2006a.
DOAS RETRIEVAL OF GLYOXAL FROM SPACE. Proceedings of the ESA Atmospheric Science
Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy.
Beirle, S., Spichtinger, N., Stohl, A., Cummins, K. L., Turner, T., Boccippio, D., Cooper, O. R., Wenig,
M., Grzegorski, M., Platt, U., & Wagner, T. 2006b. ESTIMATING THE NOx PRODUCED BY
LIGHTNING FROM GOME AND NLDN DATA: A CASE STUDY IN THE GULF OF MEXICO.
Atmos. Chem. Phys., 6, 10751089.
Bergamaschi, P., Frankenberg, C., Meirink, J. F., Kroll, M., Dentener, F., Wagner, T., Platt, U., Kaplan,
J. O., Körner, S., Heimann, M., Dlugokencky, E. J., & Goede, A. 2006. SATELLITE CHAR-
TOGRAPHY OF ATMOSPHERIC METHANE FROM SCIAMACHY ONBOARD ENVISAT: (II)
EVALUATION BASED ON INVERSE MODEL SIMULATIONS. J. Geophys. Res., accepted.
Bruns, M., Buehler, S. A., Burrows, J. P., Richter, A., Rozanov, A., Wang, P., Heue, K.-P., Platt, U.,
Pundt, I., & Wagner, T. 2006. NO2 PROFILE RETRIEVAL USING AIRBORNE MULTI AXIS
UV-VISIBLE SKYLIGHT ABSORPTION MEASUREMENTS OVER CENTRAL EUROPE. Atmos.
Chem. Phys., 6, 3049–3058.
Butz, A., Bösch, H., Camy-Peyret, C., Chipperfield, M., Dorf, M., Dufour, G., Grunow, K., Jeseck,
P., Kühl, S., Payan, S., Pepin, I., Pukite, J., Rozanov, A., von Savigny, C., Sioris, C., Wagner,
T., Weidner, F., & Pfeilsticker, K. 2006. INTER-COMPARISON OF STRATOSPHERIC O3 AND
NO2 ABUNDANCES RETRIEVED FROM BALLOON BORNE DIRECT SUN OBSERVATIONS
AND ENVISAT/SCIAMACHY LIMB MEASUREMENTS. Atmos. Chem. Phys., 6, 1293–1314.
Deutschmann, T., & Wagner, T. 2006. TRACY-II Users Manual.
Dils, B., De Maziere, M., Blumenstock, T., Buchwitz, M., de Beek, R., Demoulin, P., Duchatelet, P.,
Fast, H., Frankenberg, C., Gloudemans, A., Griffith, D., Jones, N., Kerzenmacher, T., Kramer, I.,
Mahieu, E., Mellqvist, J., Mittermeier, R. L., Notholt, J., Rinsland, C. P., Schrijver, H., Smale,
D., Strandberg, A., Straume, A. G., Stremme, W., Strong, K., Sussmann, R., Taylor, J., van den
Broek, M., Wagner, T., Warneke, T., Wiacek, A., & Wood, S. 2006. COMPARISONS BETWEEN
SCIAMACHY AND GROUND-BASED FTIR DATA FOR TOTAL COLUMNS OF CO, CH4, CO2
AND N2O. Atmos. Chem. Phys., 6, 1953–1976.
Frankenberg, C., Meirink, J. F., Bergamaschi, P., Goede, A., Heiman, M., Körner, S., Platt, U., van
Weele, M., & Wagner, T. 2006. SATELLITE CHARTOGRAPHY OF ATMOSPHERIC METHANE
FROM SCIAMACHY ON BOARD ENVISAT: ANALYSIS OF THE YEARS 2003 AND 2004. J.
Geophys. Res., 111, D07303, doi:10.1029/2005JD006235.
Frie, F., Monks, P. S., Remedios, J. J., Rozanov, A., Sinreich, R., Wagner, T., & Platt, U. 2006.
MAX-DOAS O4 MEASUREMENTS: A NEW TECHNIQUE TO DERIVE INFORMATION ON
ATMOSPHERIC AEROSOLS. (II) MODELLING STUDIES. J. Geophys. Res., 111, D14203,
doi:10.1029/2005JD006618.
Frins, E., Bobrowski, N., Platt, U., & Wagner, T. 2006. TOMOGRAPHIC MAX-DOAS OBSERVA-
TIONS OF SUN ILLUMINATED TARGETS: A NEW TECHNIQUE PROVIDING WELL DE-
FINED ABSORPTION PATHS IN THE BOUNDARY LAYER. Applied Optics, 45, 6227–6240.
Grzegorski, M., Wenig, M., Platt, U., Stammes, P., Fournier, N., & Wagner, T. 2006. THE HEIDEL-
BERG ITERATIVE CLOUD RETRIEVAL UTILITIES (HICRU) AND ITS APPLICATION TO
GOME DATA. Atmos. Chem. Phys., 6, 4461–4476.
Hendrick, F., Van Roozendael, M., De Maziere, M., Richter, A., Rozanov, A., Sioris, C., Dorf, M.,
Kühl, S., Pukite, J., Wagner, T., & Goutail, F. 2006. BrO PROFILING FROM GROUND-BASED
DOAS OBSERVATIONS: NEW TOOL FOR THE ENVISAT/SCIAMACHY VALIDATION. proceedings
of the ESA Atmospheric Science Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy.
Khokhar, M. F. 2006. RETRIEVAL AND INTERPRETATION OF TROPOSPHERIC SO2 FROM
UV-VIS SATELLITE INSTRUMENTS. PhD Thesis, University of Leipzig.
Kühl, S., Pukite, J., Deutschmann, T., Platt, U., & Wagner, T. 2006a. SCIAMACHY Limb Measurements
of NO2, BrO and OClO. Retrieval of vertical profiles: Algorithm, first results and validation.
Adv. Space Res., in review.

70 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
Kühl, S., Pukite, J., Deutschmann, T., Dorf, M., Hendrick, F., Platt, U., & Wagner, T. 2006b.
STRATOSPHERIC OClO AND BrO PROFILES FROM SCIAMACHY LIMB MEASUREMENTS.
Proceedings of the ACVE-3 Workshop, 4 7 December, Frascati, Italy, 2006.
Loyola, D., Valks, P., Ruppert, T., Richter, A., Wagner, T., van der A, R., & Meisner, R. 2006.
THE 1997 EL NIÑO IMPACT ON CLOUDS, WATER VAPOUR, AEROSOLS AND REACTIVE
TRACE GASES IN THE TROPOSPHERE, AS MEASURED BY THE GLOBAL OZONE MON-
ITORING EXPERIMENT. Advances in Geosciences, 6, 267 272.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006a. IDENTIFICATION OF HCHO SOURCES
DUE TO ISOPRENE OR/AND BIOMASS BURNING EMISSIONS USING COMBINED HCHO
AND NO2 SATELLITE OBSERVATIONS. 36th COSPAR Scientific Assembly Abstracts, A1.1-
0063.06.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006b. ISOPRENE AND BIOMASS BURNING
EMISSIONS FROM SATELLITE OBSERVATIONS: SYNERGISTIC USE OF HCHO AND NO2
TRACE GAS MEASUREMENTS. ESA Atmospheric Science Conference abstract book.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006c. ISOPRENE AND BIOMASS BURNING
EMISSIONS FROM SATELLITE OBSERVATIONS: SYNERGISTIC USE OF HCHO AND NO2
TRACE GAS MEASUREMENTS. Geophysical Research Abstracts, 8, 07665.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006d. ISOPRENE AND BIOMASS BURNING
EMISSIONS FROM SATELLITE OBSERVATIONS: SYNERGISTIC USE OF HCHO AND NO2
TRACE GAS MEASUREMENTS. 3rd International DOAS Workshop abs. Vol.
Pukite, J., Kühl, S., Deutschmann, T., Wilms-Grabe, W., Platt, U., & Wagner, T. 2006a. LIMB
RETRIEVAL OF STRATOSPHERIC TRACE GASES FROM SCIAMACHY USING MONTE
CARLO RADIATIVE TRANSFER MODELING. 3rd International DOAS Workshop abs. Vol.
Pukite, J., Kühl, S., Deutschmann, T., Wilms-Grabe, W., Friedeburg, C., Platt, U., & Wagner,
T. 2006b. RETRIEVAL OF STRATOSPHERIC TRACE GASES FROM SCIAMACHY LIMB
MEASUREMENTS. Proceedings of the ESA Atmospheric Science Conference, 8-12 May 2006,
ESA ESRIN, Frascati, Italy.
Pukite, J., Kühl, S., Deutschmann, T., Wilms-Grabe, W., Friedeburg, C., Platt, U., & Wagner,
T. 2006c. RETRIEVAL OF STRATOSPHERIC TRACE GASES FROM SCIAMACHY LIMB
MEASUREMENTS. Geophysical Research Abstracts, 8, 08102.
Sinreich, R., Volkamer, R., Filsinger, F., Frie, U., Kern, C., Platt, U., Sebastian, O., & Wagner, T.
2006. MAX-DOAS DETECTION OF GLYOXAL DURING ICARTT 2004. Atmos. Chem. Phys.
Discuss., 6, 9459–9481.
Toenges-Schuller, N., Stein, O., Rohrer, F., Wahner, A., Richter, A., Burrows, J. P., Beirle, S.,
Wagner, T., Platt, U., & Elvidge, C. D. 2006. GLOBAL DISTRIBUTION PATTERN OF AN-
THROPOGENIC NITROGEN OXIDE EMISSIONS: CORRELATION ANALYSIS OF SATEL-
LITE MEASUREMENTS AND MODEL CALCULATIONS. J. Geophys. Res., 111, D05312,
doi:10.1029/2005JD006068.
Wagner, T., Beirle, S., Deutschmann, T., Frankenberg, C., Grzegorski, M., Hollwedel, J., Khokhar,
M. F., Kühl, S., Marbach, T., Platt, U., Pukite, J., Sanghavi, S., & Wilms-Grabe, W. 2006a. 10
YEARS OF REMOTE SENSING WITH MODERN UV/VIS/NIR SATELLITE INSTRUMENTS:
A NEW VIEW ON GLOBAL NEAR-SURFACE TRACE GAS DISTRIBUTIONS. presentation at
the 36TH COSPAR SCIENTIFIC ASSEMBLY BEIJING, CHINA, 16 23 JULY 2006.
Wagner, T., Beirle, S., Grzegorski, M., & Platt, U. 2006b. CHARACTERIZATION OF VEGETA-
TION TYPE USING DOAS SATELLITE RETRIEVALS. poster presentation at the ESA Atmospheric
Science Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy.
Wagner, T., Burrows, J. P., Deutschmann, T., Dix, B., Hendrick, F., v.Friedeburg, C., Frie, U., Heue,
K.-P., Irie, H., Iwabuchi, H., Kanaya, Y., Keller, J., McLinden, C. A., Oetjen, H., Palazzi, E.,
Petritoli, A., Platt, U., Postylyakov, O., Pukite, J., Richter, A., van Roozendael, M., Rozanov,
A., Rozanov, V., Sinreich, R., Sanghavi, S., & F., Wittrock. 2006c. COMPARISON OF BOX-
AIR-MASS-FACTORS AND RADIANCES FOR MULTIPLE-AXIS DIFFERENTIAL OPTICAL

2.4. SATELLITE GROUP 71
ABSORPTION SPECTROSCOPY (MAX-DOAS) GEOMETRIES CALCULATED FROM DIF-
FERENT UV/VISIBLE RADIATIVE TRANSFER MODELS. J. Atmos. Chem. Phys. Discuss.,
6, 9823–9876.
Wagner, T., Ibrahim, O., Sinreich, R., Frie, U., & Platt. 2006d. ENHANCED TROPOSPHERIC BRO
CONCENTRATIONS OVER THE ANTARCTIC SEA ICE BELT IN MID WINTER OBSERVED
FROM MAX-DOAS OBSERVATIONS ON BOARD THE RESEARCH VESSEL POLARSTERN.
Atmos. Phys. Chem., submitted.
Wagner, T., Beirle, S., Grzegorski, M., & Platt. 2006e. GLOBAL TRENDS (1996 TO 2003)
OF TOTAL COLUMN PRECIPITABLE WATER OBSERVED BY GOME ON ERS-2 AND
THEIR RELATION TO SURFACE TEMPERATURE. J. Geophys. Res., 111, D12102,
doi:10.1029/2005JD006523.
Wagner, T., Beirle, S., Grzegorski, M., & Platt, U. 2006f. GLOBAL TRENDS OF CLOUD COVER
AND CLOUD HEIGHT DERIVED FROM GOME SATELLITE OBSERVATIONS 1996-2003 AND
THEIR RELATION TO SURFACE-NEAR TEMPERATURE. poster presentation at the 2006 Fall
Meeting: 1115 December 2006, San Francisco, California.
Wagner, T., Beirle, S., Grzegorski, M., & Platt, U. 2006g. INVESTIGATING THE EARTH’S HY-
DROLOGICAL CYCLE USING H2O VCDS AND CLOUD RELATED PARAMETERS FROM
GOME-II. Proceedings of the 1st EPS/MetOp RAO Workshop ESRIN, Frascati, Italy, 15-17 May
2006.
Wagner, T., Beirle, S., Deutschmann, T., Grzegorski, M., Sanghavi, S., & Platt, U. 2006h. PROBING
INTERNAL CLOUD PROPERTIES FROM SPACE. presentation at the ESA Atmospheric Science
Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy.
Wagner, T., Beirle, S., Deutschmann, T., Grzegorski, M., Sanghavi, S., & Platt, U. 2006i. PROB-
ING INTERNAL CLOUD PROPERTIES FROM SPACE. presentation at the 36TH COSPAR
SCIENTIFIC ASSEMBLY BEIJING, CHINA, 16 23 JULY 2006.
Wagner, T., Beirle, S., Deutschmann, T., Grzegorski, M., & Platt. 2006j. SATELLITE MONITOR-
ING OF DIFFERENT VEGETATION TYPES BY DIFFERENTIAL OPTICAL ABSORPTION
SPECTROSCOPY (DOAS) IN THE RED SPECTRAL RANGE. Atmos. Chem. Phys., accepted.
Wang, P., Richter, A., Bruns, M., Burrows, J. P., Junkermann, W., Heue, K.-P., Wagner, T., Platt, U.,
& Pundt, I. 2006. AIRBORNE MULTI-AXIS DOAS MEASUREMENTS OF TROPOSPHERIC
SO2 PLUMES IN THE PO-VALLEY, ITALY. Atmos. Chem. Phys., 6, 329338.
Wittrock, F., Richter, A., Oetjen, H., Burrows, J. P., Kanakidou, M., Myriokefalitakis, S., Volkamer,
R., Beirle, S., Platt, U., & Wagner, T. 2006. Simultaneous global observations of glyoxal and
formaldehyde from space. Geophys. Res. Lett., 33, doi:10.1029/2006GL026310.

2.5. MARHAL - MODELING OF MARINE AND HALOGEN CHEMISTRY 73
2.5 MarHal - Modeling of marine and halogen chemistry
MarHal is an independent Junior Research Group that is funded by the Deutsche Forschungsgemeinschaft
within the Emmy-Noether program. The main research foci of our group are the investigation
of photochemical and microphysical processes in the troposphere, especially in the marine boundary
layer using numerical models.
Group members
Dr. Roland von Glasow, head of group
Dr. Susanne Pechtl (b. Marquart), PostDoc, until 30.11.2006
Matthias Piot, DEA in oceanography and meteorology, PhD student
Dipl. Met. Linda Smoydzin, PhD student
Thomas Kaschka, diploma student
Scientific objectives
Figure 2.38: Overview of the research topics of MarHal.
Our main research topics are tropospheric photochemistry and chemistry-cloud-climate interactions.
Specifically, we are studying the impact of halogen chemistry on ozone photochemical destruction
(e.g. by catalytic reaction cycles of halogen oxides) and production (i.e. by changing the
OH/HO2 and NO/NO2 ratios) in the polar boundary layer, the remote and coastal marine boundary
layer (MBL), over salt lakes, and in the free troposphere. Our interest in chemistry-cloud-climate
interactions focuses on new particle formation in the MBL involving iodine oxides and the sulfur cycle
in the MBL and the relevance of halogen gas and aqueous phase reactions with dimethyl sulfide and
its reaction products and the impact of sea salt aerosol particles on the sulfur cycle.
Background
Seventy percent of the Earth’s surface is covered by oceans. Particles and gases are released from
the ocean and have an influence on atmospheric chemistry and climate via changes of the oxidation
power of the atmosphere. Furthermore, feedbacks between chemistry and, for example, cloud microphysical
properties occur, that change the albedo and therefore alter the energy budget of the Earth
(e.g. sulfate and sea salt aerosol particles and their role as cloud condensation nuclei). Measurements

74 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
in the marine troposphere and in seawater have shown that exchanges of climatically relevant gases
like dimethyl sulfide (DMS) and non-methane hydrocarbons occur which can have a significant impact
on regional and even global photochemistry and climate. Furthermore, sea salt aerosol particles
are produced that contain chlorine and bromine. Numerous aerosol samples have shown that marine
aerosol is depleted in bromine compared to sea water. Once released to the gas phase bromine participates
in ozone destruction cycles and also oxidizes dimethyl sulfide (DMS). Iodine is being released via
biological processes in dramatic amounts from several coastal regions but also from the open ocean.
Iodine is very efficient in destroying ozone and if concentrations of iodine oxides are high enough, new
particle formation can occur.
The role of halogens in tropospheric chemistry is not restricted to the marine environment. Very
high mixing ratios of the radical bromine oxide have been measured during strong surface Ozone
Depletion Events in polar regions in springtime and over salt lakes. In the Arctic BrO has also been
implicated in so-called Mercury Depletion Events with an increase in the deposition of bio-available,
toxic mercury. Various measurements indicate that there is a significant background of the bromine
oxide radical in the troposphere, most likely in the free troposphere, which would significantly impact
the background photochemistry in this sensitive environment [see von Glasow et al. , 2004]. An
overview of tropospheric halogen chemistry can be found in von Glasow & Crutzen [2006].
Although the mentioned “halogen domains” appear to be very different they have striking similarities
when halogen release and cycling are considered. This makes it feasible to address the associated
research questions in one research group to benefit from synergies. Figure 2.38 shows schematically
our research topics, making the interconnections more obvious.
Main methods
Our research tools are numerical models. The main model is the one-dimensional model of the
marine boundary layer MISTRA [von Glasow et al. , 2002a,b; von Glasow & Crutzen, 2004] that treats
chemical processes in the gas phase, in and on aerosol particles, and cloud droplets. The microphysical
module includes the growth of particles due to water vapor and uptake of other gases and a two-way
feedback with radiation. Aqueous phase chemistry is calculated in sulfate and sea salt aerosol and -
if a cloud is present - in cloud droplets that grew on each type of aerosol. The chemical mechanism
comprises about 170 reactions in the gas phase and 270 reactions in and on aqueous particles for
each of the four chemical bins. For some applications the model is run in box model mode where the
relevant meteorological parameters (temperature, relative humidity, particle radius and liquid water
content) are adjusted to the problem under investigation.
We are developing an improved microphysical/microchemical module that will allow us to make
more detailed studies of the microphysical (mainly growth) and chemical interactions of a particle
population.
Furthermore we have been using the global three-dimensional model MATCH-MPIC [von Glasow
et al. , 2004; Schofield et al. , 2006] for a first global assessment of tropospheric halogen chemistry.
Main recent activities
All group members actively take part in model development and application. Below we briefly
outline the single projects which are explained in more detail in the following sections.
Polar halogen chemistry is being investigated by Matthias Piot (see 2.5.2) focusing on the effects
of various chemical and meteorological parameters for the development of ozone depletion events. The
effects of organic surfactants on sea salt aerosol on particle growth and chemical processes like uptake
or scavenging of gas phase compounds is the subject of Linda Smoydzin’s work (see 2.5.3). Susanne
Pechtl (b. Marquart) has developed and applied a parameterization for the nucleation of new aerosol
particle from iodine vapors [Pechtl et al. , 2006b] and key modules for our improved microphysical
module. Another focus was the continuation of her work on iodine chemistry, esp. aqueous phase
reactions (see 2.5.1). Effects of surface reactions on sea salt aerosol had been proposed in the literature
to be of potentially great importance for the marine sulfur cycle, our model results showed, however,
that the effects had been overestimated and are unlikely to be of importance (see 2.5.4). We continued
our investigation of chemical processes in volcanic plumes in collaboration with Italian colleagues. One
focus was sulfur chemistry in volcanic plumes [Aiuppa et al. , 2006]. Furthermore, Thomas Kaschka
is developing an explicit model of the very-early plume chemical processes. We also contributed to
the Scientific Assessment of Stratospheric Ozone by the World Meteorological Organization [WMO,
2006].

2.5. MARHAL - MODELING OF MARINE AND HALOGEN CHEMISTRY 75
Funding
Deutsche Forschungsgemeinschaft, Emmy-Noether Junior Research Group MarHal GL 353/1-2
Cooperation within the institute and with groups outside of the institute
Tropospheric research group, IUP Heidelberg
Alfred-Wegener-Institut, Bremerhaven
Cape Grim Baseline Air Pollution Station, Tasmania, Australia
Dipartimento CFTA, Università di Palermo, Italy
INGV - Sezione di Palermo, Palermo, Italy
Max-Planck-Institut für Chemie, Mainz (MPI-C)
National Institute of Water and Atmospheric Research (NIWA), New Zealand
National Oceanic and Atmospheric Administration, NOAA, Boulder, USA
Scripps Inst. of Ocanography, University of California, San Diego (SIO), USA
Universität Bremen
Universitée Libre de Bruxelles, Belgium
University of California, Los Angeles (UCLA), USA
University of New Hampshire, USA
University of Virginia, USA
Peer Reviewed Publications
1. Bobrowski et al. [2006]
2. Keene et al. [2006]
3. Meyer et al. [2006]
4. Pechtl et al. [2006b]
5. Ponater et al. [2006]
6. Schofield et al. [2006]
7. von Glasow [2006b]
8. von Glasow & Crutzen [2006]
9. WMO [2006]
Papers in online review
1. Aiuppa et al. [2006]
2. Pechtl et al. [2006a]
3. Smoydzin & von Glasow [2006]
Invited talk
1. von Glasow [2006a]

76 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.5.1 Modeling iodide – iodate speciation in atmospheric aerosol
Susanne Pechtl, Guy Schmitz (Faculté des Sciences Appliquées, Universitée Libre de Bruxelles,
Belgium), Roland von Glasow
Abstract The speciation of iodine in atmospheric aerosol is currently poorly understood. Models
predict negligible iodide concentrations, but accumulation of iodate in aerosol, both of which is not
confirmed by recent measurements. An updated aqueous phase iodine chemistry scheme for use in
atmospheric models was developed, which improves the agreement with measurements significantly.
HIO 3
IO
ICl 2 -
IClBr -
ICl
HOCl
HOBr
HOI
Cl -
H + Br -
H +
IBr 2 -
HI
HIO 2
IBr
I -
H +
H2O2 HOCl HOBr
H +
HIO2 H +
HSO 3 -
DOM?
HOCl
SO 3 -
I 2
HOBr
H +
O 3
H
HOI
+ IBr
ICl
H +
IO 3 -
HSO 3 -
I -
aerosol
gas phase
Figure 2.39: Scheme of aqueous phase iodine chemistry as implemented in the marine boundary layer
model MISTRA. Additional reactions compared to earlier schemes are highlighted in red.
Background Although during recent years
progress has been made regarding atmospheric
iodine chemistry, several aspects are still poorly
understood, one of which is the speciation of iodine
in atmospheric aerosol. Current models of
atmospheric chemistry predict that the aerosol iodide
(I− ) concentration is negligible, while iodate
(IO − 3
) is believed to be inert and thus accumulate
in particles. In contrast, observational data provide
evidence for a non-negligible iodide content in
aerosol samples. During two extended ship cruises
in the Atlantic Ocean, highly variable I − /IO − 3 ratios
were found.
Methods and results An updated aqueous
phase iodine chemistry scheme (Figure 2.39) was
developed for the marine boundary layer model
MISTRA, which includes chemistry in the gas
and aerosol phase as well as aerosol microphysics.
Model sensitivity studies show that iodate can be
reduced in acidic aerosol by inorganic reactions,
i.e., iodate does not necessarily accumulate in particles.
Furthermore, the transformation of particulate
iodide to volatile iodine species likely has
been overestimated in previous model studies due
to negligence of collision-induced upper limits for
the reaction rates. However, inorganic reaction
cycles still do not seem to be sufficient to reproduce
the observed range of iodide-iodate speciation.
Therefore, the effects of the recently suggested
reaction of HOI with dissolved organic matter
(DOM) to produce I − was also investigated. If
this reaction is fast enough to compete with the
inorganic mechanism, it would not only directly
lead to enhanced iodide concentrations but, indirectly
via speed-up of iodate reduction cycles,
also to a decrease in iodate. Hence, organic iodine
chemistry combined with inorganic reaction
cycles seems to be able to reproduce observations.
The presented chemistry is highly dependent on
pH and thus offers an explanation for the large
observed variability of the iodide-iodate speciation
in atmospheric aerosol.
Outlook/Future work The existence of organic
forms of iodine has to be re-confirmed in
further measurements and its consequences for iodine
speciation has to be investigated.
Funding DFG: Emmy Noether Junior Research
Group MarHal GL 353/1-2
Main publication Pechtl et al. [2006a]

2.5. MARHAL - MODELING OF MARINE AND HALOGEN CHEMISTRY 77
2.5.2 The Potential Importance of Frost Flowers for Ozone Depletion Events
- A Model Study
Matthias Piot, Roland von Glasow
Abstract For more than 20 years, events with almost complete loss of ozone have been observed
in the Arctic in spring. We performed model studies with the one-dimensional model MISTRA to
investigate the potential role of frost flowers (FF) in this depletion of tropospheric ozone.
Figure 2.40: Left: Schematic depiction of the most important processes included in the Arctic version
of MISTRA. The boundary layer is denoted as BL, open lead as OL, and the free troposphere as FT.
Aerosol and gas phase chemistry are calculated in all layers. (1): Deposition process; (2): Br2/BrCl
re-emission from the snowpack. Right: typical gas phase O3 during an ODE in the BL.
Background Reactive halogens play a major
role in polar ozone depletion events (ODE): the
reaction of bromine atoms with ozone, followed
by the self-reaction of bromine oxides (BrO) represents
a catalytic loss mechanism for ozone in the
polar boundary layer (PBL). However, the triggering
of the so-called ”bromine explosion” remains
unclear. We present a sensitivity study where meteorological
as well as chemical parameters are
assessed. This study helps us better understand
the conditions favorable for the development of an
Ozone Depletion Event (ODE).
Methods and results We used MISTRA in
a “Lagrangian mode” where a model column of
2000 m height moves across a pre-defined sequence
of surfaces: snow, FF, and open lead (see
Fig. 2.40-left), with FF aerosols being produced
during the FF section. We show that a major
ozone depletion event can be satisfactorily reproduced
if the recycling on snow of deposited halogens
into gas phase Br2/BrCl is considered (see
ozone mixing ratio in Fig. 2.40-right). This cycling
maintains sufficiently high levels of bromine
to deplete ozone down to few nmol mol −1 within
four days. We also assessed the influence of different
combinations of open lead/frost flowers on the
chemistry of the moving column. Results showed
noticeable modifications affecting the composition
of aerosols and the deposition velocities due to
variation of the humidity in the air. In addition,
we studied the effects of modified temperature of
either the frost flower field or the ambient airmass.
A warmer FF field increases the relative
humidity and the aerosol deposition rate. The
deposition/re-emission process is larger, inducing
more reactive bromine in the gas phase, and a
stronger ozone depletion. A decrease of 1 K in
airmass temperature shows that the aerosol uptake
capacity substantially increases, leading to
enhanced uptake of acids from the gas phase: the
bromine explosion accelerates and O3 mixing ratios
decreases. Recent studies have suggested the
important role of the precipitation of calcium carbonate
(CaCO3) out of the brine layer for the
possible acidification of the liquid phase by acid
uptake. Our investigation showed that this precipitation
is a crucial process for the timing of
the bromine explosion in aerosols. Finally, we investigated
the release of Br2 potentially produced
by heterogeneous reactions directly on frost flowers.
In this case, we obtained unlikely results for
aerosol compositions and deposition rates on snow
compared to observations made in the Arctic.
Funding DFG-Emmy Noether Junior Research
group Marhal GL 353/1-2.

78 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.5.3 Modeling organic surface films on Atmospheric Aerosol Particles and
their Influence on Chemistry
Linda Smoydzin, Roland von Glasow
Abstract Organic material from the ocean’s surface can be incorporated into sea salt aerosol particles
often producing a surface film on the aerosol. Such an organic coating can reduce the mass
transfer between the gas phase and the aerosol phase influencing sea salt chemistry in the marine
atmosphere.
Figure 2.41: Time evolution of total bromine and chlorine gas phase mixing ratios and HOBr and
HOCl aqueous phase concentrations at 50 m altitude for three days (midnight day 1 - midnight day 3).
The different lines refer to different cases where the fractions of the organic constituents which react
with ozone and OH are varied. The accommodation coefficient is reduced by one order of magnitude
for all cases. Red: 50% OA, 50% ORG, green: 47% OA 52% ORG, blue: 45% OA, 55% ORG, black:
base case without organic coatings.
Background Recent field measurements have
shown that the organic mass fraction in marine
particles can be up to 60% especially in regions
with high biological activity. However, it is not
possible to determine which organic species are
present on sea salt aerosols.
Methods and results To investigate the importance
of surfactants for atmospheric chemistry
in the marine boundary layer (MBL) the onedimensional
numerical model MISTRA is used.
Uncertainties regarding the magnitude of uptake
reduction, the concentrations of organic compounds
in sea salt aerosols and the oxidation rate
of the organics are considered to analyse the possible
influence of organic surfactants on gas and
liquid phase chemistry.
Organic surface films can be destroyed by reaction
with atmospheric oxidants like ozone or OH.
As long as a complete coating on the sea salt particle
is present the accommodation coefficient is
reduced. By assuming destruction rates for the organic
coating (which comprises of oleic acid (OA))
based on laboratory measurements we saw a rapid
destruction of the organic coatings within the first
meters of the MBL. Larger organic initial concentrations
lead to a longer lifetime of the coating
but lead also to an unrealistically strong decrease
of ozone concentrations as the organic film
is destroyed by reaction with ozone. The lifetime
of the film can be increased by either assuming
smaller reactive uptake coefficients for ozone on
oleic acid or by assuming that a part of the organic
surfactants (ORG) react with OH. By variing
the oleic acid/ORG fraction sensitivity studies
were perfomed. It can be shown that gas phase
halogen concentrations decrease. Chlorine concentrations
decrease stronger than Bromine concentrations
(∆Cl(tot):10-20%, ∆Br(tot):9%). For
the aqueous phase we see an increase in bromine
(∆HOBr:30%) and a decrease in chlorine concentrations
(∆HOCl:40-50%). Overall aqueous phase
chemistry is affected stronger than gas phase
chemistry.
Funding DFG-Emmy Noether Junior Research
group Marhal GL 353/1-2
Main publication Smoydzin & von Glasow
[2006]

2.5. MARHAL - MODELING OF MARINE AND HALOGEN CHEMISTRY 79
2.5.4 Importance of the surface reaction OH + Cl − on sea salt aerosol for
the chemistry of the marine boundary layer - a model study
Roland von Glasow
Abstract The implications for the chemistry of the marine boundary layer (MBL) of the reaction
of OH with Cl − on the surface of sea salt aerosol producing gas phase Cl2 and particulate OH − have
been investigated with a numerical model. They were found to be very minor in contradiction to
previous suggestions in the literature.
Figure 2.42: Temporal evolution of the most important gas phase compounds for scenario “remote
MBL”. The difference between the “cases” is how the reaction rate of the surface reaction is calculated
as explained in paranthesis. Case 1 (no surface reaction) - black, solid line; case 2 (“best guess”) -
red, dashed line; case 3 (no gas phase diffusion limitation) - blue, dotted line; case 4 (γ = 1, with
gas phase diffusion limitation) - blue, solid line; case 5 (γ = 1, no gas phase diffusion limitation) -
green, dash-dotted line. Note, that most lines except for Cl2 and Cl overlap. The abscissa is time
since model start in minutes.
Background The reaction OH + Cl − −→
OH − + Cl2 had been suggested by Laskin et
al. (2003) to play a major role in the sulfur
cycle in the marine boundary layer. The aqueous
phase oxidation of SO2 is strongly pH dependent,
and relevant mainly in fresh, non-acidified
sea salt aerosol particles. This pathway for sulfur
oxidation would gain in importance if alkalinity
would be produced in the particles as is the case
in the aforementioned reaction. Furthermore, it
was suggested that the gas phase product, Cl2,
might be relevant for the photochemistry of the
MBL.
Methods and results Based on literature data
a new “best estimate” for the rate coefficient of the
surface reaction was deduced and applied in the
box-model vesrion of MISTRA. Its importance for
the chemistry of the MBL has been investigated
under conditions typical for the pristine MBL of
the Southern Ocean, the remote MBL, and marine
regions influenced by polluted outflow from
the continent.
The results showed that the additional sulfate
production by this reaction is less than 1%, therefore
having only a minor impact on sulfate production.
Even though the gas phase concentration
of Cl2 increased strongly in the model (see Figure),
the concentration of Cl radicals increased by
less than 5% for the “best estimate” case and the
impact on O3 and other compounds is negligible.
Therefore it was concluded that - at least under
the investigated conditions - this reactions is of
minor importance for the chemistry of the MBL
and the marine sulfur cycle.
A very interesting feature of the acidification
of large sea salt particles that was predicted with
the model is a two-stage acidification of large fresh
sea salt aerosol. This effect is caused by the rapid
change in particle pH due to uptake of acids and
production of acidity during the production of sulfate
and the related change in pH-dependent reactions
rates.
Funding DFG: Emmy Noether Junior Research
Group MarHal GL 353/1-2
Main publication von Glasow [2006b]

80 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
References
Aiuppa, A., Franco, A., von Glasow, R., Allen, A. G., D’Alessandro, W., Mather, T. A., Pyle, D. M.,
& Valenza, M. 2006. The tropospheric processing of acidic gases and hydrogen sulphide in volcanic
gas plumes as inferred from field and model investigations. Atmos. Chem. Phys. Discuss., 6, 11653
– 11680.
Bobrowski, N., von Glasow, R., Aiuppa, A., Inguaggiato, S., Louban, I., Ibrahim, O. W., & Platt, U.
2006. Halogen Chemistry in Volcanic Plumes. J. Geophys. Res., in press.
Keene, W. C., Stutz, J., Pszenny, A. A. P., Maben, J. R., Fisher, E., Smith, A. M., von Glasow,
R., Pechtl, S., Sive, B. C., & Varner, R. K. 2006. Inorganic chlorine and bromine in coastal New
England air during summer. J. Geophys. Res., accepted.
Meyer, R., Büll, R., Leiter, C., Mannstein, H., Pechtl, S., Oki, T., & Wendling, P. 2006. Contrail
observations over Southern and Eastern Asia in NOAA/AVHRR data and intercomparison to contrail
simulations in a GCM. Int. J. Remote Sensing, in press, Also available as Report No. 176,
Institut für Physik der Atmosphäre, DLR Oberpfaffenhofen.
Pechtl, S., Schmitz, G., & von Glasow, R. 2006a. Modeling iodide iodate speciation in atmospheric
aerosol. Atmos. Chem. Phys. Discuss., 6, 10959 – 10989.
Pechtl, S., Lovejoy, E. R., Burkholder, J. B., & von Glasow, R. 2006b. Modeling the possible role of
iodine oxides in atmospheric new particle formation. Atmos. Chem. Phys., 6, 503 – 523.
Ponater, M., Pechtl, S., Sausen, R., Schumann, U., & Hüttig, G. 2006. A state-of-the-art assessment
of the potential of the cryoplane technology to reduce aircraft climate impact. Atmos. Environment,
40, 6928 – 6944.
Schofield, R., Johnston, P. V., Thomas, A., Kreher, K., Connor, B. J., Wood, S., Shooter, D., Chipperfield,
M. P., Richter, A., von Glasow, R., & Rodgers, C. D. 2006. Tropospheric and stratospheric
BrO columns over Arrival Heights, Antarctica during the spring polar vortex split, 2002. J. Geophys.
Res., 111, D22310, doi:10.1029/2005JD007022.
Smoydzin, L., & von Glasow, R. 2006. Do organic surface films on sea salt aerosols influence atmospheric
chemistry? A model study. Atmos. Chem. Phys. Discuss., 6, 10373 – 10402.
von Glasow, R. 2006a. Halogens in the marine boundary layer. Invited talk, UK SOLAS meeting,
Manchester, 17. - 18. July 2006.
von Glasow, R. 2006b. Importance of the surface reaction OH + Cl − on sea salt aerosol for the
chemistry of the marine boundary layer - a model study. Atmos. Chem. Phys., 6, 3571 – 3581.
von Glasow, R., & Crutzen, P. J. 2004. Model study of multiphase DMS oxidation with a focus on
halogens. Atmos. Chem. Phys., 4, 589 – 608.
von Glasow, R., & Crutzen, P. J. 2006. Tropospheric halogen chemistry. In: The Atmosphere (ed. R.
F. Keeling), Vol. 4 Treatise on Geochemistry (eds. H. D. Holland and K. K. Turekian), in press.
Elsevier-Pergamon, Oxford.
von Glasow, R., Sander, R., Bott, A., & Crutzen, P. J. 2002a. Modeling halogen chemistry in the marine
boundary layer. 1. Cloud-free MBL. J. Geophys. Res., 107, 4341, doi: 10.1029/2001JD000942.
von Glasow, R., Sander, R., Bott, A., & Crutzen, P. J. 2002b. Modeling halogen chemistry in the
marine boundary layer. 2. Interactions with sulfur and cloud-covered MBL. J. Geophys. Res., 107,
4323, doi: 10.1029/2001JD000943.
von Glasow, R., von Kuhlmann, R., Lawrence, M. G., Platt, U., & Crutzen, P. J. 2004. Impact of
reactive bromine chemistry in the troposphere. Atmos. Chem. Phys., 4, 2481 – 2497.
WMO (ed). 2006. Scientific Assessment of Ozone Depletion: 2006. World Meteorological Organization
Global Ozone Research and Monitoring Project: Geneva.

2.6. CARBON CYCLE GROUP 81
2.6 Carbon Cycle Group
Ingeborg Levin
Group members
Samuel Hammer (PhD), Renate Heinz (Techn.), Ingeborg Levin (GL), Tobias Naegler (Post Doc),
Michael Sabasch (Techn.), Sebastian Schmitt (Dipl.), Cordelia Veidt (PhD), Felix Vogel (PhD, since
Nov. 2005)
Abstract
High precision greenhouse gases observations (CO2, CH4, N2O, H2O), together with their isotope
ratios as well as related tracer (CO, H2, SF6, 222 Radon) measurements are performed on the global,
continental and regional scale. These measurements are used in combination with regional and trajectory
models to study respective source and sink processes and with global box models to investigate
their global budgets.
H 2 [ppb]
550
500
450
400
Neumayer
Alert
01.01.2004 01.01.2005 01.01.2006 01.01.2007
Date
Figure 2.43: Measurements of atmospheric molecular Hydrogen on flask samples collected in high
northern (Alert, Canadian Arctic) and high southern latitudes (Neumayer Station, Antarctica). Mixing
ratios are generally higher in the southern hemisphere than in the north because one of the major
sinks of atmospheric molecular hydrogen is uptake by soils (see Hammer and Levin, Section 2.6.1 and
Schmitt and Hammer, Section 2.6.4 in this issue).
Overarching topic
Investigation of the regional and global biogeochemical cycles of CO2, CH4, H2 and N2O.
Background
Increasing greenhouse gases in the atmosphere are a major player in Earth climate change; quantitatively
understanding the causes of this increase is an indispensable pre-requisite for future climate
prognoses. The most reliable information on the bio-geochemical cycles of greenhouse gases come from
long term atmospheric observations combined with modelling. The Heidelberg Carbon Cycle Group

82 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
is significantly contributing to this international effort by providing unique (isotopic) measurements
as well as validation tracer techniques and budget modelling.
Main methods
The Group is running a high-precision gas chromatography (GC) laboratory and is responsible
for the stable isotope ratio mass spectrometry (IRMS) laboratory of the Institute. A unique global
network for quasi-continuous 14 CO2 observations is maintained in collaboration with the Radiocarbon
Laboratory (Levin & Hesshaimer [2000], Levin & Kromer [2004], see also Kromer, Section ?? in this
issue). Atmospheric transport tracers such as 222 Radon [Levin et al. , 2002] and SF6, analysed in
collaboration with the Limnology group (Ilmberger, Section 4.2 in this issue) are measured at global
and European sites for transport model validation and source estimates with the Radon-Tracer-Method
[Levin et al. , 1999]. A global box model for CO2 and its isotopes was developed in the last years
[Naegler, 2005] which is currently adapted for methane and its isotope ratios (Veidt et al., Section
2.6.5 in this issue).
Major activities of the year
Important work of the last year concerns the investigation of combined 14 CO2 and CO observations
to determine the regional fossil fuel CO2 (∆FFCO2) component over Europe. Gamnitzer et al. [2006]
and Levin & Karstens [2006b] could show that the uncertainty to derive fossil fuel CO2 mixing ratios
from bottom-up emissions inventories and atmospheric modelling is intolerably large with systematic
biases introducing huge uncertainties (up to a factor of 2-3) in budgeting European carbon sources
and sinks. Further correction/normalisation of the model results with measured CO mixing ratios can
improve the FFCO2 estimates if the CO/FFCO2 ratio of underlying emissions is reliable [Gamnitzer
et al. , 2006]. However, as this is generally not guaranteed, Levin & Karstens [2006a] investigated an
improved method based on weekly integrated measured 14 C-based ∆FFCO2 and hourly CO observations.
The uncertainty of this method was determined with regional model simulations of FFCO2 and
CO and turned out to vary within 15-40% over Europe, depending on the absolute FFCO2 level at a
particular site (see Levin and Karstens, Section 2.6.2 in this issue). It was validated at the Heidelberg
site and will now be adopted at other European CO2 monitoring stations.
A new research project on molecular Hydrogen funded by the EU - EuroHydros - which aims
at investigating the atmospheric Hydrogen budget, i.e. its sources and sinks over Europe as well
as globally, started in August 2006. In this project the IUP Carbon Cycle Group is responsible for
continuous H2 observations in Heidelberg to investigate anthropogenic emissions from fossil fuels (e.g.
car exhaust) as well as the regional soil sink (see Hammer and Levin, Section 2.6.1 in this issue).
On the global and continental European scale, we analyse flask samples from Alert and Neumayer
(see Figure 2.43) as well as from the Schauinsland station in the Black Forest. In addition, chamber
measurements started on the experimental field at Grenzhof in collaboration with the Soil Phyiscs
Group (see Roth, Section 3.1, this issue) to investigate the H2 soil uptake including the soil and
meteorological parameters influencing this sink (see Schmitt and Hammer, Section 2.6.4 this issue).
Our investigations of the global carbon cycle using the world-wide measurements of 14 CO2 will be
continued thanks to extended funding by the DFG (see Naegler and Levin, Section 2.6.3 in this issue).
How are single projects linked:
Projects are linked by common measurement techniques and monitoring stations (i.e. Heidelberg,
Schauinsland, Neumayer, Alert etc.). Data evaluation and interpretation on different scales is naturally
linked through common source and sink distributions of the different greenhouse gases, such as
biospheric, anthropogenic, and chemical oxidation. Common modelling techniques and using tracers
such as 222 Radon or trajectories are applied in the different projects.
Funding
The scientific work of the group is mainly funded by research grants from the EU (CarboEurope-IP,
EuroHydros) and DFG (Atmospheric Radiocarbon).
Cooperations within the institute

2.6. CARBON CYCLE GROUP 83
• Radiokohlenstoff-Labor (Dr. B. Kromer)
• Bodenphysik (Prof. Kurt Roth, Dr. U. Wollschläger)
• Aquatische Systeme (Prof. W. Aeschbach-Hertig, Dr. J. Ilmberger)
External Collaborations:
• MPI für Biogeochemie, Jena (Prof. Martin Heimann, Dr. Armin Jordan, Dr. Ute Karstens,
Olaf Kolle, Prof. Detlef Schulze, Dr. Axel Steinhof)
• Umweltbundesamt (Dr. Ruprecht Schleyer, Frank Meinhardt)
• Forschungszentrum Jülich (Dr. Andreas Volz-Thomas)
• Alfred Wegener Institut Bremerhaven (Dr. Rolf Weller)
• Universität Frankfurt, Institut für Meteorologie (Dr. Andreas Engel)
• LSCE, Gif-sur-Yvette , France, (Prof. Philippe Ciais, Dr. Martina Schmidt)
• Royal Holloway, University of London, Egham, UK (Prof. Euan Nisbet)
• Meteorological Service of Canada, Toronto (Douglas Worthy)
• Krakow University, Poland (Prof. Kazimierz Rozanski)
• and many others.
Future Work
CarboEurope-IP and EuroHydros will be running for the next two years and related research
will be continued, including global modelling of atmospheric molecular hydrogen with GRACE. The
global network of atmospheric 14 CO2 observations will be continued as long as DFG funding permits
including continued global 14 CO2 model investigations.
Peer Reviewed Publications
1. Engel et al. [2006]
2. Naegler & Levin [2006]
3. Naegler et al. [2006a]
4. Naegler et al. [2006b]
5. Rohs et al. [2006]
6. Gamnitzer et al. [2006]
7. Levin & Karstens [2006a]
Other Publications
1. Levin & Karstens [2006b]
Diploma Theses
none
PhD Theses
none

84 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.6.1 Top-down assessments of the regional H2 soil sink strength from
continuous atmospheric observations
Samuel Hammer (participating scientist: Ingeborg Levin)
Abstract Continuous measurements of H2 and 222 Rn in Heidelberg provide new insight into the
regional H2 budget. The radon tracer method was applied to estimate the soil sink strength for
atmospheric molecular Hydrogen.
H 2 [ppb]
H 2 [ppb] corrected
570
540
510
480
540
510
480
450
a
b
420
17.07.2006 19.07.2006 21.07.2006 23.07.2006 25.07.2006
Figure 2.44: a: Summer situation with pronounced diurnal cycles of H2 and CO. b: The H2 mixing
ratio is corrected here for direct anthropogenic emissions by the means of ”excess” CO and displayed
together with 222 Rn. The shaded areas mark stable nocturnal inversions, used to estimate the H2 soil
sink strength.
Background The recent atmospheric H2 budget
is not well established quantitatively. Important
sources are combustion processes as well as
oxidation of CH4 and Non Methane HydroCarbons
in the atmosphere. The global atmospheric
H2 budget is closed by two major sinks: the oxidation
of H2 initiated by the reaction with OH
radicals and the uptake by soils. The latter is believed
to be the dominating part leading to a total
atmospheric lifetime of H2 of about two years.
The present uncertainties in the budget are large.
Especially the soil sink strength differs up to a factor
of two between the different budget estimates.
Here we report on a method to derive the H2 soil
sink directly from atmospheric measurements.
Methods and results A combined GC system
is used for quasi-continuous parallel measurements
of CO2, CH4, CO, H2, N2O and SF6 mixing
ratios. The determined H2 calibration is linked to
the CSIRO scale to within 1-2%, with a precision
of the H2 measurements of generally better
than 1% [Hammer et al., in preparation]. 222 Rn
is monitored on a half hourly basis, via its daughter
activity with the static filter method [Levin
et al. , 2002]. Panel a in Figure 2.44 shows summer
situations with pronounced diurnal cycles of
H2 and CO. Panal b provides the H2 mixing ratio
corrected for direct anthropogenic emissions,
which occur mainly during morning rush hours,
by means of ”excess” CO assuming an H2/CO ra-
300
200
100
12
9
6
3
0
222 Rn [Bq/m³]
CO [ppb]
tio of 0.4. During strong night-time inversions the
H2 soil sink decreases boundary layer H2 while
222 Rn emitted by the soil increases at the same
time. Both tracers recover in the early morning
hours due to enhanced vertical mixing. The radon
tracer method (Levin et al. [1999] and Schmidt
et al. [2001]) can be used to parameterise vertical
mixing during these inversion situations and calculate
the H2 soil sink strength (shaded areas in
Figure 2.44b). For the period shown we estimate
H2 soil sink strengths between 3·10 −5 [g/(m 2 · h)]
and 9 · 10 −5 [g/(m 2 · h)], with a mean value of
5 · 10 −5 [g/(m 2 · h)]. The error of this estimate is
in the order of 35% and dominated by the uncertainty
of the 222 Rn flux. Our results agree reasonably
well with the reported H2 soil sink strength
derived from chamber measurements (see Schmitt
et al., Section 2.6.4 in this issue). The advantage
of using direct atmospheric measurements to
estimate the H2 soil sink, in contrast to closed
chamber techniques is that a much larger catchment
area and thus many different soil types in
the measurement area are considered.
Outlook/Future work It is now planned to
investigate the H2 budget, including the H2 isotopes,
by means of the atmospheric box model
GRACE [Naegler, 2005].
Funding This PhD work is funded by the EU
projects EuroHydros and CarboEurope - IP.

2.6. CARBON CYCLE GROUP 85
2.6.2 Inferring high-resolution fossil fuel CO2 records at continental sites
from combined 14 CO2 and CO observations
Ingeborg Levin (participating scientist: Ute Karstens, MPI Biogeochemistry, Jena)
Abstract An uncertainty estimate of a purely observational approach to derive hourly regional fossil
fuel CO2 offsets (∆FFCO2) from weekly integrated 14 CO2 and hourly CO observations at continental
CO2 monitoring sites is presented. Results are based on a regional modelling study over Europe, and
are validated with high-resolution campaign measurements in Heidelberg.
Figure 2.45: Left: Monthly mean ∆FFCO2 as simulated by REMO for February 2002 for the lowest
model level at 30m above ground. Right: RMS difference of CO-based ∆FFCO2 estimates (from
REMO results according to Equation 2.4) and the original estimates displayed in the left panel.
Background The CO2 budget over Europe and
other highly populated regions in the world is
largely influenced by anthropogenic emissions (see
Figure 2.45). Separating the fossil fuel from the
natural biogenic signal in the atmosphere is, therefore,
a crucial task when CO2 exchange fluxes
of the continental biosphere shall be determined
from atmospheric observations and inverse modelling.
Levin et al. [2003] showed that fossil
fuel CO2 can be ”measured” in the atmosphere
via 14 CO2 observations, however, not routinely at
high temporal resolution. Therefore other fossil
fuel tracers, in particular CO, were used for this
purpose (e.g. Gamnitzer et al. [2006]). CO is,
however, not a conservative tracer in the atmosphere
and needs ongoing calibration if it shall be
applied for quantitative estimates of the fossil fuel
CO2 component.
Methods and results We propose to estimate
hourly ∆FFCO2 mixing ratios at a polluted site
from weekly integrated 14 CO2 measurements and
hourly CO observations according to
(∆F F CO2) hourly = (2.3)
∆CO meas
14C−based
(∆F F CO2) weekly
hourly · �
∆COmeas �
hourly
weekly
The uncertainty of this method can be tested
using REgional MOdel (REMO, Chevillard et al.
[2002]) simulations of hourly time series of CO
and fossil fuel CO2, based on emissions inventories
of these trace gases. From these we can directly
determine the Root Mean Square (RMS) deviation
between a CO-based estimate of re-calculated
hourly ∆FFCO2 (in analogy to Equation 2.3)
(∆F F CO2) re−calculated
hourly = (2.4)
∆CO model
�
(∆F F CO2)
hourly ·
model
�
hourly
weekly
�
∆COmodel �
hourly
weekly
and the original model-estimated hourly
∆FFCO2. These RMS deviations range from
about 15% up to 40% for continental Europe, with
larger errors in areas with little ∆FFCO2 (see
Figure 2.45). These uncertainties are, however,
still much smaller than any model- and emissions
inventory-based approach and could be confirmed
by high-resolution campaign data of 14 CO2 and
CO in Heidelberg published by Gamnitzer et al.
[2006].
Outlook/Future work The proposed method
will now be applied at other CarboEurope monitoring
stations.
Main publications: Levin & Karstens [2006a],
Levin & Karstens [2006b]
Funding EU-Project CarboEurope-IP

86 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.6.3 Carbon cycle constraints derived from the interhemispheric ∆ 14 C
difference
Tobias Naegler (participating scientist: Ingeborg Levin)
Abstract With the help of the two-dimensional global (radio-)carbon cycle model GRACE, we
estimated the components driving the observed interhemispheric gradient in ∆ 14 C and its implications
for carbon cycle dynamics on the hemispheric scale.
Background The observed interhemispheric
gradient in ∆ 14 CO2 is driven by the imbalance of
14 C sources and sinks between both hemispheres.
Consequently, the model-based analysis of the observations
allows to constrain carbon cycle dynamics
on the hemispherical scale.
∆ 14 C N−S difference in %o
6
4
2
0
−2
−4
−6
−8
Observed and simulated NS−gradient
−10
−12 observed N−S difference
−14
simulated N−S difference
observed difference minus 7.5%o
−16
1980 1984 1988 1992 1996 2000 2004
Figure 2.46: Observed and simulated interhemispheric
∆ 14 C North-South difference.
Methods and results With the help of the
GRACE model [Naegler, 2005], we simulated an
interhemispheric ∆ 14 C different between northern
mid- and southern polar latitudes which is on average
about 7.5� smaller than the observed difference
between Jungfraujoch and Neumayer station
(Fig. 2.46). However, both the model and the observations
show a similar decreasing trend in the
N-S difference of about 3� per decade.
Components of tropospheric ∆ 14 C gradient
1976 1980 1984 1988 1992 1996 2000 2004 −20
high NH ∆
10
5
0
−5
−10
−15
14 C ↔ low SH ∆ 14 C SH
low NH ∆ 14 C ↔ high SH ∆ 14 strato
bio
ocean
natural
bomb
industry
fossil
interh
C
Figure 2.47: Components driving the simulated
interhemispheric ∆ 14 C N-S difference.
In the model, the interhemispheric ∆ 14 C difference
since the 1980s is mainly driven by three
components (Figure 2.47): Predominant release
of 14 C-free fossil fuel CO2 in the northern hemisphere
is decreasing ∆ 14 C in the north. As an
opposing effect, due to lower sea surface ∆ 14 C
and higher wind speeds, the oceanic 14 C uptake
in the southern hemisphere is stronger than the
uptake in the north, causing a ∆ 14 C depletion in
15
%o⋅ yr −1
the south relative to the north. Third, interhemispheric
transport is partly levelling off any ∆ 14 C
difference arising from an imbalance in (radio-
)carbon sources and sinks between both hemispheres
(Figure 2.47). Other possible components
of an interhemispheric ∆ 14 C difference in
the model are small compared to these three main
drivers of the difference. The model results also
illustrate that the decreasing trend in the interhemispheric
difference is caused by the decreasing
hemispherical imbalance of oceanic 14 C uptake,
whereas the fossil fuel component of the interhemispheric
gradient has remained rather constant.
The (temporally rather constant) underestimation
of the observed north-south ∆ 14 C difference
in the model can in principle be caused by
a constant underestimation of the contribution of
any of the components driving the difference. As
demonstrated by Naegler & Levin [2006], the integrated
hemispheric oceanic 14 C uptake in the
model is in good agreement with the observed excess
14 C inventories in the ocean. Also, fossil fuel
CO2 emissions are known with only little uncertainty
and the interhemispheric exchange time in
GRACE is rather well constrained by SF6 observations.
Therefore we conclude that ocean 14 C
exchange, fossil fuel fluxes as well as the interhemispheric
air mass exchange in GRACE contribute
only little to the data-model mismatch.
Consequently, it is probably the simulated terrestrial
biosphere which is to be held responsible
for the underestimation of the ∆ 14 C difference.
As the biosphere module in GRACE has
no representation of the finite lifetime of carbon
in living biomass and the parameters of the biosphere
module (such as turnover times, pool sizes,
and respiration) are subject to large uncertainties,
it is quite plausible to assume that biosphereatmosphere
(radio-)carbon exchange is not yet
well represented in the model.
Outlook/Future work As a consequence of
these results, we will focus on the improvement
of the biosphere module in GRACE and analyse
the biospheric excess 14 C inventory constraints on
biosphere dynamics.
Main publications: Naegler & Levin [2006],
Naegler et al. [2006a,b]
Funding This work is funded by the DFG.

2.6. CARBON CYCLE GROUP 87
2.6.4 Investigating the soil sink of molecular Hydrogen (H2)
Sebastian Schmitt (participating scientist: Samuel Hammer)
Abstract Aiming at a better understanding of the environmental cycle of different trace gases a
setup is established to quantify the atmosphere-soil exchange of H2, CH4, N2O, CO2 and CO. With
a main focus on the parmeters which determine the H2 soil sink the setup and additional devices for
measuring soil moisture, temperature, 222 Rn efflux and soil gas profiles are applied and tested at the
Grenzhof site near Heidelberg.
Figure 2.48: The setup for measuring the H2 flux to the soil as it is installed at the Grenzhof near
Heidelberg. The chamber is made of a clear material for disturbing biological activity at a minimum.
The diagramm shows a strong dependence of the flux on soil moisture. Measured uptake rates range
−6 g
from (7.1 ± 0.7) · 10 h·m2 −5 g
to (4.9 ± 0.5) · 10 h·m2 Background Following an expanding use of the
fuel cell technology the concentration of molecular
Hydrogen in the troposphere could rise significantly
due to leakages in H2 production and
transport. As in the troposphere molecular Hydrogen
is oxidized by OH radicals it acts as an indirect
greenhouse gas consuming tropospheric OH
which is also an important oxidant of CH4. It is
therfore necessary to better understand the mechanisms
in the environmental H2 cycle in which the
soil is known as the most important, but not yet
properly quantified sink [Conrad, 1996].
Methods and results The fluxes of the trace
gases between the atmosphere and the soil are
determined with the closed chamber technique.
From the chamber samples for gas chromatographic
analysis are taken to monitor the time dependent
variations of the trace gases inside. Measurements
of samples and the associated analysis
of other environmental parameters show that
the H2 soil sink is highly dependent on tempera-
ture and soil moisture. The fluxes measured range
−6 g
from (7.1±0.7)·10 h·m2 −5 g
to (4.9±0.5)·10 h·m2 ,
results that could be confirmed by estimates made
on the basis of the continuous H2 measurements
performed by our group on top of the IUP building
(see Hammer & Levin, Section 2.6.1 in this
issue).
Outlook/Future work Additional measurements
( 222 Rn efflux, soil gas profile studies, isotopic
signature of the uptake) will be made at the
Grenzhof site to further investigate the fundamental
processes responsible for the H2 soil uptake,
which at present is thought to be due to encymatic
oxidation. Moreover, possible correlations
between the different trace gas fluxes are investigated
because they could provide valuable information
about underlying chemical and biochemical
processes.
Funding This Diploma work is funded by the
EU-project EuroHydros.

88 CHAPTER 2. ATMOSPHERE AND REMOTE SENSING
2.6.5 Observation of δ 13 C and δD in atmospheric methane and implementation
of a methane module to the GRACE model
Cordela Veidt (participating scientists: Tobias Naegler, Renate Heinz, Ingeborg Levin)
Abstract The isotopic composition of methane from different clean air sampling sites is measured.
Long-term trends and seasonal cycles inherit information about the development of methane sources
and sinks. The sources and sinks and the concentration and composition of atmospheric methane will
be simulated with the 28-box model GRACE and evaluated with available measured datasets.
Figure 2.49: Methane mixing ratios and growth
rates in high northern and high southern latitudes.
Alert: N82 ◦ 25 ′ W62 ◦ 52 ′ ; Neumayer station:
S70 ◦ 39 ′ W8 ◦ 15 ′ . Tanks: high-volume biweekly
integrated (Alert) and spot (Neumayer)
samples. Flasks: small-volume biweekly spot
samples.
Background The different sources of methane,
both natural and anthropogenic, show a different
isotopic composition and all sink processes are
fractionating methane isotopes to a different extent.
Therefore, relative changes in CH4 sources
also cause changes in the isotopic composition of
atmospheric CH4. The isotopic signature of the
atmospheric methane does not only correspond to
shifts in the sources, but also depends on the total
amount of atmospheric methane into which the
methane of the sources is being diluted. Therefore
and in contrast to total methane, isotopic ratios
in global atmospheric methane adjust only slowly
to a new equilibrium state. To identify source alterations
which occured during the past decades,
model simulations of the atmospheric response,
therfore need to be applied.
Methods and results High volume air samples
from Neumayer station (Antarctica), Alert
(Nunavut, Canada) and Izaña (Tenerife, Spain)
with temporal resolution of about a fortnight are
shipped to Heidelberg and methane mixing ratios
are measured here by gas chromatography. To
determine the isotopic composition the methane
from about 500l of air has to be quantitatively
extracted. δD of about 2/3 of the obtained CH4
is measured with a tunable diode laser absorption
spectometer (TDLAS) because of its small standard
deviation of 1.0� for the whole process. The
remaining part of the sample is catalytically combusted
to CO2 and H2O, the H2O is reduced to
H2 and δ 13 C and δD are measured by mass spectrometry.
The standard deviation for the whole
process is σ δ 13 C = 0.07� and σδD = 2.0�. Data
evaluation of the set of CH4 samples displayed
in Figure 2.49 is not yet completed, the following
results, especially δD, should thus be taken
as preliminary. Linear trend in δ 13 C: 1988-1992
Neumayer +0.01 to +0.04�/yr. 1992-1999 Alert
+0.01 to +0.04�/yr, Izaña 0 to +0.05�/yr,
Neumayer +0.03 to +0.06�/yr. From 1999-2004
there is no trend observed for Alert while Neumayer
shows a small maximum in 1999/2000 with
a succeeding negative trend till 2004 of about -
0.01 to -0.04�/yr. Linear trend in δD: 1992-1997
Alert +2 to +3�/yr, Izaña +1.5 to +2.8�/yr,
Neumayer +1.2 to +3.5�/yr. For the period
1997 to 2004 and 2005, respectively, there is no
trend observed at Alert and Neumayer. A peakto-peak
amplitude of the seasonal cycle of δ 13 C
at Alert is 0.25 to 0.6�, and at Neumayer 0.15 to
0.3�. For δD we observe at Alert 6 to 10�, and
at Neumayer 4 to 7�.
To simulate the atmospheric methane trends under
changing methane source configurations a
methane source module has been added to the
28-box model GRACE [Naegler, 2005]. Its atmosphere
consists of a planetary boundary layer, a
free troposphere, and three stratospheric layers.
The layers of each hemisphere are segmented into
three latitudinal boxes.
Outlook / Future work All established
methane sink processes will be included in the atmosphere
of the GRACE model. After evaluation
of our and all other published source and atmospheric
data, the atmospheric constitution during
the last three centuries will be simulated according
to different source and sink scenarios. Comparison
of measured and modelled data should expose
improved information about the development
of methane sources during the past decades.

2.6. CARBON CYCLE GROUP 89
References
Chevillard, A., Karstens, U., Ciais, P., Lafont, S., & Heimann, M. 2002. Simulation of atmsopheric
CO2 over Europe and western Siberia using the regional scale model REMO. Tellus, 54B, 872–894.
Conrad, Ralf. 1996. Soil Microorganisms as Controllers of Atmospheric Tracer Gases (H2, CO, CH4,
OCS, N2O, and NO). Microbiol. Reviews, 60(4), 609–640.
Engel, A., Möbius, T., Haase, H.-P., Bönisch, H., Wetter, T., Schmidt, U., Levin, I., Reddmann, T.,
Oelhaf, H., Wetzel, G., Grunow, K., Huret, N., & Pirre, M. 2006. Observation of mesospheric air
inside the arctic stratospheric polar vortex in early 2006. Atmos. Chem. Phys., 6, 267–282.
Gamnitzer, U., Karstens, U., Kromer, B., Neubert, R. E M., Meijer, H. A. J., Schroeder, H., & Levin,
I. 2006. Carbon monoxide: A quantitative tracer for fossil fuel CO2? J. Geophys. Res., 111,
D22302, doi:10.1029/2005JD006966.
Levin, I., & Hesshaimer, V. 2000. Radiocarbon - a unique tracer of global carbon cycle dynamics.
Radiocarbon, 42(1), 69–80.
Levin, I., & Karstens, U. 2006a. Inferring high-resolution fossil fuel CO2 records at continental sites
from combined 14 CO2 and CO observations. accepted for publication in Tellus B.
Levin, I., & Karstens, U. 2006b. Quantifying fossil fuel CO2 over Europe. In: Dolman, A. J.,
Freibauer, A., & Valentini, R. (eds), Observing the Continental Scale Greenhouse Gas Balance of
Europe. Heidelberg, Germany: Springer-Verlag, Ecological Studies Series.
Levin, I., & Kromer, B. 2004. The tropospheric 14 CO2 level in mid-latitudes of the Northern Hemisphere
(1959-2003). Radiocarbon, 46(3), 1 261–1 272.
Levin, I., Glatzel-Mattheier, H., Marik, T., Cuntz, M., Schmidt, M., & Worthy, D.E. 1999. Verification
of German methane emission inventories and their recent changes based on atmospheric
observations. J. Geophys. Res., 104(D3), 3447–3456.
Levin, I., Born, M., Cuntz, M., Langendörfer, U., Mantsch, S., Naegler, T., Schmidt, M., Varlagin,
A., Verclas, S., & Wagenbach, D. 2002. Observations of atmospheric variability and soil exhalation
rate of radon-222 at a Russian forest site. Technical approach and deployment for boundary layer
studies. Tellus B, 54(5), 462–475.
Levin, I., Kromer, B., Schmidt, M., & Sartorius, H. 2003. A novel approach for independent budgeting
of fossil fuel CO2 over Europe by 14 CO2 observations. Geophys. Res. Letters, 30(23),
doi:10.1029/2003GL018477.
Naegler, T. 2005. Simulating Bomb Radiocarbon: Consequences for the Global Carbon Cycle. PhD
thesis, University of Heidelberg, Heidelberg, Germany.
Naegler, T., & Levin, I. 2006. Closing the Global Radiocarbon Budget 1945-2005. J. Geophys. Res.,
111, D12311, doi:10.1029/2005JD006758.
Naegler, T., Ciais, P., Rodgers, K., & Levin, I. 2006a. Excess radiocarbon constraints on airsea
gas exchange and the uptake of CO2 by the oceans. Geophys. Res. Letters, 33, L11802,
doi:10.1029/2005GL025408.
Naegler, T., Ciais, P., Orr, J. C., Aumont, O., & Rödenbeck, C. 2006b. On evaluating ocean models
with atmospheric potential oxygen. TELLUS, (in press).
Rohs, S., Schiller, C., Riese, M., Engel, A., Schmidt, U., Wetter, T., Levin, I., Nakazawa, T., & Aoki,
S. 2006. Long-term changes of methane and hydrogen in the stratosphere in the period 1978-2003.
J. Geophys. Res., 111, D14315, doi:10.1029/2005JD006877.
Schmidt, M., Glatzel-Mattheier, H., Sartorius, H., Worthy, D. E., & Levin, I. 2001. Western European
N2O emissions: A top-down approach based on atmospheric observations. J. Geophys. Res., 106,
5507–5516.

Terrestrial Systems
3.1 Soil Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
3.2 Ice and Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
91

Overview
We study the whole range of physical processes in near-surface land systems, including the land
cryosphere, at spatial scales ranging from sub-millimeter to hundreds of kilometers. These processes
are relevant for a spectrum of hot environmental issues including water resources in arid and semi-arid
regions, contamination of groundwater by agrochemicals and waste disposal site, as well as past and
present climate changes. Current main research fields are
1. fundamentals of transport processes in soils and groundwater
2. geophysical near-surface exploration and monitoring
3. thermal and hydraulic dynamics of permafrost in a changing environment
4. climate and environmental archives in glaciers and ice shields
The group is organized in two major subgroups: “Soil Physics” covering research fields 1. . . 3 and “Ice
and Climate” covering research field 4. An overview of their current research activities is given on
pages 94ff and 105ff, respectively.
Future Work
Important perspectives for the next reporting period include
1. development of the Grenzhof test site to include (i) long lines of ground-penetrating radar (GPR)
measurements, (ii) time-series of electrical resistivity tomography (ERT) sections, and (iii) fluxes
of gaseous emissions from the soil (group of I. Levin),
2. identify and develop a new test site specifically for GPR with a highly heterogeneous subsurface
architecture,
3. investigation of reflection and scattering properties of soil surfaces for electromagnetic waves in
the frequency range between 300 MHz and 3 GHz,
4. explore the permafrost distribution in Western Tibet (Aksai Chin region) and set up two monitoring
stations to study the dynamics of permafrost in high, dry, and cold environments and,
eventually, the impact of a warming climate,
5. new Alpine ice core drillings to bedrock at Piz Murtel and at the underground of the Eisriesenwelt
6. re-designing of the Air Chemistry Observatory at the Antarctic Neumayer Station III
More details are again given in the respective summaries.
93

94 CHAPTER 3. TERRESTRIAL SYSTEMS
3.1 Soil Physics
Group members
Prof Dr. Kurt Roth, head of group
Angelika Gassama, Staff
Dipl. Phys. Holger Gerhards, PhD student
Moritz Mie, diploma student
Dipl. Phys. Fereidoun Rezanezhad, PhD student
Dipl. Geol. Philip Schiwek, PhD student
Dipl. Phys. Klaus Schneider, PhD student
Carolin Ulbrich, diploma student
Dr. Hans-Jrg Vogel, Post Doc, on leave
Dr. Ute Wollschlger, Post Doc
Abstract
We (i) experimentally study transport processes in soils and groundwater – water, solutes, heat – from
the lab- to the field-scale, (ii) develop and apply methods for near-surface geophysical exploration and
monitoring, and (iii) explore the thermal and hydraulic dynamics of permafrost on the Tibetan plateau
with a focus on climate warming.
Scientific Objectives
1. Qualitatively understand flow processes beyond the classical Richards-regime, specifically gravitydriven
flow instabilities and the dynamics of the capillary fringe.
2. Quantify effective hydraulic material properties for a very wide range of hydraulic states.
3. Develop ground-penetrating radar (GPR) for directly measuring soil water content and electrical
resistivity tomography (ERT) for quantitative monitoring of solute transport.
4. Monitor and qualitatively understand the dynamics of the permafrost in the wet and comparatively
warm region of the Eastern Tibetan plateau.
Overarching topic
To contribute to the fundamental understanding of transport processes in terrestrial systems, mostly
soils. These may be characterized as strongly and stochastically forced processes with a highly nonlinear
dynamics in a multi-scale architecture.
Background
Transport of water, dissolved chemicals, and heat are intimately linked in soils and they are an
important, often crucial aspect of many environmental issues like quantity and quality of groundwater,
irrigation and soil salinization, coupling of soil and atmosphere, and stability of permafrost soils.
Despite their acknowledged significance, these processes are hardly ever represented accurately and
with sufficient detail in models of environmental systems. The fundamental reason for this is that
their is a huge disparity between the scale at which the underlying physics is understood, typically
much less than one meter, and the scale at which a process representation is required for modeling
the environment, typically hundreds of meters to tens of kilometers. The same is true for other
environmental compartments like the atmosphere or the oceans. There, however, appropriate scaling
laws facilitate the closing of the gap for many processes. In terrestrial systems, this is prevented by
the multi-scale architecture of the medium.
A further challenge of terrestrial systems is the inherent and extreme nonlinearity. For instance,
the hydraulic conductivity depends strongly on water content and can easily vary by some 10 orders of
magnitude in a coarse-textured soil. Depending on the external forcing, such a range may be covered
within weeks or months during the summer dry-out or it is swept within minutes during a heavy
rainfall or flooding event.
With our research, we target both major issues: the local processes themselves and the efficient
and accurate determination of the multi-scale architecture.

3.1. SOIL PHYSICS 95
Main methods
Multi-Step Outflow Measurement Hydraulic material properties are estimated from experiments
where the boundary condition is changed in discrete steps, the resulting outflow is measured,
and the whole setup is inverted numerically.
Hele-Shaw Cell A quasi-twodimensional porous medium is constructed by filling the 3. . . 6 mm gap
between two glass plates with sand. Transmitted light is a good proxy for volumetric water
content and dye tracers facilitated the measurement of flow fields. Such Hele-Shaw cells allow
monitoring of flow and transport processes with very high spatial and temporal resolutions.
Ground-Penetrating Radar (GPR) Propagation of electromagnetic energy through porous media
depends strongly on their dielectric properties which in turn, at frequencies between some
50 MHz and 2 GHz, depends strongly on liquid water content. This in turn depends on soil
texture which often changes discontinuously in natural porous media, thereby leading to strong
reflectors. We have demonstrated that multi-channel GPR-measurements yield both the depth
of the reflectors and the average water content between them. In the meantime, we use this
method operationally in simple settings and work on improving it for more complicated ones.
Electrical Resistivity Tomography (ERT) The electrical potential at the soil surface that results
from injecting a very-low frequency, mHz to Hz, electrical current into the subsurface reflects the
spatial distribution of the electrical conductivity. Combining the results from a large number
of injection points leads to an estimate of that distribution which in turn is determined by soil
texture, soil water content, and solute concentration.
Soil-Weather Monitoring Station Automatic logging of profiles of soil temperature and liquid
water content together with atmospheric variables (temperature, precipitation, wind velocity,
humidity, net radiation or even its components, pressure, snow height) allow the microclimatic
characterization of a particular site. We operate such a station at the Grenzhof test site and
several of them on the Tibetan plateau.
Grenzhof Test Site This site near Heidelberg is our testbed for developing and demonstrating measuring
and monitoring techniques as well as for exploring the emerging field of hydrogeophysical
approaches where hydraulic experiments and and geophysical observations are inverted jointly
in order to arrive at more robust estimates of large-scale material properties.
Main activities
1. study flow instabilities and the dynamics of the capillary fringe in Hele-Shaw cells
2. improve multi-step outflow methods, in particular the evaporation methods we developed
3. develop and implement improved analysis tools for multi-channel GPR
4. monitor and analyze thermal and hydraulic dynamics at three permafrost sites on the Tibetan
plateau
5. explore synthetic aperture radar (SAR) satellite images from estimating soil surface water contents
Funding
1. DFG RO 1080/8 “Vorhersage einfacher Transportphnomene in Bden auf der Feldskala”
2. DFG RO 1080/9 “Hochauflsende experimentelle Untersuchung von Fluss und Transport in
porsen Medien”
3. DFG RO 1080/10 “Dynamics of Active Layer on Qinghai-Xizang Plateau”

96 CHAPTER 3. TERRESTRIAL SYSTEMS
Cooperation within the institute and with groups outside of the institute
1. Dr. Julia Boike, HGF Young Research Group SPARC, Alfred Wegener Institute, Potsdam
2. Prof. Dr. Peter Bastian and Dr. Olaf Ippisch, Institute of Parallel and Distributed Systems,
University of Stuttgart
3. Prof. Dr. Qihao Yu and Prof. Dr. Huijun Jin, Institute for Cold and Arid Regions Environmental
& Engineering Research (CAREERI), Chinese Academy of Sciences, Lanzhou, China
4. Dr. Frank Brner, Dresdner Grundwasserforschungszentrum (DGFZ), Dresden
5. Dr. Benedikt Oswald, Paul Scherrer Institute (PSI), Villigen, Schweiz
Future Work
see Overview
Peer Reviewed Publications
1. Leidenberger et al. [2006]
2. Schneider et al. [2006]
Diploma Theses
1. Schneider [2005]
PhD Theses
1. Braun [2006]

3.1. SOIL PHYSICS 97
3.1.1 Unstable Gravity-driven Fingering Flow in Unsaturated Porous Media
Fereidoun Rezanezhad
Abstract Wetting front instability, or unstable gravity-driven fingering, can occur during vertical
infiltration through initially dry sand. With the aim of studying the physical process concerning of
the fingering phenomena in two dimensions, experiments of water infiltration through a Hele-Shaw
cell of multi-layered sand were carried out in the laboratory. Using imaging technique, we study the
dynamics of water saturation in fingering flow for different flow conditions.
depth [m]
depth [m]
0
0.2
0.4
width [m]
0 0.2 0.4
0.6
0.8
1.0
1.2
1.4
time:15 min
a
0
0.1
0.2
0.3
0.4
0.5
width [m]
0 0.2 0.4
0
0.2
0.4
width [m]
0 0.2 0.4
0.6
0.8
1.0
1.2
1.4
time:30 min
depth [m]
0
0.1
0.2
0.3
0.4
0.5
0
0.2
0.4
width [m]
0 0.2 0.4
0.6
0.8
1.0
1.2
1.4
time:75 min
width [m]
0 0.2 0.4
0
0.2
0.4
width [m]
0 0.2 0.4
0.6
0.8
1.0
1.2
1.4
time:125 min
depth [m]
0
0.1
0.2
0.3
0.4
0.5
0
0.2
0.4
width [m]
0 0.2 0.4
width [m]
0 0.2 0.4
0.6
0.8
1.0
1.2
1.4
time:200 min
original image
normalized image deconvoluted image
b c d
1.00
0.88
0.75
0.62
0.50
0.38
0.25
0.12
0
depth [m]
0
0.1
0.2
0.3
0.4
0.5
width [m]
0 0.2 0.4
depth [m]
0
0.1
0.2
0.3
0.4
0.5
width [m]
0 0.2 0.4
mobile core
immobile fringe
Figure 3.1: Left: a) Fingering patterns observed by Light Transmission Method (LTM) during water
and dye infiltration into the multi-layered medium. b) Original observed image. c) Normalized image
to visualize the water saturation. d) Deconvoluted image using the Point Spread Function (PSF).
Right: The separation of the water phase into a mobile component (core) and an immobile one
(fringe) observed using dye tracer infiltration.
Background and Observations The fluid
flow through preferential paths or fingers is important
in the hydrological processes of infiltration
through the soil profile. Fingered flow in porous
media was studied, both in the petroleum industry
to better understand oil recovery and in the environmental
sciences as an instance of preferential
flow of water through soil. Fingered flow occurs
in homogeneous coarse grained materials when the
infiltration rate is below the saturated hydraulic
conductivity (Ks) and gravitational influences on
the imbibing solution dominate the forces of capillary.
We established such conditions in a Hele-
Shaw cell where a layer of fine sand was placed on
top of a coarse sand. Flow instability is induced at
the transition from the fine-textured sand to the
coarse-textured sand. The fingers are disturbed
within the heterogenous middle-layer and reappear
in the uniform layer below (Fig.1).
Funding DFG project RO 1080/9-1&2, 2005-
2006
Methods and results We improved the Light
Transmission Method (LTM) to measure the dy-
namics of water saturation within flow fingers in
great detail with high spatial and temporal resolution.
This was achieved by adding a deconvolution
procedure using the Point Spread Function
(PSF) to correct the measurements for multiple
light scattering in observed image. The method
was calibrated using X-ray absorption. Additionally,
after stabilization of the fingered flow pattern,
we applied a dye tracer to visualize the velocity
field within flow fingers. We analyzed the
dynamics of water within the finger tips, along the
finger core behind the tip, and within the fringe of
the fingers during lateral growth. Our results confirm
previous findings of saturation overshoot in
the finger tips and revealed a saturation minimum
behind the tip as a new feature. The finger development
was characterized by a gradual increase
in water content within the core of the finger behind
this minimum and a gradual widening of the
fingers to a quasi-stable state. In this state, a
sharp separation into a core with fast convective
flow and a fringe with exceedingly slow flow was
detected.
Main Publication [Rezanezhad et al. , 2006]

98 CHAPTER 3. TERRESTRIAL SYSTEMS
3.1.2 Novel Evaporation Experiment to Determine Soil Hydraulic Properties
Klaus Schneider
Abstract A new method to determine soil hydraulic properties in the dry and very dry range is
developed and analysed. The data are inverted under the assumption that the coupling between the
soil and the well-mixed atmosphere can be modelled by a boundary layer with a constant transfer
resistance.
Background An important issue in soil physics
is the determination of the hydraulic parameters
of soils. If the soil water characteristic θ(ψm)
and the conductivity function K(θ) of a soil are
known, its hydraulic dynamics can be simulated
using Richards’ equation.
Several methods exist to determine the hydraulic
properties in the laboratory. For the wet
range of potentials the multistep-outflow (MSO)
method is well established. However this method
is fundamentally limited by the ambient air pressure.
Unlimited potentials are theoretically possible
with evaporation experiments. However traditional
evaporation experiments, due to the useage
of tensiometers, are again limited by the air entry
point of the tensiometer, or the vapour pressure
of water, whichever is higher.
To obtain valid hydraulic properties also for
the dry range, a new evaporation method and a
numerical model to determine soil hydraulic properties
by inversion was developed and tested.
Methods and results The bottom of the soil
sample is closed, its top is closed by a 30 mm high
gas-tight head space. A constant flow of air is established
through the head space to remove the
water vapour and thereby set the potential. The
difference of water vapour content before and after
the evaporation chamber (measured accurately
by infrared absorption spectroscopy) and the air
flow through the chamber quantify the water flux
at the upper boundary of the soil sample, while
the relative humidity and the temperature in the
evaporation chamber define the equivalent matric
potential of the air. The latter is set by an air
conditioner.
Hydraulic parameters are estimated from the
evaporation measurements using inverse modelling.
The forward model integrates Richards’
equation with an effective conductivity which accounts
for water vapour movement. The soilatmosphere
boundary layer at the upper boundary
is explicitely modelled as a diffusive layer of
constant thickness rb. This is a nonlinear boundary
condition and was implemented in the forward
model.
Since inverse methods are not straightforward
well coded standard procedures, validating steps
are important, e.g. sensitivity and parameter identification
analyses. These are currently done.
water vapour partial pressure / kPa
flux / (mm/h)
deviation / %
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
40
20
0
−20
−40
−60
water vapour partial pressue
temperature
potential
measured flux
simulated flux
deviation
−80
0 100 200 300
time / h
400 500 600
Figure 3.2: Results of an evaporation experiment
with an undisturbed soil sample. Measured quantities
pw and T (upper frame), matric potential
at the upper boundary calculated from pw
and T and measured and simulated outflux (middle
frame). Notice that the latter two practically
overlap after t > 30 h. The discrepancy at
early times is attributed to thermal processes not
considered in the model. The relative deviation
(j w exp − j w model )/jw exp is shown in the bottom frame
together with the 1σ measuring uncertainty (gray
band).
Outlook/Future work The experiment will be
extended to allow a wider range of boundary conditions.
Main publications [Schneider et al. , 2006]
300
299
298
297
296
295
294
293
292
291
0
−50
−100
−150
−200
−250
−300
temperature / K
matric potential / MPa

3.1. SOIL PHYSICS 99
3.1.3 Physical processes in the capillary fringe
Moritz Mie
Abstract In order to understand the impact of different factors on size and shape of the capillary
fringe, we use high-resolution measurements of the water saturation obtained from imaging techniques.
The most important part of this work is to explain the nonlinear behavior of the capillary fringe by
changing the water table. Moreover we try to understand the connection between this non-linear
behavior and the hysteresis of the soil-water characteristic.
motor control Hele−Shaw cell
digital camera
Figure 3.3: Sketch of the experimental setup: A transparent sand-filled Hele-Shaw cell is placed
between a diffusive light source and a digital camera. The water table in the cell is controlled by a
motor connected to a computer
Background In the last century most of the
research efforts by soil scientists and hydrologists
have focused on the vadose zone and on the
groundwater region, respectively. Mostly the impact
of the transition zone, the capillary fringe,
has been ignored. The thickness of this zone depends
on the properties of the respective soil, particularly
on the pore space and on the surface
roughness of the sand grains. With this experiment
we investigate the influence of a periodically
changing water table on size and shape of the capillary
fringe.
Methods and results To measure the water
content that is needed to determine the height of
the capillary fringe we use a Hele-Shaw cell that
consists of two parallel 50 × 30 cm 2 glass plates
with a 3 mm gap filled with homogeneous sand.
At the bottom, the cell is connected to a movable
water reservoir. We use the Light Transmission
Method (LTM) that is based on the fact that
the intensity of transmitted light can be used as a
proxy of water content. The calibration of LTM
with respect to water saturation is done by simultaneous
measurements of X-ray and light transmission.
A digital camera takes interval photos
during the whole experiment. By subtracting the
dry sand image from all images we get a normalized
image time series which represents the water
content in our sand column. In the first experimental
series we measure the dynamics of water
saturation for different water table. We chose different
amplitudes and frequencies for the water table
change. By analysing the first experiments we
found that in the experiments with high frequencies
(period of one hour) the system never reaches
equilibrium. In experiments with lower frequencies
(period of 24 hours) the state of equilibrium
during the first imbibition process is reached after
some hours. Subsequent cycles show a much
faster equilibration.
Outlook Interpreting the results of this experiment
is one part of the future work. This encompasses
the study of limiting cycles as well as the
nonlinear damping characteristics of the capillary
fringe. Moreover we are going to do some similar
experiments with changing parameters. For instance
we will use different velocities of the water
table change by slow or fast drainage and imbibition.
Another parameter to change is the surface
roughness of the sand grains. Different kinds of
sand might have different impact on the shape of
the capillary fringe.

100 CHAPTER 3. TERRESTRIAL SYSTEMS
3.1.4 Extension of the Grenzhof test site for conducting hydrogeophysical
investigations of water flow and solute transport at the field scale
Ute Wollschläger
Abstract At the Grenzhof test site hydrogeophysical methods are applied in combination with
classical soil physical techniques to estimate field-scale water flow and solute transport processes.
Recently the test site was extended to a 10 m × 300 m sized area to apply ground-penetrating radar
and electrical resistivity measurements at a scale of several hundreds of meters.
[ ns]
time
l
e
trav
0
10
20
30
40
50
distance [m]
0 50 100 150 200
0 50 100 150 200
Figure 3.4: Test site Grenzhof (left), electrical resistivity profile (upper right), and radargram (lower
right). Note that the measurements were not conducted along the same survey line.
.
Background A quantitative estimation of water
flow and solute transport at the field scale
is still a challenge. The heterogeneous structure
of most soils usually requires excavation of soil
profiles and intensive sampling of water content
and/or solute concentrations that cannot easily
be done at scales larger than a few meters. Hydrogeophysical
methods like ground-penetrating
radar (GPR), time-domain reflectometry (TDR)
and electrical resistivity tomography (ERT) are
non-invasive methods that provide measurements
of the dielectric and electric structure of soils.
These can be used as proxy variables to estimate
profiles of water content and solute concentrations,
respectively. These methods have the potential
to provide a data basis that allows quantitative
investigation and modeling of water flow
and solute transport over larger areas (i.e. a few
hundreds of meters) than those covered by classical
methods.
Funding Land Baden–Württemberg
Methods and results So far, water flow and
solute transport processes were investigated at the
Grenzhof test site from time series of TDR and
GPR measurements at a 10 m × 25 m sized area.
Particularly GPR measurements showed that the
method is well suited to measure and monitor
the dynamics of soil water content, whereas monitoring
of a salt tracer only provided information
about the position of the ”backend” of the tracer
pulse due to attenuation of the GPR signal caused
by high electrical conductivity of the tracer.
Recently, the site was extended to 10 m × 300 m.
In addition to the conventional GPR investigations,
multi-channel GPR surveys are conducted
that provide two-point common-midpoint measurements
and therefore allow simultaneous profiling
of reflector depth and water content over large
areas. As a new method ERT is applied that allows
monitoring of a salt tracer under conditions
where GPR signals are attenuated.
Outlook/Future work Time series of GPR–
and ERT–measurements will be taken to noninvasively
measure and monitor the dynamics of
soil water content and the movement of conservative
salt tracers. The joint application of these
complementary methods is expected to allow the
investigation of tracer movement even at conditions
where GPR fails due to high electrical conductivity
of the tracer solution. The data will
be used as basis to model water flow and solute
transport processes at the field scale.

3.1. SOIL PHYSICS 101
3.1.5 Installation of three soil and weather monitoring stations in permafrost
soils on the Qinghai–Tibet Plateau
Philip Schiwek
Abstract The high altitude permafrost on the Qinghai–Tibet Plateau exists under climatic conditions
that are quite different from those of permafrost in the arctic (strong radiation, pronounced
daily temperature cycles). The stations were installed to explore the thermal dynamics of the Plateau
permafrost. For this purpose the station measure meteorological data, soil temperature and soil water
content.
Background Under the current warming climate
permafrost is retreating almost worldwide.
On the Qinghai–Tibet Plateau the degeneration
of permafrost in the last decades caused desertification.
Lakes disappeared and the runoff of
catchments for rivers, that have their source on
the plateau, decreased. This is of course important
for the Tibetan people, who live as farmers
in this area. But it is also a major problem
for the water supply for the rest of China. Another
problem is, that through desertification on
the Plateau more dust storms could develop. The
degeneration of permafrost changes the mechanical
stability of the ground and thawing of massive
ice layers and lenses lead to vertical movement of
the soil. Those are major problems concerning the
construction of roads and railways on the Plateau.
Except of the very high mountain ranges, permafrost
in the Qinghai–Tibet area is classified as
a warm permafrost. So the assumption can be
made, that it reacts fast on climate changes. It
is hopped that this is monitored by the stations,
that should operate over several years.
With the analyses of the thermal and hydraulic
dynamics and with their quantification, more insight
could be achieved how the heat energy exchange
between the atmosphere and the soil develops
under changing climate conditions. For
instance could a higher precipitation in summer
bring more energy through the warm water into
the ground. It could change the albedo of the
ground and energy is removed from the ground
due to higher evaporation. In such cases it is not
easy to estimate, what the dominating factors are.
Funding DFG project: Ro 1080/10-2
Figure 3.5: Each of the soil–weather stations
measures meteorological data, soil temperature
and liquid soil water content of the active layer
in several depth down to the permafrost table.
Methods and results To study the thermal
dynamics of the Qinghai–Tibet Plateau permafrost
three soil– and weather–monitoring stations
were built in Qinghai province. The stations
measure air temperature, wind speed and wind
direction, precipitation, snow hight, net radiation
and air pressure. Those are the parameters, that
control the system from the surface. Also the soil
temperature and the liquid water content of the
active layer are measured in several depth. The
Sensors were installed in the ground down to the
depth of the permafrost table. Liquid water content
is measured with TDR. Ice content or vapour
could not be measured. The data are measured
and stored every hour. At two stations temperature
of the deeper permafrost can be derived from
nearby boreholes.
At the site Cumarhe (35 ◦ 10.72’N 93 ◦ 57.21’E
4443 m) permafrost lies at a depth of 2.4 m,
groundwater at 1.3 m depth. The site is located on
an alluvial fan, the soil consists of rather coarse
sediments. At Qumahe (34 ◦ 54.23’N 94 ◦ 47.42’E
4447 m) the station is built on a peat soil with
high organic content and fine sediments and a permafrost
table at 1.36 m depth. The vegetation
here is very strong. At Zuimatan (35 ◦ 21.47’N
99 ◦ 08.37’E 4187 m) sediments are again coarser
and vegetation is weak. The permafrost table lies
at 2.65 m depth, groundwater at 2.05 m. The site
is characterised by a high salinity of the groundwater.
At two stations measurements with Ground
Penetrating Radar were made.
Outlook/Future work The data will be read
out every three month. With this data analysis for
thermal and hydraulics dynamics will be made.

102 CHAPTER 3. TERRESTRIAL SYSTEMS
3.1.6 Investigation on the applicability of remote sensing in surface moisture
studies
Carolin Ulbrich
Abstract There is no doubt about the importance of surface soil moisture determination. However
due to its variation within a few meters one has to carefully watch the scale of measurement. We want
to bridge the gap between the scale of the common measurements of up to a few meters and the large
scale of the planned SMOS-mission that will be 30 km. Therefor we perform a preliminary study on
satellite-born radar data with a 30 m resolution aimed at determining the applicability of such data
in surface soil moisture studies.
Mannheim
Ludwigshafen
Heidelberg
GPR
1 m
30 km 10 m
Background The scale of measurement is crucial
to soil moisture determination (see Figure
3.6).
To investigate preferential flow, contaminants and
ground water quality small in-situ probes can be
used. Convenient are for example TDR probes or
capacitance measurements for volumes of about
1 dm 3 . These measurements are exact but not applicable
on larger scales. Data from such moisture
probes can lead to essential errors when trying to
extract field information from them because they
cannot be installed in an arbitrary quantity (work
intensive, expensive, time scale). However there
are soils that have a variability in soil moisture
reaching from dry to saturated within a few meters.
Arctic tundra is an example.
Ground penetrating radar (GPR) provides a tool
that may be used to perform measurements on
the field-scale. The velocity of the emitted electromagnetic
wave is affected by soil moisture. A
resolution of about 1 m for surface moisture can
be obtained on a scale of hundreds of meters.
At the largest scales, air and space born radar
can be used to determine surface soil moisture.
In active measurements the backscattered radar
pulse is recorded, passive measurements address
brightness temperature. The area information is
needed for example in coupled land-atmosphere
models and meteorology. Resolution ranges from
a few meters for airplane measurements and 30 m
for the active radar satellites ERS2 and Envisat to
30 km for the upcoming passive radar instrument
SMOS.
Funding Land Baden-Württemberg, data provided
by the European Space Agency
Figure 3.6: The resolution of the available surface
moisture measurement tools varies between
less then 1 m, typical for ground radar (GPR),
at least 10 m for active radar satellites and over
30 km for the passive radar satellite SMOS.
Methods and results In this preliminary
study data from the satellite Envisat were analyzed.
The test areas include the Grenzhof site,
near Heidelberg, as well as some sites in China.
Due to the low spatial resolution of about 30 m
and the heterogenous vegetation of the fields at
the Grenzhof we will probably not apply the
method to this test site. An air plane active or
passive radar time series would be ideal to investigate
the up-scaling of soil moisture data that are
measured with GPR on the 1 m-scale to the satellite
scale in such heterogeneous regions.
Some test sites in China are characterized by large
and homogenous bare soil planes which makes the
interpretation of soil moisture satellite data much
more reliable. Unfortunately it will not be possible
to obtain a dense GPR time series of these
regions.
The interpretation of backscatter radar data requires
detailed auxiliary information about the
soil surface on a km-scale. This could be avoided
in a long time series making use of interferometry.
A great opportunity to determine surface soil
moisture that requires no detailed knowledge of
the surface is provided by the Japanese satellite
ALOS. Its radar device is capable of measuring
radar data multipolarized. Soil moisture can then
be extracted directly from the data. Two acquisitions
in this mode are planned in 2007. The
Canadian Radarsat2 will offer similar opportunities
(launch planned for 2007).
Outlook/Future work From the ALOS data
surface information can be extracted and used to
interpret the available ESA data. We hope to be
able to draw a line from the operating satellites to
the SMOS satellite that is planned to be launched
in 2007 and will compare these data sets to ground
measurements.

3.1. SOIL PHYSICS 103
3.1.7 Simulation of Ground Penetrating Radar Measurements over Multi-
Layered Materials using a Plane Wave Approach
Holger Gerhards
Abstract A plane wave approach adapted from optical applications for graded index models is used
for predicting ground penetrating radar measurements over smoothly changing dielectric properties,
which are used as proxies for soil water content and salt concentration.
(a) (b)
amplitude (scaled) [-]
-0.3 -0.2 -0.1 0 0.1 0.2 0.3
rel. diel. permittivity
0 10 20
0
Figure 3.7: (a) Modeled radiation of the GPR system. (b) Permittivity profile and reflected electromagnetic
signal from a discrete permittivity jump and a capillary fringe in a coarse (grey line) and a
fine textured (black line) soil.
Background Ground penetrating radar (GPR)
is a widely used method for qualitative and quantitative
studies for non-invasive investigations of
different materials and for the remote detection of
buried objects. The significant difference between
the dielectric permittivity of soil and water make
GPR also attractive for applications in hydrological
sciences. These applications are confronted
with smooth transitions in dielectric properties,
caused by gradual textural changes, by capillary
fringes above water tables, or by solute pulses.
Because of all these effects the evaluation of measured
GPR data is nontrivial. Although tools of
numerical forward modeling or recent inversion
techniques are available, a lot of evaluation procedures
are based on ray approach estimations extracted
from the phase information of the measured
signals. The reason for this is the very high
computational cost of the numerical methods.
Funding DFG project: Ro 1080 / 10-2
Methods and results A plane wave approach
for an arbitrary horizontal layered medium,
adapted from optical theory, was set up. It
uses the propagation of the electric and magnetic
field components within a homogeneous medium,
which are continuous at boundaries. This propagation
can be represented mathematically by matrices,
which can be multiplied iteratively. The
time [ns]
0
20
40
60
x10
general reflection coefficient is a function of the
components of the global transition (propagation)
matrix. With this approach GPR signals can be
predicted by applying an adequate frequency and
angle spectrum to simulate the radiation of the
emitted GPR pulse (Fig. 3.7).
It was demonstrate that smooth transitions
lead to reflections with low amplitude but with
a specific signature (Fig. 3.7). Apparently, transitions
from lower to higher permittivities (water
contents) act as low-pass filters and lead to
a broadening of the reflected wavelet.
Furthermore, our simulations show, that the
travel time of the largest wavelet extremum leads
to a good matching depth for the upper end of the
capillary fringe or the maximum of a conductivity
pulse.
Outlook/Future work Simple experiments
will be conducted to analyze GPR reflected data
from gradual changes of water content and conductivity.
They will be compared with the simulations.
This allows to assess the contribution of
near field effects which are not accounted for in
the plane wave approach.
Main publications H.Gerhards, F.Lederer,
K.Roth: Simulations of Ground Penetrating
Radar Reflections from Gradual Changes of Dielectric
Properties, Geophysics, submitted
depth [m]
0.5
1.0
1.5
2.0
2.5
3.0

104 CHAPTER 3. TERRESTRIAL SYSTEMS
References
Braun, H. 2006. A new hypothesis for the 1470-year cycle of abrupt warming events in the last ice-age.
PhD Thesis, Universität Heidelberg.
Leidenberger, P., Oswald, B., & Roth, K. 2006. Efficient reconstruction of dispersive dielectric profiles
using time domain reflectrometry (TDR). Hydrol. Earth Syst. Sci., 10, 209–232.
Rezanezhad, F, Vogel, H.-J., & Roth, K. 2006. Experimental study of fingered flow through initially
dry sand. Hydrol. Earth Syst. Sci. Discuss., 3, 2595–2620.
Schneider, Klaus. 2005. Novel evaporation experiment to determine soil hydraulic properties. diploma
thesis, Universität Heidelberg.
Schneider, Klaus, Ippisch, Olaf, & Roth, Kurt. 2006. Novel evaporation experiment to determine soil
hydraulic properties. 10, 817–827.

3.2. ICE AND CLIMATE 105
3.2 Ice and Climate
Dietmar Wagenbach
Group members
Thomas Gölzhäuser, diploma student
Felix Jahn, diploma student
Dipl. Phys. C. Offermann
Dipl. Phys. B. May, PhD student
Dipl. Phys. M. Pettinger, PhD student
Dipl. Phys. M. Schock, PhD student
D. Wagenbach, head of group
Figure 3.8: Drilling camp at Colle Gnifetti (Monte Rosa 4500 m a.s.l.). From left to right: drill shelter,
Zumsteinspitze and Dufour Spitze (4634 m a.s.l.). Picture: Olaf Eisen
Main methods and specific objectives Among all paleo-archives, only non-temperated glaciers
basically allow the reconstruction of climate as well as of environmental records. Appropriate ice core
studies may thus allow to tackle the crucial problem about the mutual relationships between changes
of climate and bio-geochemical cycles through a retrospective approach. In this context, the ’Ice and
Climate’ group concentrates on ice core investigations by deploying the following species, backed up
by standard physical ice properties:
• water-isotopomeres δ 18 O-δD (thermometry)
• various particulate key species as mineral dust, major ions, organic carbon (bio-geochemical
cycles),
• natural radionuclides as terrestrial 210 Pb, cosmogenic 10 Be, 3 H, 36 Cl (solar variability) and on
3 He, 4 He isotopes (basal layer dynamics).
Apart from joint activities within polar ice core studies [EPICA Community Members, 2006], emphasis
is thereby on the selfcontained exploration of non-temperated Alpine glaciers. Such small scale drill
sites are unique in supplementing high latitude ice core findings, though reliable atmospheric signals
would be much more difficult to elucidate here [Preunkert et al. , 2000]. In addition to ice core
analyses, deserving application of novel techniques [Preunkert & Wagenbach, 1998] and species [Ruth
et al. , 2003], also process-oriented field studies are regularly performed. These activities are aimed at
understanding the transfer of the atmospheric signals into the glacier archive as well as at constraining
their basic glaciological embedding conditions (as e.g. controlled by the near surface and near bed-rock
glacier dynamics). Based on external collaborations, dedicated atmospheric observations are deployed
here at various Alpine and Antarctic sites [Wagenbach et al. [1998], Piel et al. [2006]], which also
include isotopic fingerprints of aerosol samples ( 15 N, 14 C, 10 Be). Within the glaciological issue, joint
efforts range from ground penetrating radar soundings of the internal stratigraphy in Alpine glaciers

106 CHAPTER 3. TERRESTRIAL SYSTEMS
[Eisen et al. , 2003] and related glacio-meterological and glacio-chemical surveys, to the prospection
of novel ice core species ( 3 He/ 4 He [Friedrich, 2003]) and dating techniques as 14 C in organic matter
or 26 Al/ 10 Be).
Overview on principal activities and achievements
Alpine research
a) EU ALP-IMP related: Regular ice core analyses started on the new KCI core (Colle Gnifetti, Monte
Rosa), which was drilled to bed rock in collaboration with KUP (University Bern) and the Geographical
Institute of University Zürich. Thereby, the basic stratigraphy (dust, total ion content, ice conductivity)
could be investigated at sub-cm depth resolution via continuous flow analyses over 50 %
of the total depth. Additional profilings down to bedrock were finished for stable water isotopes in
coarse resolution and, in collaboration with AWI, for high resolution scanning of the core density
and optical transparency. From these analyses it became evident, that the core: (1) indeed offers an
uniquely low accumulation rate (comparable to the lowest one in North Greenland), which, different
to all other cores shows increase in the up stream area; (2) did not reach the very ice rock interface
due to a blocking boulder. Nevertheless we may expect from the bottom part of the KCI core records
with a higher time resolution, than hitherto obtained from other Alpine cores.
b) EU CARBOSOL related: Evaluation of the IUP contribution demonstrated the invaluable potential
of the radioisotopes 210 Pb and radiocarbon in the interpretation of the spatio-temporal changes
observed in the CARBOSOL aerosol network. Here, 210 Pb was shown to help in distinguishing transport
from source related variations [Hammer et al. , submitted]. Radiocarbon allowed to quantify the
fossil fraction of the organic aerosol over different clean air and polluted areas, as forming the base for
estimating the source apportionment of secondary organic aerosol. Also related to the anthropogenic
impact on the European clean air aerosol, first DOC records from Alpine ice core were used to infer
the long term change of the organic aerosol load [Legrand et al. , submitted].
Antarctica
a) ESF EPICA related: Sampling dedicated to He-isotope analyses of the bottom Antartic EDML
core could be accomplished at at the deep drilling site, though the very basal layer could not be
sampled due to the surprising occurrence of liquid water at the ice bedrock interface. Mass spectrometric
analyses of these samples and the Antarctic EPICA Dome C He-Profile could be almost
finished by the IUP ’Groundwater and Paleoclimate’ group. They show a significant abundance of
crustal He till some 100 m above bedrock, which is not understood yet, but already seen in our former
He-measurements from the deep Greenland (GRIP) ice core. Ongoing He-analyses will complete the
available profil from the Greenland NGRIP core, thus providing a further profil close to bedrock.
Aimed at the investigation of the air firn transfer of atmospheric aerosol species in Antarctica [Weller
& Wagenbach, submitted] the first comprehensive atmospheric aerosol records could be obtained year
round from an central Antarctic position (in collaboration with AWI). These observation from the
EDM drill site (completing the ongoing recordings at the coastal overwintering station Neumayer)
may now constitute the base for dedicated investigations into the air/firn transfer at the EDML drill
site.
Activities envisaged in the following year
• Englacial temperature profiling of the KCI borehole (jointly with University Zürich)
• Laboratory experiments, simulating the He (Ne) outgassing prosses of glacier ice at various
texture properties.
• Investigation of cave ice in the ’Eisriesenwelt’ aimed at estimating its age and mass balance
• Drilling through Piz Murtel (Engadine) postponed to winter 2006 (jointly with University Zürich
and KUP University Bern)
• Investigation of the dielectric properties of glacier ice with Soil Physics Group and AWI (O.
Eisen)
• Ongoing re-designing of the Air Chemistry Observatory at the Antarctic Neumayer Station III
(with AWI and the Carbon Cycle Group)

3.2. ICE AND CLIMATE 107
Funding
• EU ALP-IMP (Multi-centennial climate variability in the Alps based on instrumental data,
model simulations and proxy data)
• AWI-Cooperation contract (Investigation of ice cores and aerosol of polar regions)
• Austrian Research Fund project of VERA ( 26 Al- 10 Be investigations)
• Austrian Academie project (AUSTRO*ICE*CAVE*2100) jointly with the Institut für Geologie
und Paläontologie, University of Innsbruck
Important logistical support was obtained from the ESF-EU core project EPICA (European Ice
Drilling in Antarctica)
Major cooperations
• Alfred Wegener Institute for Polar and Marine Research (AWI) (various polar investigations)
• Laboratoire de Glaciologique et Geophisique-CRNS, Grenoble (LGGE) (Alpine ice cores and
Lake Vostok)
• Geographical Institute of the University Zürich (Alpine glaciology and glacio-meteorology)
• Klima und Umweltphysik, University Bern (ice core drilling and analyses)
• VERA-laboratory, Institut für Isotopenforschung und Kernphysik der Universität Wien (VERA)
(AMS-analyses)
• Institute for Zoology and Limnology, University Innsbruck (ice biology and high Alpine lake
sediments)
• Institut für Geologie und Paläontologie, University of Innsbruck (cave ice research)
• ZentralAnstalt für Meteorologie und Geodynamik, Vienna (Alpine climatology) (ZAMG)
• British Antarctic Survey, Cambridge (Berkner Island Project)
• Institute for Environmental Geochemistry, University Heidelberg (trace element analyses)
Internal collaborations concern, mainly the Neumayer Observatory, 14 C and radon investigations
(Carbon Cycle Group), noble gas and tritium analyses (Groundwater and Paleoclimate Group), long
term marine 10 Be sediment records (Heidelberger Academy of Sciences) and newly established the
investigation of the dielectric glacier ice properties (Soil Physics Group).
Peer Reviewed Publications
1. Bigler et al. [2006]
2. EPICA Community Members [2006]
3. Piel et al. [2006]
4. Steier et al. [2006]
5. Wolff et al. [2006]
6. Auer et al. [in pressb]
Other Publications
Pettinger et al. [2006]
Diploma Theses
Jahn [2006]

108 CHAPTER 3. TERRESTRIAL SYSTEMS
3.2.1 Radiocarbon measurement in ice
Barbara May (participating scientists: Dietmar Wagenbach and Peter Steier (VERA))
Abstract A sample preparation line for 14 C analysis of organic matter in ice by AMS is under
construction. Preliminary investigations show, that the blank mass should be lower than 10 µgC.
First analyses revealed DOC concentrations in ice of 140 to 560 µgC/kg and POC concentrations in
snow as low as (64 ± 18) µgC/kg.
Figure 3.9: Relative error of the measured 14 C concentration (in pmC) for a sample mass of 100 µgC
and for three different procedure blank masses. Also shown are the corresponding sample ages and
age errors in ka (note the non linear relationship with pmC).
Background While polar glaciers and ice
sheets can be basically dated into the last glacial
by annual layer counting and reference horizons,
these standard dating tools are not applicable to
’exotic’ ice archives, like small mountain glaciers,
cave ice or ice wedges. Thus, to extend the domain
of long term ice records to non-polar regions
and to explore other promising ice archives, 14 Canalysis
of organic matter is expected to be the
only reliable dating tool, provided that the organic
carbon entrapped in glacier bodies is representative
for the deposition age. However the small
and variable carbon mass and the distinction between
different carbon fractions (POC and DOC)
make thorough experimental efforts necessary to
achieve reliable 14 C results.
Method The organic carbon fractions can be
divided into POC (particulate organic carbon)
and DOC (dissolved organic carbon). For the extraction
of these carbon fractions, two set-ups will
be designed:
1. a POC filtration system allowing for an efficient
extraction of large as well as very small
amounts of organic matter from various ice
samples
2. a DOC extraction system, where dissolved
organic matter is converted to CO2 by UVoxidation,
which is then extracted by degassing
Large POC samples will then be combusted in the
CARMEN system in an oxygen stream, smaller
ones in quartz-glass vials with CuO. Designated
analyses have shown, that the CARMEN system
blank for stream combustion can be reduced to
less than (35 ± 10) µgC. All CO2 samples will be
cleaned and quantified in the extraction part of
the CARMEN system, which has a blank of only
a few µgC.
The dating of small ice samples with little carbon
content needs a small blank-to-sample-mass ratio.
As the sample mass is limited and should be kept
as low as possible to obtain a reasonable time resolution,
the procedure blank has to be strongly
minimized to allow reliable radiocarbon dating.
As seen in Figure 3.9 the blank mass should be
less than 10 µgC.
Pilot studies Steier et al. [2006] reports preindustrial
POC concentrations from the ’Grenzgletscher’
between 24 and 370 µgC/kg. Analyses
of two miniature ice caps in the Swiss Alps (Piz
Murtel and Lischana) for DOC and POC revealed,
that DOC concentrations ranged here between
140 µgC/kg for ’clean’ ice and 560 µgC/kg for
strong dust layers. The POC content of the samples
is not determined yet, but a first estimate
gives concentrations for strong dust layers of up
to at least 20 mgC per kg ice. An analysis of snow
from the high Alpine Colle Gnifetti gives a POC
content of less than (64 ± 18) µgC per kg snow.

3.2. ICE AND CLIMATE 109
3.2.2 Climate significance of stable water isotope records from Alpine ice
cores.
Markus Pettinger (participating scientists: Dietmar Wagenbach, Felix Jahn, Susanne Preunkert
(LGGE) and Reinhard Böhm (ZAMG))
Abstract We report on the isotope record obtained from a new ice core drilled in the Monte Rosa region,
backed up by investigations related to the upstream effect. Recent warming trends are addressed
in view of the apparent isotope temperature relationship.
T [°C]
δ 18 O [‰]
δ 18 O [‰]
-11
-12
-13
-14
-15 -8
-10
-12
-14
-16
-8
-10
-12
-14
-16
Annual precipitation Temperatures
KCI ice core
Monte Rosa stacked
2000 1980 1960 1940 1920 1900
Year A.D.
Figure 3.10: δ 18 O - records of the new Monte Rosa
ice core (KCI) compared to a stacked data of three
ice cores from the western flow line and to instrumental
annual time series precipitation weighted
temperature compilations.
Background Isotope δ 18 O and δD records from
high Alpine cold glaciers provide complementary
records to polar cores, including the unique possibility
to extend the 250 years instrumental climate
time series only available for the Greater Alpine
Region [Auer et al. , in pressa]. To minimize the
influence of glaciological ’noise’ on the interpretation
of the isotopic record in terms of temperature
changes there, a multicore study was set up. Also
the evaluation of upstream and local meteorological
effects on the isotope record is mandatory.
Methods and results In autumn 2005 a new
ice core (KCI) from Colle Gnifetti (Monte Rosa
summit region) completing the existing array of
down to bedrock ice cores was recovered and
analysed for its coarse isotope stratigraphy. The
drilling position was carefully determined using
a grid of GPR (Ground Penetrating Radar) mea-
surements [Böhlert, 2005] with respect to minimal
accumulation rate, flat bedrock and well defined
catchment area. The expectedly low accumulation
was confirmed to 14.8 m w.e./a by the tritium
bomb peak horizon, dating of the core was
confirmed according to [Jahn, 2006].
Investigation of the δ 18 O upstream effects along
the KCI - flow line revealed a twofold upstream
increase of the accumulation rate associated with
a systematic isotope shift. This effect is expected
to influence the KCI core section below 20 m w.e.
(i.e. before 1800 A.D.).
In the KCI core, the overall δ 18 O trend in the 20 th
century exhibits a rise of 2.3 � corresponding to a
change in temperature of 1.2 ◦ C. This suggests an
apparent isotope sensitivity of 1.8 �/ ◦ C, much
higher as commonly expected. Also the recent
warming trend from the 80ies to 2004 is recorded
and yields by 2.5 � and 1.4 ◦ C, respectively.
Seasonal isotope data from fresh snow samples
collected at high Alpine locations (Signalkuppe,
Klein Matterhorn and Sonnblick) reveal no peculiarities
in the δ 18 O/δT - relation with respect to
the values found for low level stations of the GNIP
database (about 0.6 �/ ◦ C).
Within the multicore approach the KCI ice core
record appears to be well suited to complement
the instrumental temperature time series regarding
long term climate changes.
Outlook/Future work Improved dating of the
new Monte Rosa ice core (along with a Dôme du
Goûter core from Mont Blanc) over the instrumental
period.
Funding EU-project ALP-IMP (Multicentennial
climate variability in the Alps based on
Instrumental data, Model simulations and Proxy
data)
Main publications [Pettinger et al. , 2006]

110 CHAPTER 3. TERRESTRIAL SYSTEMS
3.2.3 Dissolved organic carbon (DOC) in glaciers: recent temporal changes
and natural levels
Martin Schock (participating scientists: Patrik Heiler, Dietmar Wagenbach, Michel Legrand (LGGE),
Susanne Preunkert (LGGE), Jean-Robert Petit (LGGE))
Abstract Deploying a highly sensitive DOC analysis method on high Alpine ice cores, the recent
changes in the organic aerosol load was investigated.
Figure 3.11: DOC in two Mont Blanc ice cores at sub-seasonal and multi-year time resolution. No data,
except from snow pits, are available from very recent times due to the impossibility to decontaminate
porous firn cores
Background The bulk quantity DOC constitutes
an important part of the impurity content
of non-temperated glaciers. Related retrospective
studies would be highly relevant therefore in terms
of radiative forcing, past atmospheric carbon cycles
and englacial microbial activity. However, no
systematic ice core analyses of DOC were available,
yet, due to unsolved contamination problems
and the insufficient sensitivity of conventional
analysers.
Methods and results Based on UV induced
DOC oxidation, a continuous, sub-seasonal DOC
ice core record could be established from Col du
Dome back into the pre-industrial era, and supplemented
by results of various organic species (obtained
within CARBOSOL) from proximate and
distal Alpine cores. Thereby the 2-4 fold overall
increase of DOC is found to be much lower
than those of black carbon or sulphate. Also different
to these species is the DOC change, which
is not entirely related to radiatively active particles
and cannot not exclusively attributed to anthropogenic
emissions. However, comparison with
other carbonaceous components (carboxylic acids,
HULIS, etc.) suggest that ice core DOC may be
eventually used as proxy for the secondary organic
aerosol load. This fraction produced from, mainly
biogenic, gaseous precursors may have been indirectly
increased through anthropogenic change of
the atmospheric oxidative capacity.
In addition, ongoing DOC analyses of accreted ice
from Lake Vostok (Antarctica) confirmed previous
results, suggesting a DOC level in the range
of some ng/g, which would strongly limit viable
micro biological activities within the lake. To corroborate
this finding, the efficiencies of UV versus
high temperature based DOC oxidation methods
were thoroughly compared using high Alpine
lake ice, providing, however, conflicting results of
higher UV based yields.
Outlook/Future work Quantification of the
UV oxidation yield and recent DOC trends in
Greenland ice cores.
Funding EU CARBOSOL project: ’Present
and Retrospective State of Organic versus Inorganic
Aerosol over Europe : Implications for Climate’
Main publications Legrand et al. [submitted]

3.2. ICE AND CLIMATE 111
3.2.4 Progress in developing novel tools for Antarctic ice core research
Dietmar Wagenbach (participating scientists: Rolf Weller (AWI) and Matthias Auer (VERA))
Abstract Progress achieved in automatic central Antarctica aerosol sampling and in the prospecting
of the 26 Al/ 10 Be dating tool are reported and assessed.
Figure 3.12: Seasonal cycle of total nitrate in central Antarctica obtained by automatic aerosol samplings
(left), overall changes of mean 26 Al/ 10 Be ratios seen in Antarctic (Neumayer), alpine (Sonnblick)
and upper troposphere aerosol as well as in Antarctic snow from Dome C (right).
Background See also Annual IUP Report 2005.
a) Automatic sampling: Interpretation of Antarctic
ice core records of aerosol species needs considering
year round atmospheric records, which
were not available however from inland positions.
Therefore IUP developed an autonomous aerosol
sampling device (ROBERTA) to be deployed year
round at the EPICA-DML drill site in the Atlantic
sector of east Antarctica.
b) 26 Al: Also the essentially unknown age and
stratigraphical feature of the basal core sections
challenge experimental dating tools to be deployed
here. In close collaboration with the University
of Vienna the dating deficit of very old ice
samples has been tackled therefore by exploring
the feasibility of the 26 Al/ 10 Be ratio (apparent
T 1/2 = 1.310 −6 a) as a radiometric chronometer.
Progress report
a) Deploying an improved sampler version, year
round, unattended running of the aerosol sampling
system at the EDML drill site could be successfully
maintained in 2005, indicating, that the
polar night energy problem became almost settled.
Evaluation of the first comprehensive observations
on the seasonal change of major ion
revealed, relative to coastal records: important
phase shifts of species with marine sources, but
a close agreement of nitrate cycles [Weller & Wagenbach,
submitted]. This surprising coherence
may need revisiting the open question of the major
Antarctic nitrate source.
b) In extending our former 26 Al/ 10 Be analyses
to Antarctic surface snow and high tropospheric
samples and in gaining first 53 Mn results from
Antarctic aerosol we got following evidences for
the 26 Al dating potential: (1) the overall (short
term) 26 Al / 10 Be variability in various recent
snow aerosol samples is less than 6 %. This figure
would translate into a dating uncertainty of
around 100 ky, indicating as well a negligible influence
of terrestical 26 Al. (2) interplanetary dust
(IPD) appears to contribute to the atmospheric
26 Al budget of Antarctica by some % only. This
results is, however, still to be confirmed by respective
firn analyses, needing to process some 100kg
of surface snow.
Future work
a) Adding results from ongoing 2006 samplings,
glacio-meteorological and snow pit data, the
source pattern and governing air/firn deposition
processes will be elucidated for the DML drill site
realm.
b) Backed up by surface snow 53 Mn first
26 Al/ 10 Be analyses are envisaged for the basal section
of Antarctic ice cores, perhaps including some
Ma old ground ice from the Dry Valleys.
Funding
a) AWI-Cooperation Contract
b) joint Austrian Research Fund (FWF) project
among VERA and IUP
Main publications a) [Weller & Wagenbach,
submitted], b) [Auer et al. , in pressb]

112 CHAPTER 3. TERRESTRIAL SYSTEMS
References
Auer, I., Böhm, R., Jurkovic, A., Lipa, W., Orlik, A., Potzmann, R., Schöner, W., Ungersböck, M.,
Matulla, C., Brunetti, M., Nanni, T., Maugeri, M., Mercalli, L., Briffa, K., Jones, P., Efthymiadis,
D., Mestre, O., Moisselin, J.M., Begert, M., Müller-Westermeier, G., Kveton, V., Bochnicek, O.,
Stastny, P., Lapin, M., Nieplova, E., Cegnar, T., Dolinar, M., Gajic-Capka, M., Zaninovic, K., Majstorovic,
Z., Szalai, S., & Szentimrey, T. in pressa. HISTALP Historical instrumental climatological
surface time series of the Greater Alpine Region. International Journal of Climatology.
Auer, M., Kutschera, W., Priller, A., Wagenbach, D., Wallner, A., & Wild, E. M. in pressb. Atmospheric
26 Al and 10 Be as a dating tool for climate archives. Nuclear Instruments and Methods
B.
Bigler, M., Rthlisberger, R., Lambert, F., Stocker, T.F., & Wagenbach, D. 2006. Aerosol deposited
in East Antarctica over the last glacial cycle: Detailed apportionment of continental and sea-salt
contributions. Journal of Geophysical Research, 111, (8)(D08205).
Böhlert, R. 2005. Diplomarbeit, Institut für Geographie, Universität Zürich.
Eisen, O., Nixdorf, U., Keck, L., & Wagenbach, D. 2003. Alpine Ice Cores and Ground Penetrating
Radar: Combined Investigations for Glaciological and Climatic Interpretations of a Cold Alpine Ice
Body. Tellus, 55B (5), 1007–1017.
EPICA Community Members. 2006. One-to-one coupling of glacial climate variability in Greenland
and Antarctica. Nature, 444(195).
Friedrich, R. 2003. Helium in polaren Eisschilden. Diplomarbeit, Instiut für Umweltphysik, Universität
Heidelberg.
Hammer, S., Wagenbach, D., Preunkert, S., Pio, C., Schlosser, C., & Meinhardt, F. submitted. 210 Pb
observations within CARBOSOL: a diagnostic tool for assessing the spatio-temporal variability of
related chemical aerosol species. Journal of Geophysical Research.
Jahn, F. 2006. Einsatz der Continous Flow Analysis zur vorläufigen Datierung eines alpinen Eiskerns.
diploma thesis, Universität Heidelberg.
Legrand, M., Preunkert, S., Schock, M., Cerqueira, M., Kasper-Giebl, A., Alfonso, J., Pio, C., Gelencser,
A., Etchevers, I., & Simpson, D. submitted. Major 20th century changes of organic aerosol
components (BC, WinOC, DOC, HULIS, mono and dicarboxylic acids and cellulose) derived from
Alpine ice cores. Journal of Geophysical Research.
Pettinger, M., Jahn, F., Wagenbach, D., Bhlert, R., Hoelzle, M., & Preunkert, S. 2006. Climate
significance of stable water isotope records from Alpine ice cores. Geophysical Research Abstracts,
Vol. 8, 09854. Poster.
Piel, C., Weller, R., M.Huke, & Wagenbach, D. 2006. Atmospheric methane sulfonate and non-sea
salt sulfate records at the EPICA deep-drilling site in Dronning Maud Land. Journal of Geophysical
Research.
Preunkert, S., & Wagenbach, D. 1998. An automatic recorder for air/firn transfer studies of chemical
aerosol species at remote glacier sites. Atmospheric Environment, 23, 4021–4030(10).
Preunkert, S., Wagenbach, D., Legrand, M., & Vincent, C. 2000. Col du Dome (Mont Blanc Massif,
French Alps) suitability for ice core studies in relation with past atmospheric chemistry over Europe.
Tellus, 52B (3), 993–1012.
Ruth, U., Wagenbach, D., Steffensen, J.P., & Bigler, M. 2003. Continuous record of microparticle
concentration and size distribution in the central Greenland NGRIP ice core during the last glacial
period. Journal of Geophysical Research, 108 (D3)(10.1029/2002JD002376).
Steier, P., Drosg, R., Fedi, M., Kutschera, W., Schock, M., Wagenbach, D., & Wild, E.M. 2006.
Radiocarbon determination of particulated organic carbon in non-temperated, alpine glacier ice.
Radiocarbon, 48(1), 69–82.
Wagenbach, D., Ducroz, F., Mulvaney, R., Keck, L., Minikin, A., Legrand, M., Hall, J. S., & Wolff,
E. W. 1998. Sea-salt aerosol in coastal Antarctic regions. Journal of Geophysical Research, 103
(D9)(10.1029/97JD01804), 10961–10974.

3.2. ICE AND CLIMATE 113
Weller, R., & Wagenbach, D. submitted. Year round chemical aerosol records in continental Antarctica
obtained by automatic samplings. Tellus.
Wolff, E.W., Fischer, H., Fundel, F., Ruth, U., Twarloh, B., Littot, G.C., Mulvaney, R., Röthlisberger,
R., De Angelis, M., Boutron, C.F., Hansson, M., Jonsell, U., Hutterli, M.A., Lambert, F., Kaufmann,
P., Stauffer, B., Stocker, T.F., Steffensen, J.P., Bigler, M., Siggaard-Andersen, M.L., Udisti,
R., Becagli, S., Castellano, E., Severi, M., Wagenbach, D., Barbante, C., Gabrielli, P., & Gaspari,
V. 2006. Southern Ocean sea-ice extent, productivity and iron flux over the past eight glacial cycles.
Nature, 440(7083), 491–496.

Aquatic Systems
4.1 Groundwater and Paleoclimate . . . . . . . . . . . . . . . . . . . . . . . . 118
4.2 Lake Research (Limnophysics) . . . . . . . . . . . . . . . . . . . . . . . . 131
115

Overview
Werner Aeschbach-Hertig
Summary
Research on aquatic systems at the IUP focusses mainly on freshwater environments, such as lakes and
groundwater, but also includes some special topics of marine systems, for example the geochemistry
of the deep brines in the Red Sea. A major motivation to investigate freshwater systems stems from
their fundamental importance as water resources, an issue that gains increasing importance in view of
the ever larger stress that human exploitation and interference exerts on these vital reserves. Another
increasingly important issue is the impact of climate change on the quantity, quality, and distribution
of water resources. These problems are particularly crucial for the arid and semi-arid parts of the
world, where we are therefore especially active.
Groundwaters also constitute an archive of past climate conditions, which we exploit by application of
the noble gas thermometer, stable isotopes, and radiocarbon dating. We also aim at extending these
methods of paleoclimate reconstruction from stored meteoric water of the past to new archives, in
particular the microscopic water inclusions in speleothems. In the most important archive of old water
- the polar ice sheets - the noble gas thermometer cannot be used, but noble gases in air inclusions in
the ice provide a potential source of information that hardly has been tapped so far.
The research in the aquatic systems division of the IUP may thus be divided in two main areas:
Physics of freshwater systems and paleoclimate reconstruction. The fundamental goal of the research
on aquatic systems is to obtain a better understanding of the physical processes that transport water,
energy, and dissolved substances within and between these systems. To this end we employ direct
measurements of physical parameters as wells as tracer and isotope methods. Examples of studied
processes are vertical turbulent mixing in stratified lakes, groundwater - lake exchange, and recharge
and flow rates in aquifers. The final goal of the paleoclimatic work is to obtain a quantitative knowledge
of the size and timing of past temperature change, in order to compare with recent trends and
help improving predictions for the future. At present we focus on the refinement of the noble gas
thermometer by improving our understanding of gas partitioning in groundwater and on the extension
of the method to new archives. Further details on this research can be found below in the reports of
the research groups in aquatic systems: ”Groundwater and Paleoclimate” and ”Limnophysics”.
Future work
After a first period of establishing itself, the aquatic systems division of the IUP is now expanding in
a variety of new ventures. Having established a modern noble gas lab, new applications are currently
starting up. Furthermore, new collaborations within the institute and the physics faculty in Heidelberg
are being pursued. In addition to the ongoing projects described in the individual reports below, the
most important perspectives for future projects are the following:
1. The potential of radon for studying groundwater-lake exchange is to be investigated more comprehensively
(DFG-proposal submitted).
2. A new groundwater project in India in collaboration with Dr. S.K. Gupta, Phyiscal Research
Laboratory, Ahmedabad is planned. A DFG-proposal will soon be submitted.
3. ATTA (atom trap trace analysis), a new method for ultra-sensitive detection of rare radioisotopes,
is being developped in collaboration with M. Oberthaler, KIP, Heidelberg
4. He and other noble gases in ice are investigated in collaboration with the ice group, IUP.
117

118 CHAPTER 4. AQUATIC SYSTEMS
4.1 Groundwater and Paleoclimate
Werner Aeschbach-Hertig
Names of group members
Prof. Werner Aeschbach-Hertig, head of group
Dr. Reinhold Bayer, administration
Dr. Laszlo Palcsu, postdoc
Dipl. Ing. Gerhard Zimmek, technician
Dipl. Phys. Ronny Friedrich, PhD-student
Dipl. Phys. Andreas Kreuzer, PhD-student
Dipl. Phys. Tobias Kluge, PhD-student
Martin Wieser, diploma student
Matthias Kopf, diploma student
Esther Beyersdorff, diploma student
Abstract
The research group ”Groundwater and Paleoclimate” employs a variety of environmental tracers, in
particular noble gases, in order to study physical processes in groundwater and other environmental
systems (e.g. lakes, ocean, and ice) as well as to reconstruct paleoclimate conditions recorded in old
groundwater and other archives (e.g. speleothems).
recharge
equilibration
excess air formation
3 H decay
climate information
2 H, 18 O
noble gases
222 Rn ingrowth
flow
equilibration
exchange
dispersion
mixing
14 C decay
He flux
time information
CFCs, SF 6 , 3 H
degassing
sampling
Figure 4.1: Schematic representation of the various tracers and processes studied in groundwater
Background
Climate change and the limited availability of water resources are interrelated issues of central scientific
and societal importance. Isotopic studies of groundwaters can address both issues by providing
information on i) past climatic conditions such as temperature or aridity and ii) physical parameters
such as residence time or recharge rate. Isotope and tracer techniques have played a central role in
the development of environmental physics, as methods from nuclear physics came to be applied to
problems of Earth and environmental science. Methods such as the use of stable isotopes in water as
climate proxies or the use of tritium and radiocarbon for dating of groundwater are now well established.
In addition to these methods, we employ dissolved noble gases in groundwater, which proved
to constitute a reliable paleotemperature proxy. Furthermore, He isotopes and other transient gas
tracers are important tools in groundwater dating. Yet, our interest is not limited to the application

4.1. GROUNDWATER AND PALEOCLIMATE 119
of these established methods, but includes the development of new analytical techniques to broaden
the range of tracers and archives in which they can be applied.
Main methods
The central facility of the group is a new mass spectrometric system for the analysis of noble gases
from water and gas samples. The system is used for measurements of all stable noble gases from
groundwater samples for studies of excess air and noble gas paleotemperatures. The system also
allows the analysis of He isotopes for 3 H- 3 He dating. Moreover, experimental procedures for the
extraction and analysis of noble gases from much smaller samples of fluid inclusions in speleothems
have been established successfully. This shows that the system is capable of handling samples with
noble gas contents varying over many orders of magnitude. The noble gas facility is complemented
by a radiometric 3 H lab. A mobile device for 222 Rn detection and a gas chromatographic system for
SF6 analyses are operated together with the limnophysics group. In addition we collaborate with the
stable isotope and 14 C laboratories of the institute for the respective analyses on water samples.
Projects and their links
Projects of the group are related either to questions of water resources or paleoclimate, or both.
Some projects are mainly applications of established methods, whereas others intend to develop new
methods and approaches. The DFG-funded project ”Groundwater China” is now in its final year. The
main goal to derive a noble gas paleotemperature record for East Asia has been achieved, although
the interpretation of the noble gas, stable isotope, and radiocarbon data remains complex (see report
of A. Kreuzer, section 4.1.1). Preliminary results of this study have been published in the framework
of the IAEA isotope hydrology series (Kreuzer et al., 2006).
The second aspect of the China project was to use the dating tools for young groundwater in order
to determine groundwater fluxes in the recharge area. An understanding of groundwater recharge is
of vital importance in the North China Plain, where piezometric levels have dramatically declined
in the past decades due to abstraction for irrigation. Our results show that 3 H- 3 He ages provide a
reasonable estimate of recharge rates, indicating ehanced recharge by irrigation return flow, whereas
the SF6 method is hampered by a not yet fully explained but apparently natural background (see
report of C. von Rohden, section 4.1.2). The determination of recharge and mixing rates is also
central to the project ”Groundwater Odenwald”, funded by the German State of Hessia, which also is
in its final phase. As in China, the 3 H- 3 He method works well and enables identification of zones of
young, old, and mixed groundwater, whereas the SF6 method is severly affected by natural sources.
Intriguing correlations of the SF6 background with the lithologies of the study area and with 4 He and
222 Rn contents of the groundwater have been found (see report of R. Friedrich, section 4.1.3).
In the framework of the new DFG research unit ”daphne” (see also section 6.1, Heidelberger Akademie
der Wissenschaften), a project has been started that investigates the possibility to derive paleotemperature
information from noble gases dissolved in microscopic water inclusions in speleothems. The
first achievements of this project are the establishment of precise methods for the determination of the
extracted water amounts and the analysis of the extracted noble gases. Results from the test samples
analysed so far have clearly shown that a reduction of the air-derived noble gas component will be
crucial for the success of the method (see report of T. Kluge, section 4.1.4).
Several current projects deal with issues related to gas partitioning between groundwater and entrapped
gas, including the observed phenomena of excess air and degassing. A comparatively comprehensive
theoretical description of these phenomena and their effects on the dissolved noble gases
in groundwater has recently been developed (see report of W. Aeschbach-Hertig, section 4.1.5).
A more detailed and quantitative understanding of the formation of excess air in groundwater is a
major goal of the EU-funded project ”‘ADNOGAPALIN”’, conducted by the Marie Curie fellow L.
Palcsu. Major steps towards a quantitative analysis of the factors that influence excess air amount
and composition have been taken by a recent field experiment and by the initiation of laboratory
experiments using sand columns (see report of L. Palcsu, section 4.1.6).
The field experiment on excess air formation took place at an artifical recharge site near Basel, where
parts of an alluvial plain are periodically flooded by Rhine water to replenish the groundwater. The
combined application of several tracers (noble gases, stable isotopes, radon) and monitoring of physical
parameters (water level, temperature, conductivity) enabled us to trace the infiltration of the surface
water and its mixing with the regional groundwater, as well as the rapid increase of the excess air
component during this process (see report of M. Kopf, section 4.1.7).
High levels of excess air or other dissolved gases can lead to degassing of groundwater during sampling.
The traditional way of sampling with copper tubes may be inadequate in such cases. We have adapted
and tested an alternative sampling technique with passive diffusion samplers, i.e. small gas volumes

120 CHAPTER 4. AQUATIC SYSTEMS
in a silicon tube that are equilibrated with groundwater in situ before being sealed and analysed. It
could be shown that results obtained by this method agree with copper tube samples under normal
conditions. A variety of aspects of the method, such as the equilibration time for different noble gases
and silicon tubes, have been investigated (see report of M. Wieser, section 4.1.8).
External Collaborations
Institute of Hydrogeology and Environmental Geology, Chinese academy of geological sciences, Zhengding,
China, Prof. Z. Chen (IHEG).
Physical Research Laboratory, Ahmedabad, India, Dr. S.K. Gupta (PRL).
Oxford Centre for Water Research, Oxford University, United Kindom, Prof. M. Edmunds (OCWR).
Hessisches Landesamt für Umwelt und Geologie, Wiesbaden, Germany, Dr. B. Leßmann (HLUG).
Institute of Isotope geochemistry and mineral resources, ETH Zürich, Switzerland, Prof. R. Wieler,
Dr. R. Kipfer (IGMR).
AMS Radiocarbon Dating Lab, ETH Zürich, Switzerland, Dr. I. Hajdas (AMS).
Climate and Environmental Physics, University of Bern, Switzerland, Dr. Roland Purtschert (KUP).
Applied and Environmental Geology, University of Basel, Switzerland, Dr. E. Zechner, Prof. P.
Huggenberger (UBA)
UFZ Leipzig-Halle, Isotope Hydrology, Dr. Stefan Weise, Dr. Karsten Osenbrück (UFZ).
Matter Wave Optics, Kirchhoff Institute for Physics, Prof. Markus Oberthaler (KIP).
Funding
The China project and the speleothem project are funded by the DFG, the Odenwald project is
funded by a contract with the Hessian authorities. Laszlo Palcsu is funded by the EU (Marie Curie
fellowship).
Publications
Peer reviewed
1. Aeschbach-Hertig et al. [2007]
2. Edmunds et al. [2006]
3. Aeschbach-Hertig [2006e]
Other publications
1. Kreuzer et al. [2006]
Diploma theses
1. Wieser [2006]
Invited talks
1. Aeschbach-Hertig [2006a]
2. Aeschbach-Hertig [2006d]
3. Aeschbach-Hertig [2006c]
4. Aeschbach-Hertig [2006f]
5. Aeschbach-Hertig [2006b]

4.1. GROUNDWATER AND PALEOCLIMATE 121
4.1.1 A tracer study of paleoclimate and groundwater recharge in the
North China Plain
Andreas M. Kreuzer (participating scientists: Christoph von Rohden, Werner Aeschbach-Hertig,
Chen Zongyu (IHEG), Rolf Kipfer (IGMR), Irka Hajdas (AMS))
Abstract Noble gas temperatures (NGTs), stable isotope ratios and 14 C-ages from old groundwater
in the North China Plain (NCP) are used to reconstruct a paleoclimate record. This is the first NGT
record from East Asia. Preliminary results indicate a glacial cooling of about 5 ◦ C .
19
18
17
16
15
14
13
12
11
10
9
8
7
53
32
33
31
44 52
43
39
48 49
50
40
45
10
41
46
36
10 20 30 40 50 10000 20000 30000 40000
47
15
11
12
19 14
37
38
9
20
18
17
Age (yrs)
Figure 4.2: The figure shows the noble gas temperatures for the samples from 2004 and 2005. The
warm temperatures of about 14 ◦ C in the modern samples correspond to the local annual air temperatures,
while there are still some outliers. The coldest late pleistocene samples have a temperature of
about 9 ◦ C which would indicate a 5 K cooling for the NCP during last glacial. Dating was done with
3 H- 3 He for modern samples and with 14 C for paleosamples.
Background Noble Gas concentrations in water
vary with temperature as the solubilities are
temperature dependent. Measurements of noble
gases in paleo-groundwater can therefore be used
to calculate paleo recharge temperatures. The importance
of this method lies in reliable determination
of glacial-interglacial temperature differences.
The age of the groundwater in the NCP reaches
from very young water to 35 kyr old water in the
deeper parts of the aquifers.
The goal of this study is to complement isotope
data from this aquifer system with NGTs in order
to quantify the climatic signal of the transition
from the last glacial maximum (LGM) to the
holocene.
Methods and results Data from two sampling
campaigns reflect a clear temperature signal between
the modern- and the paleosamples as shown
in the figure. In the modern group, a few outliers
are thought to be due to local effects of groundwa-
ter recharge, while the outliers in the paleogroup
are mainly referred to mixing processes and different
groundwater flow regimes.
The observed difference in temperature is used to
calibrate the δ 18 O-thermometer. The new value
for the long-term slope between temperature and
δ 18 O from modern to paleogroundwater is calculated
to be 0.6 ±0.15�/ ◦ C .
Outlook/Future work The main interpretation
is finished by the end of this year and will be
published in a PhD-thesis. It is planned to present
the results at international conferences and publications
are in preparation.
Funding This work is financially supported by
the DFG (DFG grant AE 93/1) and by the
National Natural Science Foundation of China
(NSFC grant No. 40472125)
Main publication Kreuzer et al. [2006]

122 CHAPTER 4. AQUATIC SYSTEMS
4.1.2 Dating young groundwater in the North China Plain
Christoph von Rohden (participating scientists: Andreas Kreuzer, Werner Aeschbach-Hertig, Chen
Zongyu (IHEG), Rolf Kipfer (IGMR))
Abstract A large aquifer system in the alluvial North China Plain was sampled for groundwater
along a transect. One of the sampling campaigns was intended to extract information about the
recharge and the residence times of young groundwaters. The SF6– and 3 H- 3 He dating techniques
were used, and the applicability of SF6 as dating tool was investigated.
SF 6 -conc [fmol/l]
3 H-conc. [TU]
3.0
2.5 (12°C)
2.0
1.5
1.0
0.5
25
20
15
10
5
0
0 10 20 30 40 50 60 70 80 90 100 110
distance [km]
20
15
10
5
SF 6 -age [yr]
equality
0
0 5 10 15 20 25 30 35
3 3
H- He-age [yr]
Figure 4.3: Left panel: SF6-concentrations along sampling transect. The dashed grey line indicates
the equilibrium concentration with recent atmosphere at 12 ◦ C (top). Bottom: 3 H-concentrations. A
clear transition from young post-bomb to older waters can be identified. Red symbols denote samples,
which should not contain SF6 due to the lack of 3 H (≥50 y). The large scatter and the level
SF6-concentrations, particularly in 3 H-free samples, imply natural (terrigenic) sources of SF6. Right
panel: Comparison of calculated apparent 3 H- 3 He– and SF6-ages. SF6-ages are clearly underestimated,
strongly limiting the use of SF6 as dating method.
Background Groundwater is the dominant water
source for municipal, urban and agricultural
use in the densely populated region (≈200 Mio
people) of the North China Plain (NCP). Concerning
a sustainable management, the growing
water demand in this semiarid region becomes
more and more problematic. Quantitative age information
of young groundwater in the recharge
area is crucial in this context.
Methods and results Besides the well established
3 H- 3 He-method, that in general gives reliable
results, we tested the use of SF6 as dating
tool. Both methods draw on the variable atmospheric
input to the hydrosphere within the last
≈40 years. The sampling took place from the Taihang
mountains in the west near Shijiazhuang to
the centre of the NCP.
The results suggest that the unconfined (upper)
aquifer is — at least in parts — recently
recharged. However, the model ages calculated
from the SF6-measurements are to a large extent
not consistent with the 3 H- 3 He ages. Many SF6samples
have a distinct excess, most prominently
in samples without tritium. Natural sources of
SF6 must be discussed as explanation, which is
uncommon for fluvial or alluvial deposits. The
applicability of SF6 as — at least exclusive — dating
tool for young groundwater in this region must
therefore be put into question.
Based on the reliable 3 H- 3 He data we interpret the
distribution of the apparent tracer ages against
the background of extensive irrigation to be a result
of the recharge possibly influenced by strong
groundwater use (depression cones) in the urban
area of Shijiazhuang.
Funding The work was supported by the German
Research Foundation (DFG).
Main publication The study was presented at
the IAH conference in Beijing (von Rohden et al.
[2006]) and is in preparation for publication.

4.1. GROUNDWATER AND PALEOCLIMATE 123
4.1.3 A multi tracer study to investigate the groundwater in the Odenwald
region
Ronny Friedrich (participating scientists: Werner Aeschbach-Hertig, Bernhard Leßmann (HLUG),
Guido Vero (HLUG), Rolf Kipfer (IGMR))
Abstract Three sampling campaigns where performed during 2003, 2004 and 2005 in the Odenwald
region (Germany). This multi tracer study (noble gases, 3 H, δ 18 O, δ 2 H, SF6, 222 Rn) investigates the
age structure, mixing ratios and recharge areas of the groundwater in this region.
S F 6 a g e [y r b . 2 0 0 5 ]
4 0
3 5
3 0
2 5
2 0
1 5
1 0
5
0
0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0
3 H / 3 H e a g e [y r b . 2 0 0 5 ]
c ry s t.
re e d
s a n d s t.
H S d e p r.
Figure 4.4: Comparison of ages obtained by SF6 and 3 H- 3 He of samples from 2005. Different symbols
reflect geological origin (⊙ = crystalline rocktype, ⋄ = Hessian reed, ∆ = sandstone rocktype, ∇ =
Hanau-Seeligenstaedter depression). Arrows indicate ages older than 40 years. Samples above the
1:1 line indicate mixing between old (tracer free) and young (tracer bearing) groundwater. Samples
below 1:1 line could be influenced by natural SF6. Especially samples from the crystalline part are
influenced.
Background The mountainous Odenwald region
in the federal state of Hessia (Germany) is
one of the main local recharge areas for groundwater
of the surrounding depressions, where substantial
extraction for public water supply takes
place. Therefore we investigate the groundwater
in the Odenwald to study residence times and mixing
ratios, define regions of groundwater recharge
and understand the groundwater inflow from the
Odenwald to the surrounding areas.
Methods and results This study includes different
stable and radioactive gas and isotope tracers
such as 2 H, 18 O, 3 H, noble gases, 222 Rn and
SF6 . Based on the stable isotope data it is possible
to distinguish between groundwater from different
areas of the Odenwald. This will help us to
define source regions for the groundwater in the
surrounding areas. Additionally the isotopic signatures
show that the groundwater was formed
by ”annual” precipitation and not only in winteror
summertime. Noble gases (He, Ne, Ar, Kr,
Xe) can be used in principle to calculate recharge
temperatures or the infiltration altitudes (above
sea level) of recharge areas. Furthermore noble
gases give important information to correct other
gas tracers for so called ”excess air” that oversaturates
gases in groundwater (see Kipfer et al.
[2002] for a review of the methods). Comparing
the results of the two independent dating methods
- SF6 and 3 H- 3 He - we found that dating with
SF6 is not possible in the crystalline region of the
Odenwald. The results indicate that SF6 is influenced
by a natural source in the subsurface that
varies with lithology (see Busenberg & Plummer
[2000]). 222 Rn and radiogenic 4 He data from part
of the wells seem to be related to the natural SF6,
consistent with the idea of radiochemical SF6 production
in rocks supported by radiochemical reactions.
Data from the 3 H- 3 He method give robust
groundwater ages in the range of some years to
values higher than 40 years. Furthermore, regions
where mixing of old and young groundwater occurred
can be distinguished.
Outlook/Future work Data analysis is still in
progress. Comparing tracer results with hydrogeological
and hydrochemical data should lead to a
better system description.
Funding This work is done in cooperation with
the ”Hessisches Landesamt für Umwelt und Geologie”
Wiesbaden.
Main publication Friedrich et al. [2006]

124 CHAPTER 4. AQUATIC SYSTEMS
4.1.4 Noble gas measurements on fluid inclusions in speleothems
Tobias Kluge (participating scientists: Werner Aeschbach-Hertig)
Abstract Dissolved atmospheric noble gases in groundwater constitute a reliable paleothermometer,
based on their precisely known temperature-dependent solubilities. This archive is limited due to the
dispersive mixing and dating problems. In contrast, speleothems can be well dated using uraniumthorium
dating. However there is no paleothermometer comparable to the noble gas thermometer so
far. The idea of this project is to combine the advantages of both archives.
Xe (ccSTP/g)
1.2x10 -7
8.0x10 -8
4.0x10 -8
aew
0.0 1.0x10 -5
0.0
2.0x10 -5
Ne (ccSTP/g)
Kr (ccSTP/g)
3.0x10 -5
1.6x10 -6
1.2x10 -6
8.0x10 -7
4.0x10 -7
aew
0.0 4.0x10 -3
0.0
8.0x10 -3
Ar (ccsTP/g)
Figure 4.5: Noble gas concentrations for the elements Ne, Ar, Kr and Xe, calculated for stalagmite
samples in a first measurement series. The points in the blue circle are values of air-equilibrated water
at temperatures between 0 o C and 30 o C. The black lines indicate addition of ”excess-air” (upper
line: water at 0 o C, lower line: water at 30 o C). Most of the samples show ratios in the expected
area, i.e. they are situated on the mixing line of equilibrated water with unfractionated air. However
the uncertainties are quite large and typically in the range of 10%. Only the best sample has an
uncertainty of 2-3%.
Background Noble gases in groundwaters can
be used to reconstruct paleotemperature due to
the temperature-dependent solubility. Additionally,
the noble gas concentrations in groundwater
are affected by dissolution of trapped air bubbles.
The effect of this so-called excess-air can be corrected.
If noble gases are extracted from fluid inclusions
in stalagmites, similar patterns can be detected
(see figure). Compared to groundwater, stalagmite
samples have much less water (4 orders of
magnitude), but a 100 times higher excess-air to
water ratio. Therefore the calculation of noble gas
temperatures becomes difficult.
Methods and results Noble gases have been
exctraced from the stalagmites by crushing, respectively
heating the sample in evacuated copper
tubes. In the next step the amount of released water
was determined using the water vapour pressure.
The extracted water amount is strongly dependent
on the stalagmite (H12 (Oman) 0.25 wt%,
MA1 and MA2 (Chile) 0.01 wt%, OBI 5 (Austria)
0.004 wt%) and on the techniques (crushing,
heating, microwave treatment).
The noble gas measurements are performed by
1.2x10 -2
mass spectrometry . For the calculation of absolute
noble gas amounts a diluted air standard
is used. The reproducibility of standard measurement
is in the range of 1–2%. Sample uncertainties
have been much higher, because of a high
and variable background and additionaly in some
cases low noble gas signals. Nevertheless the background
corrected Xe-Ne and Ar-Kr plot are indicating
that the values are not far away from the
expected mixing between noble gases from water
filled inclusions and some unfractionated ”excessair”.
Calculation of noble gas temperatures in case of
the best samples (from a cave with a recent cave
temperature of 26 o C) leads to 26, respectively
30 o C (although with very large uncertainties) using
the inverse modelling technique of Aeschbach-
Hertig et al. [1999]. This may be a hint that
noble gases from fluid inclusions can be used to
determine noble gas temperatures if the problems
(high uncertainties, high water/air volume ratios)
can be managed.
Funding This work is financially supported by
the DFG (grant AE 93/3) as part of the DFG-
Forschergruppe DAPHNE.

4.1. GROUNDWATER AND PALEOCLIMATE 125
4.1.5 Gas partitioning in groundwater
Werner Aeschbach-Hertig
Abstract Using dissolved gas concentrations in groundwater to derive residence times and recharge
temperatures requires an adequate understanding of observed excesses and sometimes deficits of atmospheric
gases. A comprehensive theory has been developed that explains both excess air and degassing
with a single model equation describing equilibrium gas partitioning.
concentration relative to equilibrium
1
0.8
0.6
0.4
0.2
LPA17
LPA20
LPA22
LPA23
LPA23b
Ne Ar Kr Xe
Noble Gas
LPA32
LPA32b
LPA33
LPA38
LPA39
Figure 4.6: Measured (symbols) and modeled (lines) concentrations of the atmospheric noble gases
relative to solubility equilibrium in 10 degassed samples from the Ledo-Paniselian Aquifer in Belgium
(unpublished data). The generalised CE-model describes most samples reasonably well, even strongly
degassed ones.
Background The partitioning of gases between
groundwater and soil air is important for a variety
of issues, such as the availability of oxygen,
the fate of volatile contaminants, and the distribution
of gaseous tracers. Several widely used environmental
tracer methods are based on gases,
e.g. CFCs, SF6, He isotopes, or radon. The atmospheric
noble gases are usually used to derive
recharge temperatures, but are also powerful tools
to trace and study gas partitioning.
Methods and results Many noble gas studies
have clearly shown the widespread presence
of a gas excess above atmospheric solubility equilibrium
(so-called ”excess air”) in groundwater.
An increasing number of studies, however, also
reports undersaturations, which are attributed
to degassing. A quantitative understanding of
the patterns of dissolved noble gases in groundwater
is required for a reliable determination of
noble gas recharge temperatures and gas tracer
ages. Models assuming a diffusion-controlled degassing
process can often be ruled out because of
the absence of an indicative isotope fractionation.
Instead, both excesses and deficits of dissolved
gases in groundwater can be explained by equilibrium
partitioning of gases between the water
and trapped gas bubbles. The concept of closed-
system equilibration (CE-model) proved very successful
in modeling excess air [Aeschbach-Hertig
et al. , 2000]. It can also be used to model the
loss of dissolved gases that occurs if gas bubbles
form in the subsurface. Excess air appears to
be closely related to water table fluctuations and
related pressure variations in the recharge zone.
Degassing could be due to the accumulation of
geogenic or biogenic gases and/or a pressure decrease
in the groundwater discharge area. Currently
only few complete noble gas data sets of degassed
groundwaters exist, which could be used to
test the applicability of the generalised CE-model
to describe degassing. In the available cases, the
model performs reasonably well.
Outlook/Future work Simple laboratory experiments
are currently performed to verify the
model concept. Further field data sets are required
in order to test the model’s usefulness in
deriving recharge temperatures and tracer ages
from degassed samples
Main publication A paper describing the recent
advancements in model formulation is in
preparation, an invited conference presentation
has been given [Aeschbach-Hertig, 2006d].

126 CHAPTER 4. AQUATIC SYSTEMS
4.1.6 Laboratory and field experiments on the formation of excess air in
groundwater
Laszlo Palcsu (participating scientists: Werner Aeschbach-Hertig)
Abstract Excess air is a contribution to the gases dissolved in groundwater in addition to the
solubility equilibrium component, formed by partial or total dissolution of air trapped during water
level rises in the unsaturated zone. The amount of excess air can be quite large, mainly if the water
level increase is significant, for example in case of recharge from ephemeral streams in semi-arid
regions or artificial recharge. One of the main goals of this project is to investigate the mechanisms
that control the excess air formation.
Figure 4.7: a. Study site at Danube River b. Plexiglas columns for laboratory experiments
Background We examine the formation of excess
air under field and laboratory conditions using
all five noble gases. In laboratory experiments
with plexiglas columns filled with different types
of sand, we investigate how the excess air amount
and composition depend on the hydrostatic pressure
as well as the size distribution of the sand and
the entrapped air bubbles. In field experiments
we study the relationship between excess air and
water level fluctuations. Two study sites were selected
where the groundwater level increased due
to artificial recharge (Basel, Switzerland) and due
to river floods (Danube River, Hungary).
Methods and results In the mass spectrometric
measurements of noble gases dissolved in water
we could achieve a quite good reproducibility (0.6
% for helium, 0.6 % for neon, 0.3 % for argon,
0.8 % for krypton, and 1.0 % for xenon), however
we still have a few-percent systematic difference
between the obtained and the expected values.
Presently, test are conducted to identify the
source of these deviations.
Besides the technical improvements, preparation
and sampling have been done in the laboratory
column experiments as well as in the field work.
All-plastic columns have been built to perform
excess air experiments under well known conditions
(see Figure 1.b). We filled two columns with
sand particles, one with fine, the other with coarse
sand. In the first experiments we would like to
find correlations, among others, of the excess air
amount and fractionation with hydrostatic pres-
sure, entrapped air abundance and bubble size distribution.
A few sampling campaigns have been
already carried out, the samples will be measured
soon.
To examine the excess air formation under natural
conditions, we have chosen a field site along
the Danube River, Hungary. Five sampling tubes
have been built into the wall of a dug-well (see
Figure 1.a). During a flood in the Danube River,
the groundwater surface will be increasing, thus
entrapped soil gases can produce excess air in the
area of the dug-well. From the sampling tubes,
one can take water samples which represent always
a defined depth. After wintertime, the flood
in the Danube River can exceed 4-5 m, which
seems to be an excellent possibility to find in-situ
produced excess air in the groundwater depending
on the water level increase.
Outlook/Future work Having the measured
noble gas concentrations we can describe the
formed noble gas pattern using different dissolution
models such as the closed-system equilibration
model [Aeschbach-Hertig et al. , 2000]. In
the excess air pattern, the bubble size distribution
might play a role, therefore we intend to investigate
the entrapped air amount and distribution
within the sand in the column experiments using
X-ray tomography.
Funding This project is supported by the Marie
Curie Intra-European Fellowships program (reference
number: 009562).

4.1. GROUNDWATER AND PALEOCLIMATE 127
4.1.7 Excess air formation at an artificial recharge site
Matthias Kopf (participating scientists: Laszlo Palscu, Werner Aeschbach-Hertig, Eric Zechner
(UBA))
Abstract Correlations between excess air and environmental conditions during groundwater recharge
are examined. A field experiment at an artificial recharge site as well as laboratory column experiments
are conducted in order to determine in detail how different parameters influence the formation
of excess air.
���
��
��
��
��
��
�
�������������������
������������������
�
� �� �� �� �� ��� ���
���������������� ��������� �
Figure 4.8: Ne excess ∆Ne versus distance from the infiltration area in the test field Stellimatten
near Basel. A significant increase of ∆Ne takes place between surface water and the freshly infiltrated
water in the infiltration area followed by mixing with background groundwater.
Background Surface water infiltrating the
ground is equilibrated with the atmosphere, its
dissolved noble gas concentrations reflecting the
soil temperature because of the temperature dependence
of the Henry coefficients. However, as
the groundwater level increases as a result of the
infiltration, bubbles of air are entrapped in the
groundwater, adding an excess component to the
dissolved gases (the so-called excess air). In order
to determine paleo recharge temperatures from
the equilibrium component, the accumulation of
excess air has to be understood. Column tests
with sand of different granulation and field experiments
in areas with well-known recharge conditions
are performed to study the correlation of
excess air with parameters such as pressure variation
during groundwater level changes.
Methods and results A field experiment has
been conducted at an artificial recharge site (Stellimatten)
operated by the water works of the city
of Basel. The sequence of alluvial deposits at
this site ranges from silty clay to coarse-grained
gravel with hydraulic conductivity values between
9 · 10 −7 m/s and 2 · 10 −3 m/s. The study area lies
in a steady groundwater stream, to which periodically
every 30 days Rhine water is added by
flood irrigation. This infiltration lasts 10 days,
afterwards the flooded area is allowed to regenerate
for 20 days. During such a cycle, samples for
radon, dissolved noble gases, stable isotopes and
SF6 were taken. Groundwater level changes, temperature,
and conductivity were monitored.
Very well visible is the accumulation of radon in
the infiltrated Rhine water and the mixing with
the existing groundwater. At the surface, the
infiltrating Rhine water has an activity of < 6
Bq/l, increasing to < 20 Bq/l as it reaches the
aquifer. At the end of the test field the water
has an activity of < 70 Bq/l, comparable to the
steady groundwater stream (A ≈ 80 Bq/l), indicating
mixing with the groundwater. The stable
isotopes show a clear separation of the groundwater
stream ( δ 2 H≈-68�) from the Rhine water
( δ 2 H ≈-77�), mixing with increasing distance
from the infiltration point. In addition, an accumulation
of the relative Ne excess ∆Ne (a measure
of excess air) along the flow path is noticed, starting
at nearly zero ∆Ne in the infiltrating Rhine
water. Immediately after infiltration the ∆Ne increases,
indicating formation of excess air. In the
flow path, mixing between groundwater and infiltrated
Rhine water takes place, seen in the dispersion
of ∆Ne (see figure). The groundwater level
changes show a correlation with ∆Ne and therefore
excess air.
Outlook/Future work In the data obtained
from Stellimatten we look for further correlations
of excess air with parameters naturally influencing
its formation (e.g. geology, biology). The lab
experiments will allow us to explore such correlations
under even better controlled conditions.
If robust correlations are found, dissolved noble
gases in groundwater may not only be used to
derive paleotemperatures but also as a proxy for
other recharge conditions (e.g. water level fluctuations)

128 CHAPTER 4. AQUATIC SYSTEMS
4.1.8 Collecting dissolved gases in water by diffusion samplers
Martin Wieser (participating scientists: Werner Aeschbach-Hertig)
Abstract A new sampling method to extract dissolved noble gases from groundwater by in-situ
equilibration with a small gas volume separated by a semi-permeable membrane (so-called diffusion
sampler) has been established. Lab and field experiments were conducted to test the functionality
and efficiency of the method.
Figure 4.9: Adaptation curve of nitrogen saturated diffusion samplers in air saturated water. Shown
is the curve for 40 Ar. Embedded is a schematic drawing of a diffusion sampler
Background The dissolved noble gas content in
groundwater is a significant palaeoclimatic tool for
determination of the infiltration temperature. In
order to measure the concentration of these noble
gases, sampling of the water for later analysis is an
important issue. Besides the original method to
take water samples in copper tubes, a new method
of diffusion samplers has been proposed [Sanford
et al. , 1996].
Methods and results The conventional sampling
method is to store a certain amount of water
in copper tubes whose ends are clenched off
by steel clamps. This water can be extracted on a
high-vacuum line to receive the dissolved gases for
mass spectrometrical analysis. In the new method
of passive diffusion samplers gas containers with
a diffusive membrane are used, which are introduced
into the water and stay there for about two
days. During this time the dissolved gas content of
the water equilibrates with the gas volume in the
container. This container is built by two copper
tubes whose open sides are connected via a silicone
tube, which represents the membrane (see
fig. 4.9). After removing the sampler, the copper
tube containing the sampled gas is clenched
off by a hydraulic plier to make a gas-tight sample.
The measurement of this gas sample in conjunction
with the determination of the total dissolved
gas pressure (TDGP) provides the same information
as the analysis of water samples. A new
multiprobe that inclueds a TDGP probe has been
tested and applied.
The determination of the sampler’s equilibration
time was a major topic of the research. This time
depends on the permeability of the membrane and
therefore on the noble gas. By preparing diffusion
samplers in a nitrogen atmosphere and equilibrating
them in air saturated water for defined times,
I could estimate the adaptation times of the exponential
saturation curve for several wall thicknesses
of the silicone tube. Other experiments
with degassed or oversaturated water were carried
out similarly. The noble gas with the longest
adaptation time, according to their permeability
in silicone rubber, was neon, xenon was the
fastest.
The samplers as well as the multiprobe were used
for several field experiments including a groundwater
well near Willersinnweiher in Ludwigshafen
and a mining lake in Brandenburg. Also, comparisons
with the conventional method both in the
lab and the field have been carried out.
Results show the usefulness of the new method as
an addition to the conventional method.
Outlook/Future work After having installed
the infrastructure for measurements of gas samples
and establishing the use diffusion samplers,
the method can be incorporated in field campaigns
to come. Furthermore, a study of the total gas
composition could be conducted.

4.1. GROUNDWATER AND PALEOCLIMATE 129
References
Aeschbach-Hertig, W. 2006a. Edelgase im Grundwasser als Tracer und Klimaindikatoren. Invited
talk, Kolloquium Erdwissenschaften, University of Basel, Switzerland.
Aeschbach-Hertig, W. 2006b. Edelgase und ”Excess Air” im Grundwasser. Invited talk, Hydrologisches
Kolloquium, University of Freiburg, Germany.
Aeschbach-Hertig, W. 2006c. Environmental tracers in groundwater studies - Case study North China
Plain. Invited talk, School of Environmental Science and Engineering, Chang’an University, Xi’an,
China.
Aeschbach-Hertig, W. 2006d. Groundwater age dating with gas tracers: The role of gas partitioning.
Invited key presentation, Annual Meeting of the Geological Society of America (GSA), Philadelphia,
USA.
Aeschbach-Hertig, W. 2006e. Rebuttal of ”On global forces of nature driving the Earth’s climate. Are
humans involved?”. Env. Geol. DOI 10.1007/s00254-006-0519-3.
Aeschbach-Hertig, W. 2006f. Spurenstoffmethoden zur Erforschung des Grundwassers. Invited talk,
Rhein-Neckar Gesprächskreis, Heidelberg, Germany.
Aeschbach-Hertig, W., Peeters, F., Beyerle, U., Beyerle, U., & R., Kipfer. 1999. Interpretation of
dissolved atmospheric noble gases in natural waters. Water Resour. Res., 35, 2779–2792.
Aeschbach-Hertig, W., Peeters, F., Beyerle, U., & R., Kipfer. 2000. Palaeotemperature reconstruction
from noble gases in ground water taking into account equilibration with entrapped air. Nature,
405, 1040–1044.
Aeschbach-Hertig, W., Holzner, C. P., Hofer, M., Simona, M., Barbieri, A., & Kipfer, R. 2007. A
time series of environmental tracer data from deep meromictic Lake Lugano, Switzerland. Limnol.
Oceanogr., 52, 257 – 273.
Busenberg, E., & Plummer, N. L. 2000. Dating young groundwater with sulfur hexafluoride: Natural
and anthropogenic sources of sulfur hexafluoride. Water Resour. Res., 36, 3011–3030.
Edmunds, W. M., Ma, J.Z., Aeschbach-Hertig, W., Kipfer, R., & Darbyshire, D.P.F. 2006. Groundwater
recharge history and hydrogeochemical evolution in the Minqin Basin, North West China.
Appl. Geochem., 21, 2148–2170.
Friedrich, R., Aeschbach-Hertig, W., Vero, G., & Leßmann, B. 2006. A multi tracer study to investigate
the groundwater in the Odenwald region, Germany. In: Annual Meeting of the Geological Society
of America (GSA), abstracts. Philadelphila: Geological Society of America (GSA).
Kipfer, R., Aeschbach-Hertig, W., Peeters, F., & Stute, M. 2002. Noble gases in lakes and ground waters.
Pages 615–700 of: Porcelli, D., Ballentine, C., & Wieler, R. (eds), Noble gases in geochemistry
and cosmochemistry. Rev. Mineral. Geochem., vol. 47. Washington, DC: Mineralogical Society of
America, Geochemical Society.
Kreuzer, A. M., Zongyu, C., Kipfer, R., & Aeschbach-Hertig, W. 2006. Environmental Tracers in
Groundwater of the North China Plain. Pages 136–139 of: IAEA (ed), Isotopes in Environmental
Studies - Aquatic Forum 2004. Vienna: IAEA.
Sanford, W. E., Shropshire, R. G., & Solomon, D. K. 1996. Dissolved gas tracers in groundwater:
Simplified injection, sampling, and analysis. Water Resour. Res., 32, 1635–1642.
von Rohden, C. L., Kreuzer, A. M., & Aeschbach-Hertig, W. 2006. Dating Young Groundwater in
the North China Plain. In: Groundwater – Present Status and Future Task, Abstracts. Beijing:
International Association of Hydrogeologists.
Wieser, M. 2006. Entwicklung und Anwendung von Diffusionssamplern zur Beprobung gelöster Edelgase
in Wasser. diploma thesis, Universität Heidelberg.

4.2. LAKE RESEARCH (LIMNOPHYSICS) 131
4.2 Lake Research (Limnophysics)
Johann Ilmberger
Group members
Dr. Johann Ilmberger, head of group
Dr. Christoph von Rohden, postdoc
Christian Ebert, Diploma student
Daniel Osusko, Staatsexamen student
Abstract
Water quality of lake waters is, among other factors, affected by mixing and transport processes in
the interior, as well as by the exchange with the ambient ground water. These internal processes and
the ground water exchange are the main subjects of our investigations.
rain
groundwater
“old”
groundwater
heat exchange
Sep Jan
el. conductivity
erosion
wind
circulation
& convection
eddydiffusion
anaerobic
evaporation
temperature
Jan
~8 m
Sep
epilimnion
thermocline
hypolimnion
?
chemocline
?
?
monimolimnion
Figure 4.10: Schematic diagramm of transport processes in lakes.
Background
Transport processes in lakes are important for the lake water quality. Especially mining lakes tend to
have a poor quality because of the disturbed landscape due to the mining activities.
Methods and results
The investigations are based on tracers and direct measurements. Mainly we are using the tracer SF6,
but also stable isotopes and now upcoming Radon. Recently we started another Diploma work to
improve the Radon measurements.
The background level of SF6 can be used to study the interaction of groundwater with lake water.
This is based on the equilibration of rain and surface waters with atmospheric gases and the increase
of the atmospheric level of the man made SF6 during the last decades. Therefore groundwater — as
it normally infiltrated a few decades ago — has a low SF6 content, while the lake water SF6 concentration
is, at least during overturn, close to the higher atmospheric concentration. This difference of
the signals can be used to study groundwater – lake water exchange. We apply this method to the
gravel lake Willersinnweiher [Wollschläger et al. , 2006] and the mining lake Moritzteich (see section
4.2.2).
We use SF6 spike experiments to investigate vertical mixing and groundwater exchange. There we inject
a small amount SF6 (few hundred mg) into the deep water body and trace the vertical spread and
the balance by profile measurements. We applied this method to Lake Constance, Lake Hufeisensee,
Lake Merseburg-Ost 1a and 1b. This summer we started a spike experiment at Lake Waldsee using 0.3
mg SF6, which we injected right above the sediment. First measurements show a rather fast spread
of the tracer towards the lake surface.
Direct measurements include the profile measurements of temperature and electrical conductivity with
a CTD-probe at a vertical resolution of ∼2 cm. Direkt measurements we used to calculate the vertical

132 CHAPTER 4. AQUATIC SYSTEMS
transport in Willersinweiher [von Rohden et al. , 2006].
Lakes in investigation: Mining lake Merseburg-Ost 1a, Mining lake Merseburg-Ost 1b, Lake Willersinnweiher,
Lake Waldsee, Lake Moritzteich.
The tracer methods, especially the spike experiments, are very well suited for the transport investigations.
Projects and funding
The SF6 spike measurements at the mining lakes Merseburg-Ost 1a and 1b were funded by the Centre
of Environmental Research Leipzig-Halle and performed in close collaboration with B. Boehrer (UFZ-
Leipzig/Halle, Section Gewässerforschung, Magdeburg).
In the future we will intensify the research using radon as limnic tracer, as the work of Tobias Kluge
[Kluge et al. , n.d.] has shown its potential as tracer for the groundwater exchange of gravel lakes.
In a joined project, funded by the German Research Foundation, we investigate vertical transport and
groundwater exchange at two mining lakes (Lake Waldsee and Lake Moritzteich).
Collaborations
Helmholtz-Zentrum fr Umweltforschung GmbH – UFZ, Dept. of Lake Research Magdeburg and Dept.
of Isotope Hydrology Halle
BTU Cottbus, Lehrstuhl Gewässerschutz
Institute for Biodiversity and Ecosystem Dynamics/Aquatic Microbiology, University of Amsterdam
Limnologisches Institut, Universität Konstanz
Institut für Seenforschung, Langenargen, LfU
Peer Reviewed Publications
1. Wollschläger et al. [2006]
2. von Rohden et al. [2006]

4.2. LAKE RESEARCH (LIMNOPHYSICS) 133
4.2.1 Empirical mode decomposition: A tool to analyse time series
Johann Ilmberger (participating scientists: Christoph von Rohden)
Abstract
Empirical mode decomposition (EMD), which is a new method to analyse non linear and non stationary
data, is applied to measured time series of water currents.
Background
Data analysis is an essential part in research and
much effort has to be taken to extract information
from measurements about ongoing processes.
Usual data analysis assumes linear and stationary
processes. At a first order approach, many systems
can be treated linear. Restricting the analysis
to appropriate time scales, also the stationary
assumption holds and one might get acceptable
results.
Methods and results
A useful tool to analyse non stationary and non
linear data is the ”empirical mode decomposition”
(EMD), which was introduced by N.E. Huang
(Huang [2005]; Huang et al. [1996, 1998]). The
method is based on the identification of the intrinsic
oscillatory modes by their characteristic time
scales in the data empirically, and decomposing
the data accordingly. The advantage of the EMD
is, that data of non stationary and non linear systems
can be analysed. The decomposition is based
on the assumption that any time series consists
of different simple intrinsic modes of oscillations.
Each intrinsic mode function (IMF), linear or non-
linear, has the same number of extrema and zerocrossings.
In 2004 we performed current measurements in a
small stratified lake in the Rhine valley using a
acoustic current profiler (ADCP). The currents in
the lake are very low and the signal is rather noisy.
Figure 11 shows a record of the north component
of the current velocity at a water depth of 4.4 m.
The signal is a 5 min mean, very noisy and does
not show much of a structure. To analyse this
signal, the empirical mode decomposition was applied.
The whole set of the resulting IMF’s and
the residue is shown in figure 12. The first IMF,
or may be the first and second IMF, can be addressed
to the signal’s noise, while the third and
fourth clearly show a structure in the data, which
is quite intermittent and wave package like.
Funding
This work was funded by the German Research
Foundation (DFG).
Main publication
Contribution to the Workshop on Physical Processes
in Natural Waters, Granada, 2006.

134 CHAPTER 4. AQUATIC SYSTEMS
4.2.2 Hydrology and vertical transport of meromictic mining lakes traced
with SF6 on the background level
Christoph von Rohden (participating scientists: Johann Ilmberger)
Abstract According to the solubility and the atmospheric input function, the anthropogenic gas
SF6 causes characteristic signals in surface waters and groundwater. We use this signal to trace
quantitatively hydrological processes in meromictic mining lakes. From depth and time dependent
SF6-contents in the water column and in connected groundwaters we estimate vertical transport and
— using the time information of the SF6-input — the coupling to the groundwater.
Depth [m]
0
2
4
6
8
10
12
14
16
Temperature
6 8 10 12 14 16 18
Thermocline
(Metalimnion)
Monimolimnion
Epilimnion
Chemocline
18
1000 1200 1400 1600 1800 2000
El. conductivity κ 25 [μS/cm]
0.0 0.5 1.0 1.5 2.0 2.5 3.0
SF 6 - conc. [fmol/l]
Figure 4.11: Left: El. conductivity (25 ◦ C) and temperature at 6.9.2006 in Moritzteich (Lusatia, East
Germany). The water column can be divided into the partly mixed epilimnion, the temperature stratified
thermocline region (no distinct hypolimnion), followed by the chemocline (chemically stratified),
and the anaerobic and partly chemically stratified monimolimnion. The monimolimnion is stable
against vertical mixing. Right: SF6-concentrations at 6.9.2006 (exemplary). Lake surface is in equilibrium
with atmosphere, deeper layers have higher SF6 remained from the last mixing (∼7 m depth).
Very low concentrations in the monimolimnion indicate a comparatively high water age (≥40 y).
Background Man made lakes, that form after
cessation of open pit mining, are often problematic
concerning the hydro-geochemical and biological
development. Especially in meromictic
lakes, that do not mix to the bottom, anaerobic
monimolimnia can act as contaminant source.
Knowledge about vertical mixing pattern, that are
driven by wind and influenced by density stratification,
morphology and the connection to the
groundwater is therefore crucial for possible remediation
and renaturation strategies. The stratification
particularly at the interface between aerobic
and anaerobic waters (chemocline) can be selfpreserving
due to hydrochemical conversions and
is therefore of interest.
Methods and results Water samples with up
to 20 cm depth resolution are taken monthly and
measured for SF6. High resolution CTD-profiles
document the density statification. Vertical transport
and groundwater exchange times will be derived
from tracer balances (SF6, heat) using budget
methods. Hydrochemical analysis and stable
isotope measurements of our project partners extend
the data base for interpretation. SF6 data
(see figure) reveal that the chemocline acts as efficient
barrier for vertical exchange. Very low concentrations
in the monimolimnion indicate an exchange
with old groundwater (≥40 y) or the detachment
from the atmosphere for a similar time
scale.
Funding The work is supported by the German
Research Foundation (DFG).
Main publication First results are in preparation
for publication.

4.2. LAKE RESEARCH (LIMNOPHYSICS) 135
References
Huang, N. E. 2005. Introduction to Hilbert-Huang Transform and its Associated Mathematical Problems.
In: Hilbert-Huang Transform in Engineering, vol. 1-32. New York: CRC Press.
Huang, N. E., Long, S. R., & Shen, Z. 1996. The Mechanism for Frequency Downshift in Nonlinear
Wave Evolution. Adv. Appl. Mech., 32, 59–111.
Huang, N. E., Shen, Z., Long, S. R., Wu, M. C., Shih, H. H., Zheng, Q., Yen, N.-C., Tung, C. C., &
Liu, H. H. 1998. The empirical mode decomposition and the Hilbert spectrum for nonlinear and
non-stationary time series analysis. Proc. R. Soc. London, Ser. A, 454, 903–995.
Kluge, T., Ilmberger, J., von Rohden, C., & Aeschbach-Hertig, W. A method for Radon-222 Measurement
in Lakes to study Groundwater Inflow. Submitted to L&O methods.
von Rohden, C., Wunderle, K., & Ilmberger, J. 2006. Parametrization of the vertical transport in a
small thermally stratified lake. aquatic sciences accepted.
Wollschläger, U., Ilmberger, J., Isenbeck-Schrter, M., Kreuzer, A., von Rohden, C., Roth, K., &
Schäfer, W. 2006. Coupling of groundwater and surface water at Lake Willersinnweiher: Groundwater
modelling and tracer studies. aquatic sciences accepted.

Small-Scale Air-Sea Interaction
5.1 Small-Scale Air-Sea Interaction . . . . . . . . . . . . . . . . . . . . . . . . 139
137

5.1. SMALL-SCALE AIR-SEA INTERACTION 139
5.1 Small-Scale Air-Sea Interaction
Group members
Prof. Dr. Bernd Jähne, head of group
Dr. Günther Balschbach, staff
Dr. Kai Degreif, Postdoc
Dr. Christoph Garbe, Postdoc
Dr. Uwe Schimpf, Postdoc
Dipl.Phys. Aleaxandra Herzog, PhD student
Dipl.Phys. Kerstin Richter, PhD student
Dipl.Phys. Markus Jehle, PhD student
Dipl.Phys. Roland Rocholz, PhD student
Dipl.Phys. Markus Schmidt, PhD student
Dipl.Chem. Achim Falkenroth, PhD student
Abstract
Research in small-scale air-sea interaction at the IUP concentrates on air-sea gas exchange and the
dynamics of wind-waves. The basic mechanisms are studied in laboratory experiments in a unique annular
wind-wave facility (The Heidelberg Aeolotron), other laboratory facilities, and field experiments
using imaging techniques for quantitative visualization of the water surface structure (wind waves),
the flow field, concentration fields by laser-induced fluorescence, and the water surface temperature
by passive and active thermography.
Scientific Objectives
The basic scientific objective is a better physical understanding of air-sea gas transfer, the dynamics
of short wind waves, and the micro turbulence at the ocean surface.
Currently the following topics are investigated:
1. The influence of the diffusion coefficient (or the Schmidt number Sc) on the transfer velocity
of gases. Together with the transfer velocity itself, this is a sensitive measure to distinguish
different models.
2. The influence of wind waves on air-sea gas transfer by enhancing the turbulence near the water
surface.
3. The influence of chemical reactivity on gas transfer. Here the hydration reaction of CO2 is
currently of most interest, because currently only some model computations are available but
no detailed measurements.
4. Analysis of the spatial and temporal structure of the turbulence in the water-sided viscous
boundary layer and close beneath as the driving force for air-water gas exchange.
5. Studies of the intermittency of the transfer processes in order to gain a better insight into the
mechanisms.
6. Synthesis of all this findings in a physically based model the air/sea gas transfer process.
Overarching topic
is the study of small-scale air-sea interaction, especially the mechanisms of air-sea gas exchange and
the dynamics of wind waves.
Background
Despite intensive research, knowledge about air-sea interaction processes has not been significantly
improved during the last decade. Many basic questions are still open and the relation of the air-sea gas
exchange rate with wind speed is discussed controversial. Both field and laboratory experiments show
large deviations up to a factor of two from a simple relation between the wind speed and the gas transfer
velocity [Jähne & Haußecker, 1998; Jähne, 2001]. It is obvious that other parameters, especially waveinduced
near-surface turbulence and surface active films are of importance, but detailed modeling of
these processes is still lacking. Therefore, despite their known significant limitations, semi-empirical
relations between the wind speed and the gas transfer velocity, as established by Liss & Merlivat [1986]
or Wanninkhof [1992], are still the state of the art.

140 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
Another uncertainty in the estimation of transfer velocity is the dependence on the Schmidt number
Sc. It is common to assume that the transfer velocity k is proportional to Sc −1/2 . However, for quite
some time it is known [Jähne, 1980] that the exponent is about 2/3 for a smooth water surface at
low wind speeds and gradually decreases to 1/2 for a rough and wavy water surface. The exact shape
of this transition, and especially how it is influenced by surface films in coastal zones and on which
parameters it depends, is not known. This lack of knowledge causes a considerable uncertainty in
estimating the transfer velocity. A change of the exponent from 2/3 to 1/2 without a change of other
parameters causes an increase of the transfer velocity by about a factor of two.
Recently, the intermittent nature of the gas exchange process has come into the focus of research.
Of particular interest is the microscale wave breaking, a process that causes enhanced near-surface
turbulence. It is known that microscale wave breaking enhances gas transfer. Zappa et al. [2001]
found, e. g., a good correlation between the measured transfer velocity and the fraction of the water
surface at which surface renewal occurred by microscale wave breaking. Details of the mechanisms
that allow a physically-based parameterization are, however, not yet known. The intermittency of the
gas transfer is of much importance when integrating gas transfer rates form short time and spatial
scales as determined by active thermography to larger scales. Because the relation between wind
speed and the transfer velocity and possible other parameters is certainly nonlinear, not only the
mean values but also the variations must be known for a proper integration.
A particularly difficult and interdisciplinary problem is the influence of organic films on air-sea gas
transfer [Frew, 1997]. Surfactants attenuate short wind waves and thus changes the hydrodynamic
boundary conditions at the water surface. In effect, the gas transfer rate is significantly reduced.
Interestingly this complex process can be modeled by simply relating the gas transfer rate to the
mean square wave slope [Frew, 1997; Bock et al. , 1999; Frew et al. , 2004]. This close correlation
between the mean square slope and the gas transfer rate was already pointed out by Jähne et al.
[1987] long before systematic studies of the influence of surface films on gas transfer were performed.
However, a more detailed modeling is still lacking.
Main methods
By using novel visualization techniques and image sequence processing techniques, the complex smallscale
air-sea interaction processes can be tackled experimentally for the first time in both laboratory
and field experiments. Equally important are spectroscopic techniques that allow simultaneous gas
exchange measurements with many tracer. The techniques are briefly described in the following.
UV-spectroscopy for volatile species dissolved in water UV spectroscopy in contrast to IR
spectroscopy offers the significant advantage that it is not required to degas water samples
in order to measure gases and volatile species dissolved in water, because water is transparent
in the required wavelength range from 200–300 nm. Thus this technique can be used to measure
concentrations both the water and air space. The technique adds a number of volatile species for
gas exchange measurements, especially species containing aromatic rings, such as fluorobenzenes,
thiophenes, and pyrenes. For further details see section 5.1.1 and Degreif [2006].
Wave slope and height imaging A detailed investigation of the dynamics of short wind waves
required simultaneous imaging of the wave height and slope. This is because the energy of
gravity waves is contained in the wave height whereas the energy of the capillary waves is
proportional to the wave slope. Therefore a novel instrumentation was developed that is capable
to measure the wave slope and height simultaneously by making use of the fact that light at
different wavelengths in the near infrared shows significant differences in absorption. In this way
the imaging wave slope gauge could be extended for simultaneous wave height measurements
(section 5.1.7 and Jähne et al. [2005]).
Active thermography Using heat as a proxy tracer for gases has two significant advantages. Firstly,
the concentration of the tracer at the water surface can directly be measured with infrared cameras.
Secondly, the heat flux can be controlled by applying infrared radiation onto the water
surface. Periodically varying infrared radiation was applied to the water surface to create a corresponding
variation in the surface temperature of the water. For slow variations of the infrared
radiation - slower than the time constant for the exchange process - the transfer velocity can be
measured directly by dividing the known flux density by the measured temperature variation.
If the heat flux is switched off, the temperature increase will decay with the characteristic time
constant t⋆ (surface renewal time) for the transport process across the aqueous heat boundary
layer. From this time constant the transfer velocity k can be computed directly using the relation
t⋆ = D/k 2 , where D is the diffusion coefficient for heat [Jähne et al. , 1989]. By measuring the

5.1. SMALL-SCALE AIR-SEA INTERACTION 141
phase shift and amplitude damping of the thermal boundary to periodically changing IR radiation,
it is also possible to distinguish between different models for the exchange process and to
investigate the intermittency of the process [Popp, 2006]. Because the infrared image sequences
contain significant contrast, the surface flow field including its vorticity and local convergence
and divergence zones can also be computed from image sequences [Garbe et al. , 2003]. Moreover,
the spatial structure of the micro-turbulence at the water surface can be studied [Schimpf
et al. , 2004].
Fluorescence imaging of gas tracer concentration fields Concentration fields of dissolved gases
in water can be made visible by two techniques. Firstly, oxygen can quench the fluorescence of
dyes with a rather long live time. While previously less suitable dyes such as pyrene butyric
acid were used, a new class of dyes, organic ruthenium complexes are more sensitive, not surface
active and can be dissolved readily in water. Secondly, dyes with a pH-dependent fluorescence
can be used with experiments using acid or alkaline gases or volatile species including carbon
dioxide. While previously fluorescein or derivatives were used, a better alternative was found in
HPTS.
The ultimate goal is the dynamic visualization of three-dimensional concentration fields. One
promising approach is a kind of spectroscopic tomographic technique. It makes use of the fact
that the fluorescence spectrum of dyes generally shows a bandwidth between 30 and 100 nm.
A second dye cab be used to attenuate the emitted fluorescent light in this wavelength range
differently for different wavelengths. With this double-dye technique, the shape of the observed
fluorescence spectrum depends on the path length the light travels through the water before it
is measured. Because the fluorescence is excited from the air space, the path length directly
corresponds to the distance from the water surface. For a given wavelength, the fluorescent
light received is then integrated over a characteristic depth ˆz = α −1 (λ), where α(λ) is the
wavelength-dependent absorption coefficient of the absorbing dye solution. If α(λ) is known,
the depth-dependent concentration can be computed from the measured spectra as a linear
inverse problem.
3-D flow measurements close to and at the water surface The aqueous viscous boundary layer
at a wind-driven water surface has a thickness of at most a millimeter. Therefore almost no flow
measurements are available from this layer at a free water surface. We try to tackle this difficult
experimental problem with two techniques. First, thermal image sequences from the water surface
contain enough structures to computed 2-D flow fields (section ??). Secondly, a modified
particle tracking technique is used for depth-resolved flow measurements. Again an absorbing
dye is used to code the depth of the tracked particles and to measure the velocity component
perpendicular to the water surface from the brightness change of the particle (section 5.1.5).
Main activities
Our current main activities include
1. the development of a novel optic technique for simultaneous imaging of the height and slope of
short wind waves (section 5.1.7),
2. the development of depth-resolving imaging technique to measure concentration fields of gases
close to the water surface by using a double dye laser induced fluorescence techniques (sections
5.1.2 and 5.1.4),
3. detailed studies of the Schmidt number dependency of air-water gas transfer (section 5.1.1),
4. investigations of the air-sea gas exchange by active thermography (section 5.1.6),
5. analysis of flow fields by passive and active thermography thermography (section ??),
6. 3-D flow measurements within the aqueous viscous boundary layer. (section 5.1.5)
Funding
1. DFG-Schwerpunktprogramm 1114 “Mathematische Methoden der Zeitreihenanalyse und digitalen
Bildverarbeitung”
2. DFG-Schwerpunktprogramm 1147 “Bildgebende Strömungsmesstechnik”

142 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
3. Graduiertenkolleg 1114 “Optische Messtechniken für die Charakterisierung von Transportprozessen
an Grenzflächen” (TU Darmstadt and U Heidelberg)
4. DFG Ja395/13: ”Impact of Wind, Rain, and Surface Slicks on Air-Sea CO2 Transfer Velocity -
Tank Experiments”
Cooperation within the institute and with groups outside of the institute
1. Prof. Jürgen Wolfrum, PD Dr. Volker Ebert, Physikalische Chemie, Universität Heidelberg
2. Prof. Dr. Klaus Affeld, Dr. Ulrich Kertzscher, Labor für Biofluidmechanik, Universitätsklinikum
Charite Berlin, Humboldt Universität Berlin
3. Dr. Volker Beushausen, Laser-Laboratorium Göttingen e.V.
4. Prof. Dr. Gerhard Jirka, Dr. Herlina, Institut fr Hydromechanik, TU Karlsruhe
5. Prof. R. Mester, Digitale Bildverarbeitung, Institut für Angewandte Physik, Universität Frankfurt
6. Dr. Bernd Schneider, Dr. Joachim Kuss, Institut für Ostseeforschung, Warnemünde
7. Prof. Christoph Schnörr, Bildverarbeitung, Mustererkennung & Computergrafik Universität
Mannheim
8. Prof. Dr. Detlef Stammer, Dr. Martin Gade, Institut für Meeresforschung, Universität Hamburg
9. Prof. Dr. Douglas Wallace, Chemische Ozeanographie, Leibniz-Institut fr Meereswissenschaften,
Kiel
10. Dr. Nelson M. Frew, Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution
(WHOI), USA
11. Dr. Guillemette Gaulliez, IRPHE - Laboratoire IOA, University of Marseille, Frankreich
12. Prof. Dr. Tetsu Hara, Graduate School of Oceanography (GSO), University of Rhode Island,
USA
Future Work
Future work in the coming year will include laboratory measurements in the Heidelberg Aeolotron,
the Marseille and the Hamburg wind wave facilities. Most of this work will be part of the international
SOLAS initiative funded by the BMBF SOPRAN project. The measurements will combine
gas exchange, wave imaging and flow measurements and modelling efforts. In the further stage also
experiments in the field (Baltic Sea) are planned.
The second focus will be further development of the depth-resolving measurements of concentration
fields and 3-D flow fields within the aqueous viscous boundary layer in our new linear wind/wave
facility.
Peer Reviewed Publications
1. Schimpf et al. [2006b]
2. Garbe et al. [2007]
3. Jähne et al. [2007]

5.1. SMALL-SCALE AIR-SEA INTERACTION 143
Other Publications
1. Garbe et al. [2006a]
2. Falkenroth [n.d.]
3. Jähne [2007a]
4. Jähne [2007b]
5. Jehle & Jähne [n.d.]
6. Jehle & Jähne [2006a]
7. Schimpf et al. [2006a]
Diploma Theses
1. Vogel [2006]
PhD Theses
1. Degreif [2006]
2. Popp [2006]
3. Kraus [2006]
4. Jehle [2006]

144 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
5.1.1 Gas Exchange Measurements: The Transition of the Boundary Conditions
from a Flat to a Wavy Water Surface
Kai Degreif
Abstract Gas exchange measurements in a small circular wind wave tank were performed to reproduce
the transition of the Schmidt number exponent from a flat to a rough and wavy water surface.
The transition begins at unexpectedly low wind speeds and extends over a wide range of wind speeds.
a)
Schmidt number exponent n
0.68
0.66
0.64
0.62
0.6
0.58
0.56
0.54
0.52
0.5
0.48
clean surface 09.10.05
clean surface 10.10.05
clean surface 12.10.05
parameterisation
10 −4
10 −3
10 −2
mean squared surface slope σ 2
s
10 −1
k 600 [cm/h]
b)
100
10
1
0.1
τ−model: k ∝ u * Sc −1/2
Deacon−model: k ∝ u * Sc −2/3
clean surface 09.10.05
clean surface 12.10.05
clean surface 10.10.05
surfactant 02.08.06
parameterised transition
0.1 0.2 0.5
friction velocity u [cm/s]
*
1 2
Figure 5.1: a) Measured Schmidt number exponent n in dependence of the waviness of the water
surface. b) Measured transfer velocities normalised to a Schmidt number Sc = 600. Blue dotted line:
model predictions for a flat water surface, red dotted line: predictions for a rough and wavy water
surface, black dotted line: expected transition for a clean surface as in picture a).
Background The theory of mass transfer at the
air water interface is well understood only for a
smooth and flat water surface as in this case the
boundary conditions are equivalent to mass transfer
to a smooth solid wall. Gas transfer may be
quantified in terms of a “transfer velocity k” in
the following form:
k = u∗w
1
12.2 Sc−2/3
Sc > 60 (5.5)
Herein u∗w is the water side friction velocity, a
quantity that describes the shear stress that is
produced by the wind at the water surface. Sc
denotes the “Schmidt number”, a tracer specific
property that describes the relation of tracer diffusivity
and kinematic water viscosity.
If we assume a rough and wavy water surface,
the boundary conditions have to be changed in
the way that now surface divergences and convergences
are allowed. In the theoretical descriptions
this change results in a drop of the Schmidt number
exponent n from 2/3 to 1/2. To date theoretical
descriptions are unable to predict the transition
between the parameterisations for a smooth
and for a rough water surface.
Methods and results Gas exchange experiments
were performed simultaneously with trace
gases that exhibit different Schmidt numbers. In
a small circular wind wave channel with 1.2 m diameter,
wind speed was increased stepwise to produce
different surface roughness conditions. The
measurement of the Schmidt number exponent
was directly accessible from the ratio of the transfer
rates for the different trace gases (figure 5.1.a).
In figure 5.1.b the transition between the different
parameterisations for a clean water surface can
easily be discerned. In an additional experiment
the production of wind waves was suppressed by
adding a surfactant to the water surface. In this
case the measured data points join the parametrisation
for a smooth water surface until the stability
of the surfactant breaks and waves are generated.
For low wind speeds and friction velocities
the measured transfer velocities are higher than
the theoretical predictions. This is an effect that
is produced by secondary currents due to the annular
geometry of the tank and shows clearly the
limitations of the experimental setup.
Outlook/Future work The transition of the
Schmidt number exponent will be measured in the
larger circular facility in Heidelberg (Aeolotron)
as well as in the linear wind wave tanks in Marseilles
and Hamburg. A new linear setup will be
available in Heidelberg in 2007.
Main publication [Degreif, 2006],

5.1. SMALL-SCALE AIR-SEA INTERACTION 145
5.1.2 Gas exchange rates by LIF imaging of O2 concentration boundary
layer
Achim Falkenroth (Kai Degreif)
Abstract Laser-Induced Fluorescence (LIF) is applied to directly observe and understand the mechanism
of gas exchange in the upper 500 µm boundary layer. The luminescent dye used (Ru-complex)
is sensitive to a given in-situ oxygen concentration that quenches the phosphorescence. The obtained
boundary layer thickness leads to the gas exchange rate that is comparable with other measuring
techniques.
a:
b:
Boundary layer thickness z * (mm)
0.6
0.5
0.4
0.3
0.2
0.1
0
0 2 4 6
Wind speed (m/s)
c:
k 600 (cm/h)
6
5
4
3
2
1
H 2
N 2 O
O 2 water probe
O 2 boundary layer z fit
O 2 boundary layer z e
0
0 1 2 3 4 5 6 7
Wind speed (m/s)
Figure 5.2: a: Time series of one line in 27 s with 185 Hz. b: Boundary layer thickness for O2 invasion
into water using two image processing algorithms. c: Comparison of gas exchange constant k with
other measurements.
Background The difficulty in studying the
inter-phase exchange processes is due to the small
interacting thickness of approximately 30 µm to
1 mm on both sides of a boundary layer z∗. Therefore,
none of the traditional fixed sampling methods
are applicable.
A non invasive optical method using luminescent
dyes is chosen to determine the gas concentration.
Especially phosphorescent dyes are advantageously
sensitive to quenching because of the long
live time of their excitation states. In regions of
high oxygen concentration, the amount of light
emitted will be significantly lower.
Methods and results In a small circular wind–
wave tank, the LIF emission of a laser light sheet
was imaged near the surface. The pixel resolution
was 25 µm/pixel and the time resolution 185 Hz.
From time series like a in the shown figure the
boundary thickness z∗ was calculated. Using the
relation
k = Dox/z ∗
(5.6)
with the diffusivity Dox of oxygen in water, the
gas exchange rate was calculated and compared
with other measurement techniques.
Outlook/Future work Better results for high
wind speeds are expected from the improvement
of the optical path in a new linear tank.
Funding DFG-Research-Training-Group
(Graduiertenkolleg 1114)
Main publication [Falkenroth et al. , 2007]

146 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
5.1.3 Water flow measurements in environmental and biological systems
Participating scientist Christoph S. Garbe
Abstract Novel measurement techniques are developed for accurately determining water flows in
biological and environmental systems. These techniques are closely linked to the development of refined
image processing techniques, making temporally and spatially highly resolved field measurements
feasible.
a) b) c)
z
12
b
0
t1 t2 t3
v(z)
x
Intensity, arbitrary units
c
0
0 50 100 150 200
Distance, arbitrary units
10
8
6
4
2
Flow Velocity FTh [mm/min]
9.0
8.8
8.6
8.4
8.2
8.0
7.8
7.6
Diameter of Xylem
7.4
4 5 6 7 8 9 10 11
Distance from Petiol [cm]
Figure 5.3: In a) the effect of Taylor dispersion due to the flow profile in microfluidics is shown. In
b) intensity structures of active thermography due to the flow profile at the air water interface, and
in c) the found correlation between xylem diameter and flow velocities.
Background The transport of energy, mass and
momentum are important quantities in describing
complex system, such as those encountered in engineering,
environmental and life sciences. Systems
of interest are turbulent transport at water
surfaces for air sea heat and gas exchange, water
flow in plant leaves, and microfluids. Density
distributions of tracers are visualized with modern
cameras and their motion as well as density
changes estimated from digital image processing
techniques. Examples of such tracers are heat
which can be applied with lasers and visualized
with highly resolved thermographic imagers or
caged dyes for microfluidic applications. Results
of these flow measurements can be used for modelling
physical transport processes, deepening our
understanding of the systems analyzed.
Funding Research Centre Jülich (Forschungszentrum
Jülich), Jülich
DFG SPP 1147, “Bildgebende Messverfahren für
die Strömungsanalyse”
DFG SPP 1114, “Mathematische Methoden
der Zeitreihenanalyse und digitalen Bildverarbeitung”
Methods and results A fluid is visualized using
density distributions as tracers. These can be
heat or dyes. At the air-water interface, usually
a net heat flux is present which allows visualizing
turbulences directly without additional tracers.
The motion of density distributions is then
modelled as a linear partial differential equation
(PDE). These PDEs can be solved from the image
sequences with techniques developed in digital image
processing. This allows to estimate the motion
Flow Velocity
as well as density changes in the image sequences.
Novel motion models have been developed that
allow to explicitly model velocity gradients of the
fluid flow and the physical transport phenomena.
In microfluidics, this makes it feasible to measure
fluid flow accurately in the presence of Taylor dispersion.
At the shear driven free water interface,
a similar technique can be adapted to measure
not only the flow velocity directly at the interface,
but the flux of momentum from air to water.
From thermography, both the flux of momentum
as well as that of energy can be measured with
the same experimental set-up in the same footprint
directly at the interface. This opens up new
possibilities for better understanding and parameterizing
transport across the water-air interface.
Outlook/Future work The developed techniques
will be used for studying transport processes
for shear driven as well as convective driven
exchange of heat and mass at the air-water interface,
both in laboratory setting as well as in
the field. Furthermore, the transport of Xylem
in plant leaves will be measured under varying
environmental forcings. This will make spatially
resolved measurements of water flows in plant
leaves possible for the first time, closing a missing
link in the understanding of water relations in
plants. In microfluidic mixing machines, together
with species concentrations from Raman scattering,
low Reynolds number flows will be measured.
This will improve the design and mixing capabilities
for such devices.
Main publication Garbe et al. [2006c,b]
2.0
1.8
1.6
1.4
1.2
1.0
Diameter DnX [mm]

5.1. SMALL-SCALE AIR-SEA INTERACTION 147
5.1.4 Measuring depth dependent concentration profiles via fluorescent
pH-indicator
A. Herzog
Abstract A new wind wave flume is built in order to investigate penetration of acid/alkaline gases
from air into the water phase through the air-water boundary layer.
Figure 5.4: left image: example of calibration curve emission intensity over pH-value; right image:
penetration of acid gases -dark eddies- into a dye solution in the alkaline range illuminated by a Laser
from above.
Background In environmental physics gas exchange
is of high importance regarding the damping
of CO 2 in the oceans, which is a crucial factor
in the prediction of world climate.
Each available model of gas exchange prognoses
a different depth-dependent gas concentration
within the water-sided boundary layer between air
and liquid phase. Yet, until now it was not possible
to measure this concentration directly and
therefore distinguish between the models.
It is known that molecular diffusion determines
the actual transition of gas molecules into the
skin of the boundary layer and turbulent processes
dominate the transport into deeper layers. But
the kind of turbulent processes that take place is
still under investigation, e.g. ?. In general, this
work continues with the project of ? and is closely
related to the work of ?.
Methods and results In this work the depthdependent
gas concentration is examined by
LASER induced fluorescence (LIF). This means
fluorescence dyes are used which indicate the presence
of different gases via a change in intensity of
fluorescene.
In detail a fluorescent pH-indicator for detection
of alkaline/acid gases like CO 2 is used. For
the present setup the experiment starts with a
dye solution in the alkaline range, where fluorescence
intensity is highest. Penetrating acid gases
diminuish the fluorescence intensity and are therefore
visible to a CCD-camera setup.
Titration experiments have been carried out to
obtain calibration curves, grey value and therefore
emission intensity as a function of conductivity or
pH-value. The result of one of these is plotted
in the figure above. Especially around the first
point of neutralization the intensity is extremely
sensitive to changes in the conductivity/pH-value
(high slope). So penetrating acid gases appear as
areas of lesser fluorescence intensity. In that way
not only the gas concentration can be determined
locally but also the transport mechanism in the
forms of turbulent currents and eddies, which can
be seen in the right image above.
As the boundary layer size varies between 30 -
300 µm the demands on optical properties are
extremly high.
Currently a new linear wind-wave-flume is being
built with better optical properties that is also
able to deal even with strong acid/alkaline gases
like HCl. The old circular facility was regretably
not able to fullfill the needs of the used technique.
Outlook/Future work The new flume will be
finished within the next month. After instrumentation
is sucessfully completed the main measurements
can begin in the first months of next year.
Funding This project is supported by the DFG
via the GRK 1114 -’Optische Messtechniken für
die Charakterisierung von Transportprozessen an
Grenzflächen’.
Main publications [Herzog, n.d.]

148 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
5.1.5 3D fluid flow measurement close to free water surfaces
Markus Jehle
Abstract A novel measurement technique is developed for 3D reconstruction of velocity vector fields
close to free water surfaces. The new method overcomes the restriction of planar dimensionality by
both a sophisticated experimental setup and data analysis based on contemporary image processing
techniques.
1.5
1
0.5
0
-0.5
-1
-1.5
0 0.5 1
z = 9.5mm z = 7.5mm z = 5.5mm
z = 3.5mm z = 1.5mm z = 0.5mm
umean/vmean [pixel/frame] urms/vrms [pixel/frame] wmean [cm/frame] wrms [cm/frame]
0.8
0.6
0.4
0.2
0.01
0.005
0
-0.005
0
-0.01
0
z[cm] 0 0.5 1 z[cm] 0 0.5 1 z[cm] 0 0.5 1 z[cm]
Figure 5.5: Flow in a convection tank driven by buoyancy and evaporation. Top: Velocity vector
fields starting from the deepest layer moving upwards (the w-component is colour-coded). Bottom:
Vertical profiles of the mean and rms velocities (red: u, blue: v, black w).
Background In order to examine the air-water
gas exchange a detailed knowledge of the waterside
flow-field is needed. Therefore important
quantities such as shear stresses and velocity profiles
have to be determined. Because the interesting
flow is 3D, instationary and close to the wavedriven
water-surface, conventional techniques like
particle imaging velocimetry (PIV) using laser
light sections are not applicable. A technique,
that is similar to the one proposed here, is applied
in the field of biofluidmechanics successfully,
where it is important to get knowledge about the
flow in artificial blood vessels.
Methods and results A fluid volume is illuminated
by LEDs. Small spherical particles are
added to the fluid, functioning as a tracer. A
camera pointing to the water surface from above
records the image sequences. The distance of the
spheres to the surface is coded by means of a
supplemented dye, which absorbs the light of the
LEDs according to Beer-Lambert’s law. By using
LEDs flashing with two different wavelengths, it
is possible to use particles variable in size. The
0.025
0.02
0.015
0.01
0.005
velocity vectors are obtained by using an extension
of the method of optical flow, an established
technique in computer vision. The vertical velocity
component is computed from the temporal
change of brightness.
Hardware and algorithmics are tested in several
ways: i) A laminar falling film serves as reference
flow. The predicted parabolic profile of this
stationary flow can be reproduced very well. ii)
Convective turbulence acts as an example for an
instationary inherently 3D flow (see figure 5.5).
Outlook/Future work The presented technique
constitutes the first part of a comprehensive
research project whose ultimate goal is the
spatio-temporal analysis of flows close to moving
and wave-driven curved interfaces.
Funding DFG priority program “Bildgebende
Messverfahren für die Strömungsanalyse”.
Main publications [Jehle & Jähne, 2006b;
Jehle, 2006; Jehle et al. , in preparation]

5.1. SMALL-SCALE AIR-SEA INTERACTION 149
5.1.6 Small-scale turbulence in the sea-surface microlayer
Uwe Schimpf
Abstract Heat is used as a proxy tracer for gases to study the transport processes across the seasurface
microlayer. Infrared imaging techniques permit fast measurements of heat transfer velocities
and give an insight into the transport mechanisms across the thermal sublayer.
IR camera
(3-5 µm)
240 Watt carbon dioxide
laser (10.6 µm)
optics
wind wave facility
mirror
x-y
scan
head
wind speed: 2.0 ms
0.5 s 1.0 s 1.5 s
2.0 s 2.5 s 3.0 s
wind speed: 7.0 ms
0.5 s 1.0 s 1.5 s
2.0 s 2.5 s 3.0 s
Figure 5.6: Setup of the controlled flux technique in the wind-wave facility at IRPHE, University of
Marseille. The carbon dioxide laser forces a periodically varying heat flux onto the water surface. The
temperature response of the water surface (amplitude and phase shift) is measured by an infrared
imager.
Background The turbulent mixing processes in
the watersided thermal boundary layer controlling
the transport of heat across the sea surface microlayer
are investigated with high temporal and
spatial resolution by means of the active controlled
flux technique [Jähne et al. , 1989].
Methods and results The heat flux density is
controlled by forcing infrared radiation onto the
water surface and the variation of surface temperature
is measured with an infrared camera.
For slow temporal variations of the infrared radiation
the heat transfer rate is given by the ratio
of the net heat flux density and the temperature
change at the water surface. If the heat flux is
switched off, the temperature increase will decay
with a characteristic time constant of the transport
across the thermal sublayer. The measured
phase shifts clearly indicate that the transfer process
is strongly intermittent.
Outlook/Future work The improved ACFT
system was deployed for 4 weeks in wind-wave facility
at IRPHE, University of Marseille. A detailed
comparison of the local heat transfer and
the synchronously measured surface slope of short
wind waves (section 5.1.7) might allow to identify
micro scale breaking of capillary waves.
Funding Aktives Thermografie System, HBFG-
125-667 (Hardware), DFG Ja395/13-1 (Joint
project with Institut für Meereskunde, Universität
Hamburg.
Main publications [Schimpf et al. , 2006b],
[Schimpf et al. , 2006a]

150 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
5.1.7 Measurement of short wind waves
Roland Rocholz
Abstract Imaging systems for the measurement of short wind waves were set up at two wind-wave
facilities 1,2 . The synchronized measurement of the water surface structure and the heat flux (see also
section 5.1.6) was tested during two gas–exchange experiments. The work on an automated calibration
for the Heidelberg setup has been continued.
a b
Figure 5.7: a Example of wave imaging that color–codes the water surface gradient. (Raw image,
image sector: 40 cm x 30 cm) b Top view of the robot for calibration. Three spindles press a glass
window below the water surface. Thus defined inclinations of the water–glass–air interface can be
used to calibrate the imaging setup.
Background Measuring wind waves is of special
interest for air–sea gas and heat transfer investigations.
We aim at a better understanding of
the wave influence on the turbulence near the water
surface. This turbulence in the viscous boundary
layer is responsible for enhancing the exchange
of heat and trace gases. Especially the breaking of
small–scale waves is suspected to contribute significantly
to this enhancement [Csanady, 1990].
Synchronized imaging of waves and heat flux on
the water surface provides a direct visualization
for this process, see also section 5.1.6. So far it
is only possible to perform these measurements in
the laboratory. We conduct experiments in different
wind–wave tanks to investigate the reproducibility
of the observations under different geometries
given by the tanks. This is important to
allow for inference to the physical processes at the
open sea.
Methods and results The applied wave imaging
is based on light refraction. The water surface
is observed by an digital camera from above and is
illuminated by an area-extended light source from
below. A defined spatial variation of radiance or
color allows for tracing the rays from the image
plane back to the light source. From this, the surface
gradient can be computed using the law of refraction.
For experiments in Marseille (11/2006),
two color cameras were used to double the sample
rate up to 400 images per second. In addition,
the cameras were synchronized with the system
for active thermography that gives the heat flux
1 Wind–wave flume of the Institut für Meereskunde, University of Hamburg, Germany
2 Wind–wave flume at IRPHE, University of Marseille, France
information. As light source a sealed box with 20
neon tubes was put directly into the water. Color
coding was gained with the use of a colored transparent
film. Figure 5.7a shows an example for the
wave images. Sequences at wind speeds of 10, 8,
5, 3, and 2 m/s were captured. For test experiments
in Hamburg (04/2006) an array consisting
of 320 LEDs was used as light source. In this case
the radiance is regulated to achieve spatial variation
of monochromatic light. The light source is
located beneath the water body. This allows for
the application of a telecentric illumination setup
[Rocholz, 2005]. The setups still need further improvements
to achieve the aimed accuracy. For
the calibration of the wave imaging system a robot
was build which is currently tested, see fig. 5.7b.
Outlook/Future work Based on the evaluation
of the Marseille experiments, we will conduct
constitutive experiments in Hamburg (04/2007).
Setup modifications and calibration tests are
planned to improve the performance of the system.
The combined analysis of synchronized wave
and heat information is expected to give new insight
into the microscale wave breaking process.
Main publication [Rocholz, 2005], [Rocholz,
2006]
Funding DFG, Ja395/13: ”Mechanismen des
Gasaustausches zwischen Atmosphäre und Ozean:
Laborversuche und Modellierung”

5.1. SMALL-SCALE AIR-SEA INTERACTION 151

152 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
5.1.8 Spectroscopic Techniques for Gas-Exchange Measurements
Felix Vogel
Abstract To evaluate the applicability of different spectroscopic techniques for temporally resolved
gas-exchange measurements a Raman spectometer was built and existing UV/Vis systems were improved.
Laboratory experiments yielded that Raman spectroscopy is not suitable for dynamic gasexchange
measurements due to its insufficient temporal resolution while the applicability of UV/Vis
spectroscopy was confirmed.
Figure 5.8: Simultaneous measurement of the concentration of anisole in the air and water-bulk during
an invasion experiment
Background Studying gas-exchange processes
contributes to the understanding of our climate
system as well as it is fundamental research of
turbulent processes in fluids.
Accounting for small scale processes to yield an
accurate parametrisation of the transfer rate, temporally
resolved in-situ measurements of the concentration
change have to be performed.
Besides classical methods measuring dissolved
gases, recently temporally highly resolved spectroscopic
techniques with volatile aromatics have
been introduced as a new tool for the investigation
of the transfer processes [Degreif2006].
Funding None
Methods and results Experiments with pure
and dissolved aromatics yielded that the newly
built Raman setup is not suitable for systemanic
gas-exchange measurements. To conduct experiments
at the circular wind-wave flume of the University
of Heidelberg and the linear wind-wave
flume of the University of Hamburg, one waterphase
and one air-phase setup was developed. The
performance of both UV/Vis spectrometers was
evaluated at the Aeolotron laboratory. With an
absorption path length of up to 10 metres the
temporal resolution of the air-phase spectrometer
is of the order of deciseconds. Invasion experiments
yielded that the in-situ concentration
can be monitored continuously in the range of
30 ppm−0.3 ppm for example for benzaldehyde.
For the UV/Vis setup to measure the water-phase
concentration an absorption length of one metre
and an integration time of 40 ms turned out to be
adequate.
Outlook/Future work To reduce the uncertainties
of the calculated piston velocities, the solubilities
of the applied substances should be determined
in laboratory experiments, as the values
given in the available literature vary largly. The
acquistion of concentration gauged spectra is also
needed to determine the piston velocities of moderately
soluble substances. As their transfer rate
is not dominated by the transfer rate of one compartment,
both air and water-phase concentration
have to be taken into account.
Main publications [Vogel, 2006]

5.1. SMALL-SCALE AIR-SEA INTERACTION 153
References
Bock, E. J., Hara, T., Frew, N. M., & McGilles, W. R. 1999. Relationship between air-sea gas transfer
and short wind waves. J. Gephys. Res., 104, 25 821–25 831.
Csanady, G.T. 1990. The role of breaking wavelets in air–sea gas transfer. J. Geophys. Res., 95,
749–759.
Degreif, K. A. 2006. Untersuchungen zum Gasaustausch - Entwicklung und Applikation eines zeitlich
aufgelsten Massenbilanzverfahrens. PhD Thesis, Universität Heidelberg.
Falkenroth, A.; Herzog, A.; Jähne B. Visualization of Air Water Gas Exchange using Novel Fluorescent
Dyes. ISFV 12, 10- 14 September 2006, Göttingen.
Falkenroth, Achim, Degreif, Kai, & Jähne, Bernd. 2007. Visualisation of Oxygen Concentration
Fields in the Mass Boundary Layer by Fluorescence Quenching. In: Garbe, C.S., Handler, R.A., &
Jähne, B. (eds), Transport at the Air Sea Interface - Measurements, Models and Parameterizations.
Springer.
Frew, N. M. 1997. The role of organic films in air-sea gas exchange. Pages 121–172 of: Liss, Peter S., &
Duce, Robert S. (eds), The Sea Surface and Global Change. Cambridge, UK: Cambridge University
Press.
Frew, N. M., Bock, E. J., Schimpf, U., Hara, T., Haußecker, H., Edson, J. B., McGillis, W. R., Nelson,
R. K., McKeanna, B. M., Uz, B. M., & Jähne, B. 2004. Air-sea gas transfer: its dependence on wind
stress, small-scale roughness and surface films Small-Scale Air-Sea Interaction with Thermography.
J. Geophys. Res, C8(109). C08S17, doi:10.1029/2003JC002131.
Garbe, C. S., Roetmann, K., & Jähne, B. 2006a. An Optical Flow Based Technique for the Non-
Invasive Measurement of Microfluidic Flows. Pages 1–10 of: 12TH INTERNATIONAL SYMPO-
SIUM ON FLOWVISUALIZATION.
Garbe, C. S., Roetmann, K., & Jhne, B. 2006b. An Optical Flow Based Technique for the Non-
Invasive Measurement of Microfluidic Flows. Pages 1–10 of: 12th International Symposium on
Flow Visualization.
Garbe, C. S., Degreif, K., & Jhne, B. 2006c. Viscous stress measurements from active thermography
on a free air-water interface. Pages 1–10 of: International Symposium on Transport at the Air-Sea
Interface.
Garbe, C. S., Handler, R. A., & Jähne, B. 2007. Transport at the Air Sea Interface - Measurements,
Models and Parameterizations. Springer. Accepted for publication.
Garbe, Christoph S., Spies, Hagen, & Jähne, Bernd. 2003. Estimation of Surface Flow and Net Heat
Flux from Infrared Image Sequences. J. Mathematical Imaging and Vision, 19, 159–174.
Herzog, A. Tiefenaufgelöste Grenzschichtvisualisierung an freien Oberflächen.
Jähne, B. 1980. Zur Parameterisierung des Gasaustausches mit Hilfe von Laborexperimenten. PhD
Thesis, Universität Heidelberg. D-200.
Jähne, B. 2001. Air-Sea Interaction: Gas Exchange. In: Steele, J., Thorpe, S., & Turekian, K. (eds),
Encyclopedia of Ocean Sciences. Academic Press, London.
Jähne, B. 2007a. Complex Motion. Springer. LNCS 3417.
Jähne, B. 2007b. Complex Motion in Environmental Physics and Live Sciences. Pages 92–105 of:
Jhne, B. (ed), Complex Motion. Springer. LNCS 3417.
Jähne, B., & Haußecker, H. 1998. Air-Water Gas Exchange. Annual Rev. Fluid Mech., 30, 443–468.
Jähne, B., Münnich, K. O., Bösinger, R., Dutzi, A., Huber, W., & Libner, P. 1987. On the parameters
influencing air/water gas exchange. J. Geophys. Res, 92, 1937–1949.
Jähne, B., Libner, P., Fischer, R., Billen, T., & Plate, E. J. 1989. Investigating the transfer processes
across the free aqueous viscous boundary layer by the controlled flux method. Tellus, 41B, 177–195.

154 CHAPTER 5. SMALL-SCALE AIR-SEA INTERACTION
Jähne, B., Schmidt, M., & Rocholz, R. 2005. Combined optical slope/height measurements of short
wind waves: principle and calibration. Meas. Sci. Technol., 16, 1937–1944.
Jähne, B., Popp, C., Schimpf, U., & Garbe, C. S. 2007. The Influence of Intermittency on Air/Water
Gas Transfer Measurements. In: Garbe, C.S, Handler, R. A., & Jhne, B. (eds), Transport at the Air
Sea Interface-Measurements, Models and Parameterizations. Springer. Accepted for Publication.
Jehle, M. 2006. Spatio-temporal analysis of flows close to water surfaces. PhD Thesis, Universität
Heidelberg.
Jehle, M., & Jähne, B. A novel method for spatio-temporal analysis of flows close to free water
surfaces. Experiments in Fluids, Special Issue for ISFV12.
Jehle, M., & Jähne, B. 2006a. Direct estimation of the wall shear rate using parametric motion models
in 3D. In: Pattern Recognition, 28th DAGM.
Jehle, M., & Jähne, B. 2006b. A novel method for spatiotemporal analysis of flows within the waterside
viscous boundary layer. In: 12th International Symposium of Flow Visualisation.
Jehle, M., Klar, M., & Jähne, B. in preparation. Optical-Flow based velocity analysis. In: Tropea, C.,
Foss, J., & Yarin, A. (eds), Springer Handbook of Experimental Fluid Dynamics. Berlin, Heidelberg:
Springer.
Kraus, S. 2006. Entwicklung eines flexiblen Softwaresystems zur Auswertung spektroskopischer
Satelliten-Bildsequenzen. PhD Thesis, Technische Informatik, Universität Mannheim.
Liss, P. S., & Merlivat, L. 1986. Air-sea gas exchange rates: introduction and synthesis. Pages 113–127
of: Buat-Menard, P. (ed), The Role of Air-Sea Exchange in Geochemical Cycling. Dordrecht, The
Netherlands: Reidel.
Popp, C. J. 2006. Untersuchung von Austauschprozessen an der Wasseroberfläche aus Infrarot-
Bildsequenzen mittels frequenzmodulierter Wärmeeinstrahlung. PhD Thesis, Universität Heidelberg.
Rocholz, A. 2005. Bildgebendes System zur simultanen Neigungs- und Höhenmessung an kleinskaligen
Wind-Wasser-Wellen. diploma thesis, Universität Heidelberg.
Rocholz, Roland. 2006. Imaging System for combined slope/height measurements of short wind
waves : ISHG. In: DPG Frhjahrstagung, Heidelberg, 03.2006 (ed), Verhandlungen der Deutschen
Physikalischen Gesellschaft. Deutsche Physikalische Gesellschaft.
Schimpf, U., Garbe, C. S., & Jähne, B. 2004. Investigation of transport processes across the sea-surface
microlayer by infrared imagery. J. Geophys. Res, C8(109). C08S13, doi:10.1029/2003JC001803.
Schimpf, U., Popp, C., & Jähne, B. 2006a. Active Thermography: a local and fast method to
investigate heat and gas exchange between ocean and atmosphere. In: DPG Frhjahrstagung, Heidelberg,
15.-17.03.2006 (ed), Verhandlungen der Deutschen Physikalischen Gesellschaftt. Deutsche
Physikalische Gesellschaft.
Schimpf, U., Frew, N., & Jähne, B. 2006b. Infrared Imaging: A novel tool to investigate the influence
of surface slicks on air sea gas exchange. In: Gade, M., Hühnerfuss, H., & Korenowski, G.M. (eds),
Marine Surface Films: Chemical Characteristics, Influence on Air-Sea Interactions, and Remote
Sensing. Springer.
Vogel, F. 2006. Raman- and UV-Spectroscopy of liquids and dissolved volatile gases for gas-exchange
measurements. diploma thesis, Universität Heidelberg.
Wanninkhof, R. 1992. Relationship between wind speed and gas exchange over the ocean. J. Gephys.
Res., 97, 7373–7382.
Zappa, C. J., Asher, W. E., Jessup, A. T., Klinke, J., & Long, S. R. 2001. Effect of microscale wave
breaking on air-water gas transfer. Pages 23–29 of: Donelan, M. A., Drennan, W. M., Saltzman,
E. S., & Wanninkhof, R. (eds), Gas Transfer at Water Surfaces. Geophysical Monograph, vol. 127.
Washington, DC: American Geophysical Union.

Forschungsstelle “Radiometrie” of
the Heidelberger Akademie der
Wissenschaften
6.1 Forschungsstelle ”Radiometrie” of the Heidelberger Akademie der Wissenschaften
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
155

6.0. FORSCHUNGSSTELLE “RADIOMETRIE” 157
6.1 Forschungsstelle ”Radiometrie” of the Heidelberger Akademie
der Wissenschaften
Augusto Mangini
The Forschungsstelle is an independent research unit funded by the Heidelberger Akademie der Wissenschaften.
Founding began in the year 1958 will run through the end of 2010.
Group members
Prof. Dr. Augusto Mangini
Dr. Bernd Kromer
R. Eichstätter, technician
M. Gillmann, technician
K. Thomas, Secretary
Additional funding from the DFG, BMBF and EU:
Dr. H. Braun, Post Doc
Dr. M. Friedrich, Post Doc
Dr. D. Scholz, Post Doc
Dr. A. Schröder-Ritzrau, Post Doc
Dr. I. Unkel, Post Doc
Dr. P. Verdes, Post Doc
S. Talamo, Scientific staff
F. Bernsdorff, PhD-student
J. Fohlmeister, PhD-student
C. Mühlinghaus, PhD-student
N. Latuske, PhD-student
J. Lippold, PhD-student
D. Schimpf, PhD-student
N. Vollweiler, PhD-student
H. Baus, technician
E. Gier, technician
S. Kühr, technician
S. Lindauer, technician
4 student assistants
The task of the Forschungsstelle ”Radiometrie” of the Heidelberger Akademie der Wissenschaften is
dating and interpretation of climate archives. The research unit presently consists of two groups, the
Radiocarbon Lab (Bernd Kromer) and the Th/U-Lab (Augusto Mangini).
14 C Lab The focus of the 14 C Lab are highly precise 14 C-dating and the construction of a calibration
curve for radiocarbon that reaches far back into the last Glacial. Furthermore this Lab delivers 14 Cdatings
for several archeological groups.
Methods We use both the conventional gas-counting technique and AMS. The gas counters were
developed to highest precision (better than 2 permille). For AMS we prepare graphite targets, to be
measured at one of the European AMS facilities.
Extension of tree-ring based 14 C calibration into the Late Glacial In collaboration with
the tree-ring laboratories of the University Stuttgart-Hohenheim and the University of Zürich/WSL
Birmensdorf we extend the tree-ring based 14 C calibration into the past. Presently the absolutely
(annually) dated oak and pine chronology starts at 12.400 years BP (before AD 1950) [Friedrich et al.
, 2004; Reimer et al. , 2004]. In the Late Glacial two independent chronologies were built in the two
tree-ring labs, assisted be numerous 14 C predating in our laboratory [Kromer et al. , 2004; Schaub
et al. , 2005]. Based on a comparison to the marine 14 C of Hughen et al. [2004] the chronologies
cover the mid-Bølling, all of Allerød and the initial 150 years of Younger Dryas (ca. 14.100 to 12.800

158 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
cal BP). The trees were recovered from gravel pits at the Danube river and its tributaries, the lignite
area south-east of Berlin, and construction sites in Zürich. Beyond the range of these chronologies we
assembled several floating 14 C sections from trees found in Northern Italy and Romania. The 14 C data
sets are evaluated to infer solar activity variability [Bond et al. , 2001; Solanki et al. , 2004; Usoskin
& Kromer, 2005; Usoskin et al. , 2006] as well as ocean thermohaline circulation changes. Combined
with 10 Be time series from Greenland they may serve to link tree-ring and ice-core time-scales.
From dendro-climatological parameters of tree-rings, such as ring-widths, frost damage and growth
patterns climate anomalies can be reconstructed.
14 C dating, archaeology and geosciences We maintain extensive collaborations with archaeologists
to date key sites, such as Troy [Kromer et al. , 2002] or the Nasca sites in Peru [Eitel et al.
, 2005], and to anchor floating tree-ring sections by 14 C wiggle-matching to the absolute scale. In
the ’Roman Gap Project’ (http://www.arts.cornell.edu/dendro/2004News/ADP2004.html) we assist
in the extension of the Eastern Mediterranean chronologies into the first millennium AD, to link the
absolute part to the 2300-year long Bronze Age chronology [Manning et al. , 2003]. The date of the
eruption of Thera remains a crucial and still controversial time marker of the Late Bronze Age in the
Eastern Mediterranean. In long-standing collaborations with colleagues in archaeology we contribute
to a high-precision 14 C date of this event [Manning et al. , 2001].
14 C in the present-day carbon cycle The present-day 14 C level is largely determined by the
re-equilibration of the atmosphere following strong 14 C input during the bomb testing up to 1962,
and the dilution of the natural 14 C level by anthropogenic, 14 C free, CO2 emissions (see contribution
by I. Levin in this report). In our laboratory continuous 14 C times series from several sites around
the globe have been measured up to today, now covering more than 40 years [Levin & Kromer, 2004].
Recently 14 C has become an important marker to determine the ratio of fossil to present-day sources
of carbon, e.g. in the emissions trading. Here we are involved in pilot studies to establish legislative
procedures.
Th/U-Lab The Th/U-Lab works on continental archives, such as speleothems and travertines, as
well as on marine samples, such as deep sea sediments, Mn-nodules and corals.
One principal focus is the determination of the natural variations of climate in the past (from the
Holocene to the Last Pleistocene) using the stable isotope composition of speleothems. Further, we
determine the height of the sea level in the past from the position and ages of fossil coral reefs as well
as the intensity of the Earths magnetic field during the past 350,000 years.
These studies deliver a precise time scale for the variations of climate in the past, which is a basic
requirement for understanding the mechanisms behind the larger abrupt climate changes during the
past 350,000 years, as well as for the causes of the minor climate changes during the Holocene. We
work in close cooperation with climate modelers from Hamburg and Berlin in the DEKLIM program (
through 5/2006), and with modelers from Potsdam where their CLIMBER2 model is applied to study
the abrupt climate changes that occurred during the last Glacial (Dansgaard/Oeschger events).
Methods We use a number of methods for dating, relying on the disequilibrium of the natural decay
chains (TIMS- 230 Th/U-, 231 Pa/U), and on the decay of 10 Be, a radioactive product of cosmic rays.
Speleothems, an archive of paleoclimate Stalagmites are being developed as climate archives
because they can be dated very precisely with the Th/U method, and because stable isotopes in
the carbonate that can be measured at a resolution of 100 µm (corresponding to yearly resolution)
contain a climate signal. Most stalagmites, display significant kinetic effects in the isotope signals.
Since about ten years these kinetic signals in stalagmites were related to the intensity of precipitation.
For example, for speleothems from Oman and from Central Germany, periods of enhanced kinetic
were ascribed to periods of less intense precipitation [Burns et al. , 2002; Fleitmann et al. , 2003; Neff
et al. , 2001; Niggemann et al. , 2003].
This proxy for precipitation with a high resolution combined with the precise Th/U dating lead to
a number of internationally regarded publications. For example we found a very good correlation
between the intensity of precipitation in Oman and the intensity of solar irradiation [Neff et al. ,
2001]. This relationship has been confirmed by a number of following studies. In November 2005
we were granted by the DFG for a Forschergruppe (www.fg-Daphne.de) to study the kinetic effects
in speleothems and their applicability as archives for precipitation and temperature in the past. In
this project, lasting for the next 6 years, we work in close collaboration with groups in Trento, Italy,
Innsbruck, Austria and from Bochum University.

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 159
The intensity of the Earth’s magnetic field in the past Accumulating evidence suggests that
solar activity is responsible for at least some climatic variability. These include correlations between
solar activity and either direct climatic variables or indirect climate proxies over time scales ranging
from days to millennia [Eddy, 1976; Labitzke & Loon, 1992; Svensmark & Friis Christensen, 1997;
Soon et al. , 2000; Beer et al. , 2000; Hodell et al. , 2001]. A very notable correlations was that
obtained in our group in Heidelberg [Neff et al. , 2001]. However, the climatic variability attributable
to solar activity is larger than could be expected from the typical 0.1% changes in the solar irradiance
observed over the decadal to centennial time scale [Beer et al. , 2000; Soon et al. , 2000]. Thus, an
amplifier is required unless the sensitivity to changes in the radiative forcing is uncomfortably high.
The first suggestion for an amplifier of solar activity was suggested by Ney [1959], who pointed out
that if climate is sensitive to the amount of tropospheric ionization, it would be sensitive the intensity
of the Earths magnetic field as well as to solar activity since the solar wind modulates the cosmic ray
flux (CRF), and with it, the amount of tropospheric ionization [Ney, 1959].
We are studying 10 Be in marine sediments to determine the timing and the intensity of the Earths
magnetic field in the past. The cosmogenic nuclide 10 Be is mainly produced in the lower stratosphere
by interaction of galactic cosmic rays with oxygen and nitrogen atoms, and its production is known
to be strongly anti-correlated with the solar- and/or geomagnetic field strength. In addition, highly
resolved profiles of 10 Be in marine sediments may be used to synchronize the marine to the ice core
ones.
Cooperation within the institute and with groups outside of the institute
Peer Reviewed Publications
1. Björck et al. [2006]
2. Braun et al. [2005]
3. Claussen et al. [2006]
4. Frank et al. [2006]
5. Friedrich et al. [2006]
6. Frisia et al. [2006]
7. Kilian et al. [2006]
8. Manning et al. [2006]
9. Scholz & Mangini [2006]
10. Spötl et al. [2006]
11. Spötl & Mangini [2006]
12. Usoskin et al. [2006]
13. Vollweiler et al. [2006]
Other Publications
1. Spötl & Mangini [2005]
Diploma Theses
1. Mühlinghaus [2006]
2. Vollweiler [2005]

160 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
PhD Theses
1. Braun [2006]
2. Latuske [2006]
3. Unkel [2006]

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 161
6.1.1 Modelling growth and isotopic composition of stalagmites
Christian Mühlinghaus (Participating scientist: Denis Scholz)
Abstract Growth and isotopic composition of stalagmites are influenced by climate driven parameters.
To understand the underlying mechanisms, we developed a time dependent multi box model to
calculate growth and the isotopic enrichment of δ 13 C under disequilibrium conditions, both along the
growth axis and individual growth layers of stalagmites.
δ �� �����
2 ,5 -2 ,5 -5 ,0 -7 ,5 -1 0 ,0
δ �� � ����
������������
������� �������
�������
φ 1
1 ,0
0 ,8
0 ,6
0 ,4
0 ,2
0 ,0
0 ,0
������������������������
0 ,1
Figure 6.1: Growth and isotopic enrichment of δ 13 C along the growth axis with varying external
parameters. Stage 1 : dT = 100s – 1000s – 500s, Stage 2 : T = 1 ◦ C – 20 ◦ C – 10 ◦ C, Stage 3 : φ1 = 0.1
– 1.0 – 0.5
Background To reconstruct past variations in
Earth’s climate, a variety of climate archives are
studied. During the last decades stalagmites came
into focus due to their long, continuous growth
periods and improved dating techniques. In this
study a new multi box model is introduced to calculate
time dependent processes in the solution
layer like growth and isotopic enrichment of δ 13 C.
Hereby, we focus on fractionation in disequilibrium,
modelled by a kinetic Rayleigh process. The
dependency of the isotope enrichment of δ 13 C on
external parameters like temperature T , drip interval
dT (i.e. the time between two drops) and
mixing coefficient φ1 is investigated.
Methods and results During CO2 degassing
and calcite precipitation from the solution layer
on top of the stalagmite, the isotopic composition
of the solution and, thus, of the precipitated calcite
changes. This process can be described by a
Rayleigh process, if precipitation occurs under disequilibrium
conditions. To describe this temporal
development of the isotopic change, the movement
of the solution layer has to be known.
Model set-up By fixing the size of the drop volume
and film thickness, boxes are constructed to
divide the solution layer into individual attached
parts. Assuming a stagnant film, the solution
moves between boxes only, if a new drop hits
the innermost box. Therefore, the movement of
the solution becomes dependent on drip interval
and, thus, on time. In addition, mixing processes
must be considered, both between the falling drop
�
��
����������
and the innermost box and among the boxes, described
by mixing coefficients φi.
Calibration The calibration of these mixing coefficients
is realized by a comparison to an existing
stalagmite growth model. By iterative adjustment
of the box model to the reference model the mixing
parameters are optimized.
Fractionation under disequilibrium Calcite
precipitation under disequilibrium conditions can
be described by a kinetic Rayleigh process. Unlike
the enrichment of δ 13 C under equilibrium conditions,
this process is not influenced by temperature
only, but also by the drip interval. This is
due to the temporal development of bicarbonate
in the solution.
Results As a main result, the isotopic enrichment
of δ 13 C along the growth axis shows an increase
with increasing drip interval. Comparing all input
parameters, the drip interval seems to have
the highest variability during the growth period
of a stalagmite and might therefore be the main
influence on variations in growth and isotopic enrichment
of δ 13 C (see figure 6.1).
Outlook/Future work As a future task an
inversion of the box model is planned in order
to extract drip interval changes from stalagmite
records.
Funding This study is part of the daphne -
forschergruppe.
Main publications Mühlinghaus [2006]

162 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
6.1.2 A precisely dated climate record for the last 9 kyr from three high
alpine stalagmites, Spannagel Cave, Austria
Nicole Vollweiler (Participating scientists: Denis Scholz, Christian Mühlinghaus, Augusto Mangini,
Christoph Spötl (Innsbruck))
Abstract We used the δ 18 O time-series of three stalagmites from the high alpine Spannagel cave
(Austria) which grew in small distance from each other to construct a precisely U/Th-dated, continuous
δ 18 O curve for the last 9 kyr (COMNISPA).
δ 18 O [‰]
-9,0
-8,5
-8,0
-7,5
-7,0
-6,5
0
9 8 7 6 5 4 3 2 1 0
Age [kyr]
Figure 6.2: COMNISPA [Vollweiler et al. , 2006] in comparison with dated wood and peat samples
indicating glacier extensions smaller than 1985 AD [Joerin et al. , 2006]. The grey areas indicate the
uncertainty ranges for the composite parts of the curve
Background Stalagmites are ideally suited to
investigate short-term Holocene climate variability
because they can be precisely dated with Useries
methods and record variations of past temperature
and precipitation in their oxygen isotope
signals with high resolution. The Alps belong to
the regions where the Holocene climate variability
has been most intensively studied. Variations in
vegetation, glacier extension, timberline, tree-ring
width as well as periods of solifluction and pedogenesis
and lake and river history indicate major climate
oscillations. The Spannagel cave is located
around 2,500 m asl at the end of the Tux Valley
in Tyrol (Austria) close to the Hintertux glacier.
The speleothem record is not influenced by effects
of kinetic isotope fractionation due to the low temperatures
in the cave (presently between 1.8 ◦ and
2.0 ◦ C).
Methods and results The combined record
derived from the stalagmites SPA 12, SPA 128
and SPA 70 shows substantial variability within
the last 9 kyr (Fig.): The most pronounced and
long-lasting phase of low δ 18 O values occurs between
7.5 and 6.5 kyr and persists on slightly
higher values until 5.9 kyr. Further periods of low
δ 18 O values are between 3.8 and 3.6 kyr and during
the MWP between 1.2 and 0.7 kyr. Between
2.25 and 1.7 kyr, a time known as the Roman
Warm Period (RWP), some of the Alpine passes
were ice-free also in winter. COMNISPA shows
15
10
5
higher δ 18 O values during the RWP than during
the MWP and suggests a shorter duration of the
RWP than other archives. In contrast, periods
of high δ 18 O are visible between 7.9 and 7.5, 5.9
and 5.1, 3.5 and 3 kyr, and during the LIA between
600 and 150 yr. The period between 5.9
and 5.1 kyr has equivalence in many records from
various regions in both hemispheres corresponding
to global cooling. It also includes the time
of the Alpine Iceman at 5.3 kyr. The timing of
the climatic variations revealed by COMNISPA
agrees approximately with that shown by other
Alpine archives. For example, Joerin et al. [2006]
dated wood and peat samples which were released
by melting Swiss Alpine glaciers located between
Engadin and Valais. The Figure shows the age
distribution of their samples indicating glacier extensions
smaller than 1985 AD and, therefore, periods
when climatic conditions were different than
at this time. Both the δ 18 O maxima and minima
recorded in COMNISPA clearly have counterparts
in the glacier recession record.
Outlook/Future work We want to investigate
further Alpine stalagmites from the Spannagel
cave and from Obir Cave (South Austria) and
compare our records to other Holocene archives.
Funding DFG
Main publications Vollweiler et al. [2006]
Number of samples

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 163
6.1.3 Measurement of 231 Pa in deep-sea sediments via ICP-MS and AMS
Jörg Lippold
Abstract The measurement of the tracers 231 Pa and 230 Th allows high resolution studies for paleoproductivity
and ocean circulation on glacial to interglacial timescales. Using ICP-MS or AMS
higher precision will be obtaind compared to formerly applied α-spectroscopy for measuring the 231 Pa
/ 230 Th ratio of deep-sea sediments.
Figure 6.3: 230 Th norm. 10 Be-flux at ODP Sites 983 (North Atlantic) and 1089 (South Atlantic)
unaccounted for transport effects due to circulation or scavenging [Christl, Bernsdorff, Lippold]
Background 231 Pa and 230 Th are natural radionuclides,
which are continously produced in
seawater by in situ decay of their dissolved progenitors
234 U and 235 U. As a result, both are produced
at a constant rate with an initial 231 Pa and
230 Th activity ratio of 0.093. Variable 231 Pa and
230 Th ratios in sediments indicate that both radionuclides
follow different pathways of removal
from the water column. The flux of 230 Th to
the seafloor is nearly identical to its rate of production.
In contrast, the longer oceanic residence
time for dissolved 231 Pa due to lower particle reactivity
allows a large scale diffusive transport
over basin-wide distances prior to scavenging, resulting
in its preferential removal in high particle
flux regions. Particularly in the North Atlantic
region radioisotope signals may be significantly
influenced by changes in Ocean circulation. Up
to now, the 231 Pa and 230 Th -ratio is the best
kinematic proxy to quantify the strength of the
meridional overturning circulation. Thus, 231 Pa
and 230 Th -data, that provide the best estimate
of Ocean circulation in the past, can be used as
input for model calculations to quantify the transport
of other tracers (e.g. 10 Be, see figure above)
in the North Atlantic Ocean.
Methods and results The accurate and precise
determination of the very low 231 Pa content
in marine sediments requires the application of a
new analytical technique. ICP-MS is currently
the most suitable analytical tool for high precision
measurements of heavy isotope ratios. Therefore,
a cooperation with the Institute of Mineralogy
at the University of Frankfurt to develop the
appropriate analytical techniques for the determination
of Th/U, and Pa-isotope-ratios with Inductively
Coupled Plasma Mass Spectrometry (ICP-
MS) was initiated. Additionally an alternatively
method for measuring Pa with AMS (Accelerator
Mass Spectroscopy) at the ETH in Zürich has
been established, allowing to cross check results
and to highlight special aspects of the measurement.
Outlook/Future work In combination with
published 231 Pa and 230 Th -data from the North
Atlantic region, this records will help to greatly
improve our understanding of past Ocean circulation
in this region. Once established the 231 Pa
measurement method has been already applied to
further paleoclimate records, e.g. corals.
Funding DFG Schwerpunktprogramm 527 and
1158.
Main publications none yet

164 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
6.1.4 Ghost Resonance in Glacial Climate
Holger Braun
Abstract A new hypothesis was elaborated to explain the 1470-year cycle of abrupt climate changes
in the Last Glacial. This hypothesis was tested with two different types of models.
Figure 6.4: Illustration of the ghost resonance mechanism with a conceptual model. The forcing
(black, in arbitrary units) consists of two sinusoidal cycles with periods of 1470/7 (=210) and 1470/17
(about 86.5) years. Each time the forcing crosses a certain threshold function (green), the model
switches its state (negative values of the threshold function correspond to the ground state, positive
values to the excited state). The response of the system (i.e. the time evolution of the threshold
function) has a main spectral component of 1470 years, which is missing in the forcing.
Background Paleoclimatic records (ice cores,
deep sea sediments, speleothems) from the Last
Glacial show repeated large-scale (10-15 Kelvin)
warming events in the North Atlantic region, the
so-called Dansgaard-Oeschger (DO) events. In
the GISP2 ice core from Greenland, DO events
are often spaced by about 1470 years or multiples
thereof. This indicates that the events were
probably triggered by a regular external forcing.
But no such forcing with a pronounced 1470-year
spectral component is known.
Methods and results I elaborated a new hypothesis
to explain the 1470-year cyclicity of DO
events. According to this hypothesis, which I
tested with a climate model and a simple conceptual
model, the regularity of DO events is due to a
nonlinear resonance caused by a periodic external
forcing with a period of 1470 years, but without a
corresponding spectral component (i.e. with spectral
components corresponding only to harmonics
of a missing 1470-year fundamental frequency).
This resonance mechanism, which is known as
ghost resonance, can occur in excitable nonlinear
systems with a threshold. Since DO events probably
represent threshold-like switches between two
possible modes of deep water formation, the ghost
resonance mechanism is indeed plausible to explain
the events. The new hypothesis attributes
the glacial 1470-year cycle of DO events to solar
variability, since proxies of solar activity (i.e.
records of cosmogenic radionuclides) exhibit pronounced
spectral components near harmonics of
1470 years.
Outlook/Future work In the DFG project
Dansgaard-Oeschger events (DFG project number
MA821/33-1) I have started to investigate with a
climate model if past solar irradiance variations
could indeed have been strong enough to trigger
regular DO events in the Last Glacial.
Funding The work was funded by the Heidelberg
Academy of Sciences and by the DFG (DFG
project number MA821/33-1).
Main publications Braun et al. [2005]
Braun [2006]

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 165
6.1.5 Dating and interpretation of climate proxies for three Holocene stalagmites
from the South of Chile (Patagonia)
Daniel Schimpf (Participating scientists: C. Mühlinghaus, D. Scholz, A. Schröder-Ritzrau, A.
Mangini, R. Kilian (Trier), A. Kronz (Göttingen), C. Spötl (Innsbruck))
Abstract Three Holocene stalagmites (MA-1, MA-2 and MA-3) from the Marcelo-Arévalo cave,
which is located in the South of Chile (53 ◦ S) at the Pacific coast, were dated with the 230 Th/ 234 U
method and analysed with respect to their oxygen and carbon isotopes. Furthermore a Mg/Ca ratio
record for MA-1 was measured at high resolution. It is a proxy for precipitation and correlates very
well with the isotope data. We find that the West wind drift, which controls precipitation, is strongly
influenced by the El Nino Southern Oscillation.
δ 13 C (‰ VPDB)
0 1 2 3 4
-6
40 point smoothing 100*Mg/Ca
δ 13 C MA-1
-8
-10
-12
-14
-16
0 1 2 3 4
age (kyrs)
Figure 6.5: Correlation between δ 13 C data and the Mg/Ca ratio
Background For the first time stalagmites
from a cave of the southernmost Andes were analysed
at high resolution. The intensity of precipitation
at this location reflects the shifts of the
position of the West wind drift.
Methods and results The 230 Th/ 234 U dating
method was used to establish a depth-age model
for the three stalagmites (MA-1, MA-2 and MA-
3). The measurements were performed by a Thermal
Ionization Mass Spectrometer (TIMS). Furthermore
the Mg/Ca ratio was measured by Electron
Microprobe, this ratio is a proxy for precipitation.
Figure 6.5 shows a comparison between
the δ 13 C profile and Mg/Ca ratio of stalagmite
MA-1. The very good correlation between the two
records confirms that the δ 13 C record (and in the
same case the δ 18 O record) also depends on precipitation.
The comparison of the dated δ 13 C and
δ 18 O profiles with a record of the ENSO intensity,
derived from a sediment record off the coast of
Peru, reveals that ENSO strongly influenced the
1,0
0,9
0,8
0,7
0,6
0,5
0,4
0,3
0,2
0,1
100*Mg/Ca
intensity of precipitation, probably causing North-
South-shifts of the Southern Westerlies. An eruption
of volcano Mt. Burney (4.3 kyrs BP), which
occurred 100 km to the north-west of the MA cave,
resulted in a higher uranium content in the stalagmites
for the following 2 kyrs due to a leaching
effect caused by sulpherous ashes that covered the
soil above the cave.
Outlook/Future work ICP-MS data for all
three stalagmites have been measured, these trace
element data will be analysed. In addition a sediment
core of lake Tamar in the vicinity of the
MA cave has been taken and will be analysed.
The stable isotope profiles will be modelled by C.
Mühlinghaus.
Funding Stalagmite der Südanden, DFG
project
Main publication Schimpf [2005], Kilian et al.
[2006]

166 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
6.1.6 14 C in speleothems
Jens Fohlmeister (Participating scientists: Bernd Kromer, Denis Scholz, Renza Miorandi (Trento),
Silvia Frisia (Trento))
Abstract Using the absolute age of speleothem samples from Th/U-dating, we can determine their
14 C reservoir age. The 14 C reservoir age is controlled mainly by pCO2 in the unsaturated soil zone and
the dissolution system of the limestone. The main factors governing soil pCO2 are soil temperature and
precipitation. Hence, variations in the 14 C reservoir age may provide information on the variability
of these two climate variables.
d c f [% ]
1 7
1 6
1 5
1 4
1 3
1 2
1 1
1 0
9
8
5 0 0 0 4 0 0 0 3 0 0 0 2 0 0 0 1 0 0 0 0
c a l a g e [y B P ]
Figure 6.6: Dead carbon fraction (dcf) of stalagmite
ER-76. Dcf is increasing with time. Possible
causes are changes in the dissolution system or an
aging of soil organic matter.
Background Speleothems (carbonates formed
in caves) are excellent archives for studies of paleoclimate.
We use 14 C of stalagmites as a geochemical
tracer of climate-related processes in the unsaturated
soil zone. A useful tool for radiocarbon
interpretation is the dead carbon fraction (dcf).
It determines the percentual fraction of carbon in
a stalagmite, coming from the limestone or from
old organic matter of the soil above the cave.
In the soil the dcf is influenced by the soil respiration
rate (atmospheric 14 C content) and the
age spectrum of soil organic matter (depleted
by radioactive decay). By dissolution of the
limestone ( 14 C free) the dcf increases. The increase
depends on the open/closed dissolution ratio
[Hendy, 1971]. For the dcf we expect values
between 0 (for an open system) and 50% (for a
closed system).
Methods and results We choose two time approaches:
firstly we take a section of a stalagmite
in the Holocene and secondly we investigate the
present day situation by analysing drip water covering
an annual cycle.
We measured the 14 C content of the stalagmite
ER-76 of the Grotta di Ernesto (N-Italy), covering
a time span from 2.3 to 4.9 ky before present
and one sample at 180 y BP. For the second approach
we investigate the drip water of two sta-
a 1 4 C [p m C ]
1 0 2
1 0 1
1 0 0
9 9
9 8
9 7
9 6
9 5
9 4
E R -7 6 s lo w d rip ra te
E R -G 1 fa s t d rip ra te
N o v J a n M a r M a y J u l S e p
M o n th 0 5 /0 6
Figure 6.7: 14 C in drip water of two stalagtites
(ER-76, ER-G1). The 14 C activity imply different
processes, which are responsible for the annual
cycle.
lagtites (ER-76, ER-G1) of the same cave. Each
month we collect one sample of each source.
Sample preparation for Accelerator Mass
Spectrometry (AMS) 14 C dating was done in
the Heidelberg radiocarbon labaratory. The stalagmite
samples were drilled under a CO2 free
atmosphere in a glove box. By acidifying the
calcite powder and the drip water samples we obtain
CO2 which is converted to graphite (required
by the ion source) by the semi-automated AMStarget
preparation line. The AMS measurements
were done in Lund. The δ 18 O and the δ 13 C of the
drip water samples were measured in Heidelberg.
Figures 6.6 and 6.7 show first results of the
Holocene section and drip water, respectivly. The
results will be evaluated using additional information
from stable isotope information of both approaches
and from meteorological parameters for
the annual cycle.
Outlook/Future work We will follow another
annual cycle of drip water samples. It is planned
to study another Holocene section obtained from
a different cave.
Funding DFG Forschergruppe 668: ”Datierte
Speläotheme: Archive der Paläoumwelt”
Main publication Claussen et al. [2006]

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 167
6.1.7 Precise dating of D/O-Events on a stalagmite from Socorta Island
(Indian Ocean)
Isabela Hoschek
Abstract The stalagmite M1-2 from Socorta Island, which is located in the Indian Ocean in the
sphere of influence of the monsoon, is dated with more accuracy with the 230 T h/ 234 U method. The
intention is to determine a more exactly age for the Dansgaard-Oeschger-Events (D/O-events) 10, 11
and 12.
18 O
-2,0
-1,5
-1,0
-0,5
0,0
0,5
1,0
10 11 12
0 200 400 600 800 1000
Depth [mm]
Figure 6.8: Oxygen-isotope ratios of stalagmite M1-2.
Background Oxygen-isotope ratios of a stalagmite
from Socotra Island in the Indian Ocean provide
a record of changes in monsoon precipitation
and climate for the time period from 42 to 55
thousand years (kyr) before the present. The pattern
of precipitation bears a striking resemblance
to the oxygen-isotope record from Greenland ice
cores, with increased tropical precipitation associated
with warm periods in the high northern latitudes.
The chronology of the events found in the
record requires a reevaluation of previously published
time scales for climate events during this
period.
Methods and results The 230 T h/ 234 U dating
method is used to establish a depth-age model
for the stalagmite M1-2. The measurements are
performed with a Thermal Ionization Mass Spectrometer
(TIMS). The aim of the diploma thesis is
to accurately determine the age of (D/O-events)
10, 11 and 12 by analysis of several samples from
the same depth. This should allow (i) to calculate
a more reliable age uncertainty and (ii) to reduce
the analytical error. Figure 6.8 shows the oxygenisotope
record for stalagmite M1-2 [Burns et al. ,
2003].
Outlook/Future work Not available.
Funding Diploma thesis, therefore not applicable.

168 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
6.1.8 Trace element mapping of speleothems
Andrea Schröder-Ritzrau (Participating scientists: Yann Lahaye, Stefan Niggemann, Detlev Richter,
Dana Riechelmann, Denis Scholz , Christoph Spötl)
Abstract In recent years, numerous speleothem based proxy studies have advanced understanding of
annual to decadal scale climate variability. The Research Group DAPHNE is establishing a routine for
speleothem LA-ICP-MS measurements in cooperation with Prof. G. Brey, head of the Mineralogical
Institute, University of Frankfurt.
Figure 6.9: Ten point running mean Strontium content for two parallel profiles with a distance of 300
µm. The profiles show the same general trend. But, variations in small scale cyclicity are visible.
Background Trace elements (e.g. Mg, Ba, Sr,
P) cycles in speleothems may provide information
on past rainfall intensity [Johnson et al. , 2006;
Treble et al. , 2003, e.g.]. The DAPHNE group
is establishing a routine for speleothem analysis
with LA-ICP-MS in cooperation with the Mineralogical
Institute in Frankfurt, Germany.
Methods and results A 213nm Nd:YAG laser
ablation system (UP213 from NewWave) has been
coupled to an ICP-MS (Element 2 from Thermo
Electron Cooperation). Measurements are performed
versus the NIST 610 glass standard and
data are normalized to the calcium carbonate content
of the speleothem. This synthetic glass standard
has been used as an external standard of
reference. The calcium content of the sample has
also been monitored for the correction related to
matrix effect and for the calculation of the trace
element concentrations. First results of trace element
analysis on a Holocene stalagmite from the
Bunker Cave, Iserlohn, North West Germany, are
shown. The upper 28 mm of the stalagmite were
investigated and correspond to the last 2000 years.
Mg and Sr contents of the stalagmite are between
150 and 900ppm and 14 and 42 ppm, respectively.
Despite the relatively high noise in the data a general
trend to rising Sr values from 25 mm to 20mm
with maximum values between 18 to 12 mm is
depicted. In the upper 12mm of the stalagmite
Sr values are low with three visible excursion to
higher values. Generally, a superimposed, small
scale cyclicity is visible. However, the chronology
is still tentative. Hence, we are not yet able to calculate
growth rates and interpret cyclic variations
in trace element content.
Outlook/Future work The method will be
optimized. Trace element contents of additional
samples from Grotta di Ernesto, Italy, Bunker
Cave, Germany and other caves will be investigated.
The results will be interpreted in terms of
climate variability.
Funding FG DAPHNE (DFG)

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 169
6.1.9 U-series dating and paleoclimatic interpretation of the stable isotope
profile of stalagmite ER76 from Grotta di Ernesto, Italy
Denis Scholz (Participating scientists: Christoph Spötl (Innsbruck), Silvia Frisia (Trento), Andrea
Borsato (Trento), Jens Fohlmeister)
Abstract Stalagmite ER76 from Grotta di Ernesto, Italy, was precisely dated by TIMS Th/Udating.
The age-depth-model was constructed using a Bayesian approach to improve the dating
uncertainty and applying a mixed effect regression model. Furthermore, high-resolution stable oxygen
and carbon isotope profiles were determined.
A g e [k y r]
1 0
9
8
7
6
5
4
3
2
1
A g e -d e p th m o d e l (H e e g a a rd e t a l., 2 0 0 5 )
9 5 % c o n fid e n c e lim its
N e w U -s e rie s a g e s
U -s e rie s a g e s (M c D e rm o tt e t a l., 1 9 9 9 )
0
0 5 0 1 0 0 1 5 0 2 0 0 2 5 0 3 0 0 3 5 0 4 0 0
D is ta n c e fro m to p [m m ]
Figure 6.10: Final age-depth-model calculated for stalagmite ER76
Background Stalagmite ER76 from Grotta di
Ernesto, Italy, was precisely dated by TIMS
Th/U-dating. The age-depth-model was constructed
using a Bayesian approach to improve the
dating uncertainty and applying a mixed effect regression
model. Furthermore, high-resolution stable
oxygen and carbon isotope profiles were determined.
Methods and results Nine TIMS U-series
ages as well as high-resolution stable isotope profiles
on stalagmite ER76 from Grotta di Ernesto,
Italy, were determined. Due to its low 238 U (20-
40 ng/g) content which is typical for stalagmites
from Grotta di Ernesto, U-series dating of ER76
is rather difficult. Nevertheless, we were able to
determine a 230 Th/U-age of 2.27 0.08 kyr in the
youngest part, at 30 mm distance from top (dft).
However, due to the low U content, the error bars
of some data points overlap significantly. By application
of a Bayesian approach which takes into
account both the results of the U-series dating
and the stratigraphic sequence of the individual
samples the uncertainty of some data points could
be reduced substantially. We suggest to generally
apply this Bayesian approach when the individual
data point errors overlap. Overall, 13 data points,
nine measured in Heidelberg and four by McDermott
et al. [1999], were used to construct the final
age-depth relationship for ER76. The age model
and its uncertainty (see Fig. 6.10) was estimated
using a mixed-effect regression model [Heegaard
et al. , 2005]. Based on the new age model, ER76
exhibits a rather constant growth rate of approximately
0.05 mm/yr between 8.5 and 2 kyr. It
was actively growing when it was collected, and
Frisia et al. [2003] have shown that ER76 exhibits
annual laminae in the period between 1650
and 1995 AD. The thickness of these annual laminae
lies between 0.02 and 0.1 mm. In combination
with the new age model obtained by U-series dating
this shows that there must be a substantial
hiatus between 2 and 0.5 kyr in ER76. Oxygen
and carbon stable isotope profiles were measured
at the University of Innsbruck at a resolution of
0.1 mm between 0 and 8 mm dft and 0.25 mm
below 8 mm dft.
Outlook/Future work An earlier study [Mc-
Dermott et al. , 1999] revealed that ER76 recorded
several Holocene warm/dry and cold/wet phases,
respectively. Because the resolution in that study
was approximately 2 mm, the new profiles have
a ten times higher resolution which should enable
to detect even rapid climate events.
Funding DFG Forschergruppe 668: ”Datierte
Speläotheme: Archive der Paläoumwelt”
Main publication Vollweiler et al. [2006],
Scholz & Mangini [2006], Scholz & Mangini [accepted
for publication], Mangini et al. [accepted
for publication]

170 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
6.1.10 Kinetic Fractionation of Stable Isotopes in Speletothems - Laboratory
Experiments
Daniela Polag (Participating scientists: E. Wiedner, D. Scholz, R. März, A. Schröder-Ritzrau, A.
Mangini, C. Spötl, M. Segl)
Abstract Many speleothems show evidence for calcite precipitation under disequilibrium conditions.
To improve the understanding of these kinetic processes, laboratory experiments were carried out to
study the fractionation of stable oxygen and carbon isotopes during the precipitation of calcite.
Figure 6.11: Picture of the experiment setup that was used to precipitate synthetic carbonates under
controlled conditions in the laboratory.
Background To deduce paleoclimatic information
from calcite which is precipitated under nonequilibrium-conditions
it is important to understand
the influence of kinetic fractionation processes
for example in what extent different parameters
like drip rate and temperature affecting the
slope of ∆(δ 18 O/δ 13 C). In this context laboratory
experiments with controlled parameters like
solution composition, temperature and drip rate
should help to improve the understanding of kinetic
fractionation of oxygen and carbon stable
isotopes with reference to natural speleothems.
Methods and results The laboratory experiments
are conducted in a refrigerator under 100%
relative humidity and for the present in a pure
nitrogen atmosphere. A mixture of two solutions
(CaCl2 and NaHCO3) flows on a glass fiber
stripe along a 32 ◦ dipping rod with a length of 50
cm, representing the water film flowing alongside
a stalagmite. The humidified nitrogen gas flushes
the rod and carry along the fast degassing CO2
from the solution leading to a Rayleigh fractionation
within the isotope compound.
First results indicate that the isotopic enrichment
of δ 13 C and δ 18 O is significantly related to the
solution flow speed which means that the isotopic
enrichment increases with a larger drip interval.
Another objective of the experiments had been
the investigation on the effects of different
magnesium/calcium-ratios. The magnesium distribution
coefficient is an important parameter
in paleoclimate investigation because of the temperature
dependence of the magnesium build up.
First results within this context show that the
measured magnesium partitioning coefficients fit
in the range of published values [Gascoyne, 1983];
[Burton & Walter, 1999].
Outlook/Future work For future work the influence
of different experimental parameters on
the enrichment of δ 13 C and δ 18 O will be tested.
Experiments will be conducted under lower temperatures
and slower drip rates. Besides, the fiber
glass as a substrate for the precipitating calcite
will be investigated and compared with other surfaces
acting as a seed for calcite crystallisation.
Funding DFG (DAPHNE Forschergruppe)
Main publications Results from former experimental
work (Elke Wiedner) are lately submitted
to Quarternary International (Elsevier)

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 171
6.1.11 231 Pa/ 235 U-Dating of fossil corals with AMS
Kerstin Bauer (Participating scientists: Denis Scholz, Jörg Lippold)
Abstract The ages of fossil reef corals from Aqaba, Jordan, and Barbados, West Indies, are determined
by uranium-series dating. The samples are prepared with ion exchange chemistry and analysed
by thermal ionisation mass spectrometer (TIMS) for 231 Th, 234 U, and 238 U and by accelerator mass
spectometry (AMS) for 231 Pa and 235 U. The ages obtained by both methods are compared for consistency.
If they differ, the coral is assumed to show open-system-behaviour.
� ��� ����� ��� ��
1 ,2
1 ,0
0 ,8
0 ,6
0 ,4
0 ,2
δ ��� � ������� ��������
0 ,0
0 ,0 0 ,2 0 ,4 0 ,6 0 ,8 1 ,0
� ��� ����� ��� ��
δ ��� � ������� ��������
1 ,2 0
1 ,1 5
1 ,1 0
1 ,0 5
1 ,0 0
0 ,0 0 ,2 0 ,4 0 ,6 0 ,8 1 ,0 1 ,2
� ��� ����� ��� ��
Figure 6.12: Concordia diagrams for the U-Th-Pa system. The straight lines show the timely development
of the ( 230 Th/ 238 U), ( 234 U/ 238 U), and ( 231 Pa/ 235 U) activity ratios with an initial ( 234 U/ 238 U)
activity ratio of 1.1496 (modern seawater). The red circle indicates a coral which has behaved as a
closed system for 100 kyr. The dashed lines indicate the 100-kyr-closed-system isochrons.
Background The main goal of U-series dating
of fossil reef corals is to reconstruct past sea level
changes during the last 300,000 years. Some coral
species only inhabit the upper five metres below
the sea surface. If their age and their location relative
to the current sea level are known and if a
correction for the uplift or subsidence of the land
mass can be applied, the change of the sea level
can be calculated. It is an established procedure
to determine the age of carbonates by measuring
the ratio between 238 U and its decay series daughters
230 Th and 234 U. This has been done with the
TIMS of the group for several years. Still, the
age of a coral determined by this method can be
inaccurate due to open system behaviour and geochemical
processes of isotope mobilization which
alter the activity ratios which are used for dating.
Numerous criteria to identify diagenetically
altered corals can be applied. In addition, several
so-called open-system models have been developed
to correct the diagenetic changes and calculate
the true coral age [Scholz, 2005]. The subject
of this diploma thesis is another access to validate
the accuracy of fossil coral ages: the decay
� ��� ���� ��� ��
of 235 U to 231 Pa, which provides a second ”clock”.
Methods and results The 231 Pa/ 235 U dating
method can be applied for the last 250,000 years
and in this timeframe it can be compared with
the results of 238 U/ 230 Th method. If the coral behaved
as a closed system, both ages should be concordant
and different ages of a coral system should
plot on a concordia line (see Fig. 6.12). This technique
is planned to be tested on corals collected at
Barbados (West Indies) and Aqaba (Jordan, Red
Sea). Thereby the dating with 231 Pa is associated
with some difficulties as there must be a different
chemical sample preparation. In addition, there
is no long-living isotope which can be used as a
spike. The only possibility is to use 233 Pa (t 1/2
= 26,97 d) which must be separated shortly before
the measurement from a Np mother. Furthermore,
the abundance of Pa is lower than that of
Th and is not measured at the local TIMS, but at
an AMS at the ETH in Zuerich, Switzerland.
Funding Diploma thesis, therefore not applicable.

172 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
6.1.12 Reconstruction of the geomagnetic field strength over the past
300.000 years derived from 10 Be data of deep sea sediments from
the North and South Atlantic Ocean
Frank Bernsdorff
Abstract In this project we use the anti correlation between the 10 Be production in the earths
stratosphere via galactic cosmic rays and the strength of the geomagnetic field to determine its variation
over a time period of 300.000 years. Hence two deep sea sediment cores (ODP) from the Atlantic
Ocean, which act as 10 Be archives are investigated.
Figure 6.13: Schematic pathway of the production and deposition of cosmogenic 10 Be
Background The cosmogenic nuclide 10 Be is
mainly produced in the lower stratosphere by
inter-action of galactic cosmic rays with oxygen
and nitrogen atoms, and its production is
known to be strongly anti-correlated with the
solar- and/or geomagnetic field strength. After a
short atmospheric residence time of about 1 year
10 Be is removed from this part of the atmosphere
and deposited onto land, ice sheets and (mainly)
the ocean surface. Therefore it should be possible
to extract a record of geomagnetic paleointensity
(GPI) from depositional profiles of these radionuclides
in marine, terrestrial and ice core archives.
In this study we are investigating two deep sea
sediment cores from the North and Northwest Atlantic
Ocean (ODP-Site 983 and ODP-Site 1063)
for highly resolved 10 Be profiles. The application
of a special correction procedure (involving uranium
and thorium measurements) is indispensable
to quantify the transport of 10 Be in the ocean, so
that the global 10 Be-production can be extracted
from marine records. Based on these profiles, a
marine 10 Be stratigraphy will be developed that
can be matched with 10 Be records from Greenland
(GRIP, GISP II) and Antarctic (EPICA) ice
cores.
Methods and results In addition to the above
specified goals a new analytical technique had to
be developed and applied for the uranium and
thorium measurements to get more precise data
sets in shorter times (compared to Alpha spec-
trometry). This was implemented by the application
of an ICP-SF-MC-MS (Inductively Coupled
Plasma Sector Field Multi Collector Mass Spectrometer)
for the uranium and thorium measurements.
To assure consistent data sets different
standard materials (e.g. certified standard solutions
of thorium and uranium isotopes as well as
deep sea sediment samples of known isotopic composition)
were tested intensively. After these initial
experiments we could assure the quality of
the following measurements concerning the deep
sea sediment cores: ODP 983 and 1063. Those
data sets will be processed and evaluated within
the next month.
Nevertheless, first results of the 230 Th xs(0) corrected
data sets of 10 Be are showing already that
we are able to reconstruct at least the LaChampand
Jamaica Event.
Outlook/Future work Outlook/Future work
According to the goals of this project the future
work will mainly comprise 10 Be measurements of
the deep sea sediments from ODP site 983 and
1063, its normalisation to 230 Th xs(0) and comparison
to the data set of ODP site 1089 (South
Atlantik).
Funding DFG Schwerpunktprogramm: Integrated
Ocean Drilling Program/Ocean Drilling
Program (IODP/ODP); (SPP 527)
Main publication Muscheler et. al [2005]

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 173
References
Beer, J., Mende, W., & Stellmacher, R. 2000. The role of the sun in climate forcing. Quaternary
Science Reviews, 19, 403–415.
Björck, S., Rittenour, T., Rosén, P., Franca, Z., Mller, P., Snowball, I., Wastegard, S., O., Bennike,
& B., Kromer. 2006. A Holocene lacustrine record in the central North Atlantic: proxies for volcanic
activity, short-term NAO mode variability, and long-term precipitation changes. Quarternary
Science Reviews, 25, 9–32.
Bond, Gerard, Kromer, Bernd, Beer, Juerg, Muscheler, Raimund, Evans, Mike, Showers, William,
Hoffmann, Sharon, Lotti-Bond, Rusty, Hajdas, Irka, & Bonani, Georges. 2001. Persistent Solar
Influence on North Atlantic Surface Circulation During the Holocene. Science, 294(2130-2136).
Braun, H. 2006. A new hypothesis for the 1470-year cycle of abrupt warming events in the last ice-age.
Ph.D. thesis, Ruprecht-Karls-University, Heidelberg.
Braun, H., Christl, M., Rahmstorf, S., Ganopolski, A., Mangini, A., Kubatzki, C., Roth, K., &
Kromer, B. 2005. Possible solar origin of the glacial 1,470-year glacial climate cycle demonstrated
in a coupled mode. Nature, 438, 208 – 211.
Burns, S., Fleitmann, D., Matter, A., Kramers, J., & Al-Subbary, A. 2003. Indian Ocean Climate and
an Absolute Chronology over Dansgaard/Oeschger Events 9 to 13. Science, 301, 1365–1367.
Burns, S.J., Fleitmann, D., Mudelsee, M., Neff, U., Matter, A., & Mangini, A. 2002. A 780-year
annually resolved record of Indian Ocean monsoon precipitation from a speleothem from south
Oman. Journal of Geophysical Research, 107(D20), doi:10.1029/2001JD001281.
Burton, E.A., & Walter, L.M. 1999. The effects of PCO2 and temperature on magnesium incorporation
in calcite on seawater and MgCl2-CaCl2 solutions. Geochimica et Cosmochimica Acta, 55, 777 –
785.
Claussen, M., Fohlmeister, J., Ganopolski, A., & Brovkin, V. 2006. Vegetation Dynamics Amplifies
Precessional Forcing. Geophys. Res. Lett., 33.
Eddy, J. 1976. The mounder minimum. Science, 192, 1189–1202.
Eitel, B., Hecht, S., Mchtle, B., Schukraft, G., Kadereit, A., Wagner, G. A., Kromer, B., Unkel, I., &
Reindel, M. 2005. Geoarchaeological evidence from desert loess in the Nazca/Palpa region, Southern
Peru: Palaeoenvironmental changes and their impact on Pre-Columbian cultures. Archaeometry,
47(1), 137–158.
Fleitmann, D., Burns, S.J., Mudelsee, M., Neff, U., Kramers, J., Mangini, A., & Matter, A. 2003.
Holocene Forcing of the Indian Monsoon Recorded in a Stalagmite from Southern Oman. Science,
300(5626), 1737–1739.
Frank, N., Kober, B., & Mangini, A. 2006. Carbonate precipitation, U-series dating, and U.isotopic
variations in a Holocene Travertine Platform at Bad Langensalza- Thuringian Basin. Quaternaire,
17(4), 321–330.
Friedrich, Michael, Remmele, Sabine, Kromer, Bernd, Hofmann, Jutta, Spurk, Marco, Kaiser,
Klaus Felix, Orcel, Christian, & Kppers, Manfred. 2004. The 12,460-Year Hohenheim Oak and
Pine Tree-Ring Chronology from Central Europe - a Unique Annual Record for Radiocarbon Calibration
and Paleoenvironment Reconstructions. Radiocarbon, 46(3), 1111–1122.
Friedrich, W. L., Kromer, B., Friedrich, M., Heinemeier, J., Pfeiffer, T., & S., Talamo. 2006. Santorini
Eruption Radiocarbon Dated to 1627-1600 B.C. Science, 312, 548.
Frisia, S., Borsato, A., Preto, N., & McDermott, F. 2003. Late Holocene Annual Growth in Three
Alpine Stalagmites Records the Influence of Solar Activity and the North Atlantic Oscillation on
Winter Climate. EPSL, 216, 411 – 424.
Frisia, S., Borsato, A., Mangini, A., Sptl, C., Madonia, G., & Sauro, U. 2006. Holocene climate
variability in Sicily from a discontinuous stalagmite record and the Mesolithic to Neolithic transition.
Quaternary Research, 66, 388–400.

174 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
Gascoyne, M. 1983. Trace element partition coefficients in the calcite-water system and their paleoclimatic
significance in cave studies. Journal of Hydrology, 61, 213 – 222.
Heegaard, E., Birks, H. J. B., & Telford, R. J. 2005. Relationships between calibrated ages and depth
in stratigraphical sequences: an estimation procedure by mixed-effect regression. The Holocene,
15(4), 612 – 618.
Hendy, C.H. 1971. The Isotopic Geochemistry of Speleothems – I. The Calculation of the Effects of
Different Modes of Formation on the Isotopic Composition of Speleothems and Their Applicability
as Palaeoclimatic Indicators. Geochimica et Cosmochimica Acta, 35, 801 – 824.
Hodell, D.A., Brenner, M., Curtis, J.H., & Guilderson, T. 2001. Solar Forcing of Drought Frequency
in the Maya Lowlands. Science, 292, 1367–1370.
Hughen, Konrad A, Baillie, Mike G L, Bard, Edouard, Beck, J Warren, Bertrand, Chanda J H,
Blackwell, Paul G, Buck, Caitlin E, Burr, George S, Cutler, Kirsten B, Damon, Paul E, Edwards,
Richard L, Fairbanks, Richard G, Friedrich, Michael, Guilderson, Thomas P, Kromer, Bernd, Mc-
Cormac, Gerry, Manning, Sturt, Ramsey, Christopher Bronk, Reimer, Paula J, Reimer, Ron W,
Remmele, Sabine, Southon, John R, Stuiver, Minze, Talamo, Sahra, Taylor, F W, Plicht, Johannes
van der, & Weyhenmeyer, Constanze E. 2004. Marine04 Marine Radiocarbon Age Calibration, 0-26
Cal Kyr BP. Radiocarbon, 46(3), 1059–1086.
Joerin, U.E., Stocker, T.F., & Schlüchter, C. 2006. Multicentury glacier fluctuations in the Swiss Alps
during the Holocene. The Holocene, 16, 697 – 704.
Johnson, K.R., Hu, C., Belshaw, N.S., & Henderson, G.M. 2006. Seasonal trace-element and stableisotope
variations in a Chinese speleothem The potential for high-resolution paleomonsoon reconstruction.
Earth and Planetary Science Letters, 244, 394 – 407.
Kilian, R., Biester, H., Behrmann, J., Baeza, O., Fesq-Martin, M., Hohner, M., Schimpf, D., Friedmann,
A., & Mangini, A. 2006. Millennium-scale volcanic impact on a superhumid and pristine
ecosystem. Geology, 34(8), 609–612.
Kromer, B., Korfmann, M., & Jablonka, P. 2002. Heidelberg radiocarbon dates for Troia I to VIII
and Kumtepe. Pages 43–54 of: Wagner, G. (ed), Troia and the Troad. Heidelberg: Springer.
Kromer, B., Friedrich, M., Hughen, K.A., Kaiser, F., Remmele, S., Schaub, M., & Talamo, S. 2004.
Late Glacial 14C ages from a floating 1382-ring pine chronology. Radiocarbon, 46(3), 1203–1209.
Labitzke, K., & Loon, H. 1992. Association between the 11-Year Solar Cycle and the Atmosphere.
Part V: Summer. Journal of Climate, 5, 240–251.
Latuske, N. 2006. Solare Variabilitt und Klimaänderungen auf einer Zeitskala von einigen Dekaden
bis Jahrhunderten im Holozän. Ph.D. thesis, Ruprecht-Karls-University, Heidelberg.
Levin, Ingeborg, & Kromer, Bernd. 2004. The Tropospheric 14 CO2 level in Mid-Latitudes of the
Northern Hemisphere (1959-2003). Radiocarbon, 46(3), 1261–1272.
Mangini, A., Verdes, P., Sptl, C., Scholz, D., Vollweiler, N., & Kromer, B. accepted for publication.
Persistent influence of the North Atlantic hydrography on Central European winter temperature
during the last 9,000 years. Geophysical Research Letters.
Manning, Sturt W., Kromer, Bernd, Kuniholm, Peter Ian, & Newton, M. W. 2001. Anatolian treerings
and a new chronology for the east Mediterranean Bronze-Iron Ages. Science, 294(2532-2535).
Manning, Sturt W., Kromer, B., Kuniholm, P.I., & Newton, M. W. 2003. Confirmation of nearabsolute
dating of east Mediterranean Bronze-Iron Dendrochronology. Antiquity, 77(295).
Manning, S.W., Ramsey, C.B., Kutschera, W., Higham, T., Kromer, B., Steier, P., & E.M., Wild.
2006. Chronology for the Aegean Late Bronze Age 1700-1400 B.C. Science, 312, 565–569.
McDermott, F., Frisia, S., Huang, Y., Longinelli, A., Spiro, B., Heaton, T. H. E., Hawkesworth, C. J.,
Borsato, A., Keppens, E., Fairchild, I. J., van der Borg, K., Verheyden, S., & Selmo, E. M. 1999.
Holocene climate variability in Europe: Evidence from δ 18 O, textural and extension-rate variations
in three speleothems. Quaternary Science Reviews, 18, 1021 – 1038.

6.1. FORSCHUNGSSTELLE “RADIOMETRIE” 175
Mühlinghaus, C. 2006. Modellierung paläoklimatischer Parameter anhand Wachstum und Isotopiekorrelationen
von Stalagmiten. Diploma thesis, Heidelberg University.
Muscheler et. al. 2005. Geomagnetic field intensity during the last 60,000 years based on 10 Be and
36 Cl from the Summit ice cores and 14 C. Quaternary Science Reviews.
Neff, U., Burns, S.J., Mangini, A., Mudelsee, M., Fleitmann, D., & Matter, A. 2001. Strong coherence
between solar variability and the monsoon. Nature, 411, 290–293.
Ney, E.P. 1959. Cosmic radiation and weather. Nature, 183, 451.
Niggemann, S., Mangini, A., Mudelsee, M., Richter, D.K., & Wurth, G. 2003. Sub-Milankovitch
climatic cycles in Holocene stalagmites from Sauerland, Germany. Earth and Planetary Science
Letters, 6844, 1–9.
Reimer, Paula J, Baillie, Mike G L, Bard, Edouard, Bayliss, Alex, Beck, J Warren, Bertrand, Chanda
J H, Blackwell, Paul G, Buck, Caitlin E, Burr, George S, Cutler, Kirsten B, Damon, Paul E,
Edwards, R Lawrence, Fairbanks, Richard G, Friedrich, Michael, Guilderson, Thomas P, Hogg,
Alan G, Hughen, Konrad A, Kromer, Bernd, McCormac, Gerry, Manning, Sturt, Ramsey, Christopher
Bronk, Reimer, Ron W, Remmele, Sabine, Southon, John R, Stuiver, Minze, Talamo, Sahra,
Taylor, F W, Plicht, Johannes van der, & Weyhenmeyer, Constanze E. 2004. INTCAL04 terrestrial
radiocarbon age calibration, 0-26 cal kyr BP. Radiocarbon, 46(3), 1029–1058.
Schaub, Matthias, Kaiser, Klaus F., Kromer, Bernd, & Talamo, Sahra. 2005. Extension of the Swiss
Lateglacial tree-ring chronologies. Dendrochronologia, doi:10.1016.
Schimpf, D. 2005. Datierung und Interpretation der Kohlenstoff- und Sauerstoffisotopie zweier
holozäner Stalagmiten aus dem Süden Chiles (Patagonien). M.Phil. thesis, Ruprecht-Karls-
University, Heidelberg.
Scholz, D. 2005. U-series dating of diagenetically altered fossil reef corals and the application for sea
level reconstructions. Ph.D. thesis, Ruprecht-Karls-University, Heidelberg.
Scholz, D., & Mangini, A. 2006. U-redistribution in fossil reef corals from Barbados, West Indies, and
sea level reconstruction for MIS 6.5. The climate of past Interglacials. in press.
Scholz, D., & Mangini, A. accepted for publication. The uncertainty of coral isochron ages. Quaternary
Geochronology.
Solanki, S. K., Usoskin, I. G., Kromer, B., Schssler, M., & Beer, J. 2004. Unusual activity of the Sun
during recent decades compared to the previous 11,000 years. Nature, 431, 1084–1087.
Soon, W.H., Posmentier, E.S., & Baliunas, S.L. 2000. Climate hypersensitivity to solar forcing?
Annales Geophysicae, 18, 583–588.
Spötl, C., & Mangini, A. 2005. Altersbestimmungen an Griffner Tropfsteinen. Page 336pp of: Komposch,
C., & Wieser, C. (eds), Schlossberg Griffen: Klagenfurt. Verlag des Naturwissenschaftlichen
Vereins fr Kärnten.
Spötl, C., & Mangini, A. 2006. U/Th age constraints on the absence of ice in the central Inn Valley
(eastern Alps, Austria) during Marine Isotope Stages 5c to 5a. Quaternary Research, 66, 167–175.
Spötl, C., Mangini, A., & Richards, D.A. 2006. Chronology and paleoenvironment of Marine Isotope
Stage 3 from two high-elevation speleothems, Austrian Alps. Quaternary Science Reviews, 25,
1127–1136.
Svensmark, H., & Friis Christensen, E. 1997. Variation of cosmic ray flux and global cloud coverage-a
missing link in solar-climate relationships. J. Atmos. Terr. Phys, 59, 1225–1232.
Treble, P., Shelley, J.M.G., & Chappell, J. 2003. Comparison of high resolution sub-annual records of
trace elements in a modern (1911-1992) speleothem with instrumental climate data from southwest
Australia. Earth and Planetary Science Letters, 216, 141 – 153.
Unkel, I. 2006. AMS- 14 C-Analysen zur Rekonstruktion der Landschafts- und Kulturgeschichte in der
Region Palpa (S-Peru). Ph.D. thesis, Ruprecht-Karls-University, Heidelberg.

176 CHAPTER 6. FORSCHUNGSSTELLE “RADIOMETRIE”
Usoskin, I.G., Solanki, S.K., Kovaltsov, G.A., Beer, J., & Kromer, B. 2006. Solar proton events in
cosmogenic isotope data. Geophys. Res. Lett., 33.
Usoskin, Ilya G, & Kromer, Bernd. 2005. Reconstruction of the 14 C Production Rate from Measured
Relative Abundance. Radiocarbon, 47(1), 31–37.
Vollweiler, N. 2005. Stalagmiten aus der Spannagel-Höhle bei Hintertux (Tirol, Österreich) - Archive
für das Klima der Alpen im Holozän. Diploma thesis, Heidelberg University.
Vollweiler, N., Scholz, D., Mühlinghaus, C., Mangini, A., & Spötl, C. 2006. A precisely dated climate
record for the last 9 kyr from three high alpine stalagmites, Spannagel Cave, Austria. Geophysical
Research Letters, 33, L20703.

Bibliography
177

7.1. PEER REVIEWED PUBLICATIONS 179
Peer Reviewed Publications
Aeschbach-Hertig, W. 2006. Rebuttal of ”‘On global forces of nature driving the Earth’s climate. Are
humans involved?”’. Env. Geol. DOI 10.1007/s00254-006-0519-3.
Aeschbach-Hertig, W., Holzner, C. P., Hofer, M., Simona, M., Barbieri, A., & Kipfer, R. 2007. A
time series of environmental tracer data from deep meromictic Lake Lugano, Switzerland. Limnol.
Oceanogr., 52, 257 – 273.
Aiuppa, A., Franco, A., von Glasow, R., Allen, A. G., D’Alessandro, W., Mather, T. A., Pyle, D. M.,
& Valenza, M. 2006. The tropospheric processing of acidic gases and hydrogen sulphide in volcanic
gas plumes as inferred from field and model investigations. Atmos. Chem. Phys. Discuss., 6, 11653
– 11680.
Allen, G., Mather, T.A., McGonigle, A.J.S., Aiuppa, A., Delmelle, P., Davison, B., Bobrowski,
N., Oppenheimer, C., Pyle, D.M., & Inguaggiato, S. 2006. Sources, size distribution and downwind
grounding of aerosols from Mt. Etna. Journal of Geophysical Research, 111(D10302).
doi:10.1029/2005JD006015.
Beirle, S., Spichtinger, N., Stohl, A., Cummins, K. L., Turner, T., Boccippio, D., Cooper, O. R., Wenig,
M., Grzegorski, M., Platt, U., & Wagner, T. 2006. ESTIMATING THE NOx PRODUCED BY
LIGHTNING FROM GOME AND NLDN DATA: A CASE STUDY IN THE GULF OF MEXICO.
Atmos. Chem. Phys., 6, 10751089.
Bergamaschi, P., Frankenberg, C., Meirink, J. F., Kroll, M., Dentener, F., Wagner, T., Platt, U., Kaplan,
J. O., Körner, S., Heimann, M., Dlugokencky, E. J., & Goede, A. 2006. SATELLITE CHAR-
TOGRAPHY OF ATMOSPHERIC METHANE FROM SCIAMACHY ONBOARD ENVISAT: (II)
EVALUATION BASED ON INVERSE MODEL SIMULATIONS. J. Geophys. Res., accepted.
Bigler, M., Rthlisberger, R., Lambert, F., Stocker, T.F., & Wagenbach, D. 2006. Aerosol deposited
in East Antarctica over the last glacial cycle: Detailed apportionment of continental and sea-salt
contributions. Journal of Geophysical Research, 111, (8)(D08205).
Björck, S., Rittenour, T., Rosén, P., Franca, Z., Mller, P., Snowball, I., Wastegard, S., O., Bennike,
& B., Kromer. 2006. A Holocene lacustrine record in the central North Atlantic: proxies for volcanic
activity, short-term NAO mode variability, and long-term precipitation changes. Quarternary
Science Reviews, 25, 9–32.
Bobrowski, N., von Glasow, R., Aiuppa, A., Inguaggiato, S., Louban, I., Ibrahim, O. W., & Platt, U.
2006a. Halogen Chemistry in Volcanic Plumes. J. Geophys. Res., in press.
Bobrowski, N., Hönninger, G., Lohberger, F., & Platt, U. 2006b. I-DOAS: A new monitoring technique
to study the 2D distribution of volcanic gas emissions. Journal of Volcanology and Geothermal
Research, 150(4), 329–338.
Bobrowski, N., Glasow, R.v., Aiuppa, A., Inguaggiato, S., Louban, I., Ibrahim, O.W., & Platt,
U. 2006c. Reactive Halogen Chemistry in Volcanic Plumes. Journal of Geophysical Research.
accepted,2006JD007206.
Braun, H., Christl, M., Rahmstorf, S., Ganopolski, A., Mangini, A., Kubatzki, C., Roth, K., &
Kromer, B. 2005. Possible solar origin of the glacial 1,470-year glacial climate cycle demonstrated
in a coupled mode. Nature, 438, 208 – 211.
Bruns, M., Buehler, S.A., Burrows, J.P., Richter, A., Rozanov, A., Wang, P., Heue, K.-P., Platt, U.,
Pundt, I., & Wagner, T. 2006a. NO2 Profile retrieval using airborne multi axis UV-visible skylight
absorption measurements over central Europe. Atmospheric Chemistry and Physics, 6, 3049–3058.
Bruns, M., Buehler, S. A., Burrows, J. P., Richter, A., Rozanov, A., Wang, P., Heue, K.-P., Platt, U.,
Pundt, I., & Wagner, T. 2006b. NO2 PROFILE RETRIEVAL USING AIRBORNE MULTI AXIS
UV-VISIBLE SKYLIGHT ABSORPTION MEASUREMENTS OVER CENTRAL EUROPE. Atmos.
Chem. Phys., 6, 3049–3058.
Butz, A., Bösch, H., Camy-Peyret, C., Chipperfield, M. P., Dorf, M., G., Dufour, Grunow, K., Jeseck,
P., Kühl, S., Payan, S., Pepin, I., Pukite, J., Rozanov, A., von Savigny, C., Sioris, C., Weidner,
F., & Pfeilsticker, K. 2006a. Inter-comparison of stratospheric O3 and NO2 abundances retrieved
from balloon borne direct sun observations and Envisat/SCIAMACHY limb measurements. Atmos.
Chem. Phys., 6, 1293–1314.

180 CHAPTER 7. BIBLIOGRAPHY
Butz, A., Bösch, H., Camy-Peyret, C., Chipperfield, M., Dorf, M., Dufour, G., Grunow, K., Jeseck,
P., Kühl, S., Payan, S., Pepin, I., Pukite, J., Rozanov, A., von Savigny, C., Sioris, C., Wagner, T.,
Weidner, F., & Pfeilsticker, K. 2006b. INTER-COMPARISON OF STRATOSPHERIC O3 AND
NO2 ABUNDANCES RETRIEVED FROM BALLOON BORNE DIRECT SUN OBSERVATIONS
AND ENVISAT/SCIAMACHY LIMB MEASUREMENTS. Atmos. Chem. Phys., 6, 1293–1314.
Claussen, M., Fohlmeister, J., Ganopolski, A., & Brovkin, V. 2006. Vegetation Dynamics Amplifies
Precessional Forcing. Geophys. Res. Lett., 33.
Dils, B., De Maziere, M., Blumenstock, T., Buchwitz, M., de Beek, R., Demoulin, P., Duchatelet, P.,
Fast, H., Frankenberg, C., Gloudemans, A., Griffith, D., Jones, N., Kerzenmacher, T., Kramer, I.,
Mahieu, E., Mellqvist, J., Mittermeier, R. L., Notholt, J., Rinsland, C. P., Schrijver, H., Smale,
D., Strandberg, A., Straume, A. G., Stremme, W., Strong, K., Sussmann, R., Taylor, J., van den
Broek, M., Wagner, T., Warneke, T., Wiacek, A., & Wood, S. 2006. COMPARISONS BETWEEN
SCIAMACHY AND GROUND-BASED FTIR DATA FOR TOTAL COLUMNS OF CO, CH4, CO2
AND N2O. Atmos. Chem. Phys., 6, 1953–1976.
Dorf, M., Bösch, H., Butz, A., Camy-Peyret, C., Chipperfield, M. P., Engel, A., Goutail, F., Grunow,
K., Hendrick, F., Hrechanyy, S., Naujokat, B., Pommereau, J.-P., Van Roozendael, M., Sioris, C.,
Stroh, F., Weidner, F., & Pfeilsticker, K. 2006a. Balloon-borne stratospheric BrO measurements:
Comparison with Envisat/SCIAMACHY BrO limb profiles. Atmos. Chem. Phys., 6, 2483–2501.
Dorf, M., Butler, J. H., Butz, A., Camy-Peyret, C., Chipperfield, M. P., Kritten, L., Montzka, S. A.,
Simmes, B., Weidner, F., & Pfeilsticker, K. 2006b. Long-term observations of stratospheric bromine
reveal slow down in growth. Geophys. Res. Lett., 33, L24803. doi:10.1029/2006GL027714.
Edmunds, W. M., Ma, J.Z., Aeschbach-Hertig, W., Kipfer, R., & Darbyshire, D.P.F. 2006. Groundwater
recharge history and hydrogeochemical evolution in the Minqin Basin, North West China.
Appl. Geochem., 21, 2148–2170.
Engel, A., Möbius, T., Haase, H.-P., Bönisch, H., Wetter, T., Schmidt, U., Levin, I., Reddmann, T.,
Oelhaf, H., Wetzel, G., Grunow, K., Huret, N., & Pirre, M. 2006. Observation of mesospheric air
inside the arctic stratospheric polar vortex in early 2006. Atmos. Chem. Phys., 6, 267–282.
EPICA Community Members. 2006. One-to-one coupling of glacial climate variability in Greenland
and Antarctica. Nature, 444(195).
Falkenroth, Achim, Degreif, Kai, & Jähne, Bernd. 2007. Visualisation of Oxygen Concentration
Fields in the Mass Boundary Layer by Fluorescence Quenching. In: Garbe, C.S., Handler, R.A., &
Jähne, B. (eds), Transport at the Air Sea Interface - Measurements, Models and Parameterizations.
Springer Verlag, this volume.
Feng, W., Chipperfield, M. P., Dorf, M., & Pfeilsticker, K. 2006. Mid-latitude Ozone Changes: Studies
with a 3-D CTM Forced by ERA-40 Analyses. Atmos. Chem. Phys. Discuss., 6, 6695–6722.
Frank, N., Kober, B., & Mangini, A. 2006. Carbonate precipitation, U-series dating, and U.isotopic
variations in a Holocene Travertine Platform at Bad Langensalza- Thuringian Basin. Quaternaire,
17(4), 321–330.
Frankenberg, C., Meirink, J. F., Bergamaschi, P., Goede, A., Heiman, M., Körner, S., Platt, U., van
Weele, M., & Wagner, T. 2006. SATELLITE CHARTOGRAPHY OF ATMOSPHERIC METHANE
FROM SCIAMACHY ON BOARD ENVISAT: ANALYSIS OF THE YEARS 2003 AND 2004. J.
Geophys. Res., 111, D07303, doi:10.1029/2005JD006235.
Friedrich, W. L., Kromer, B., Friedrich, M., Heinemeier, J., Pfeiffer, T., & S., Talamo. 2006. Santorini
Eruption Radiocarbon Dated to 1627-1600 B.C. Science, 312, 548.
Frieler, K., Rex, M., Salawitch, R. J., Canty, T., Streibel, M., Stimpfle, R. M., Pfeilsticker, K., Dorf,
M., Weisenstein, D. K., & Godin-Beekmann, S. 2006. Towards a better quantitative understanding
of polar stratospheric ozone loss. Geophys. Res. Lett., 22. doi:10.1029/2005GL025466.
Frieß, U., Monks, P.S., Remedios, J.J., Rozanov, A., Sinreich, R., Wagner, T., & Platt, U. 2006.
MAX-DOAS O4 measurements: A new technique to derive information on atmospheric aerosols.
(II) Modelling studies. Journal of Geophysical Research, 111(D14203). doi:10.1029/2005JD006618.

7.1. PEER REVIEWED PUBLICATIONS 181
Frie, F., Monks, P. S., Remedios, J. J., Rozanov, A., Sinreich, R., Wagner, T., & Platt, U. 2006.
MAX-DOAS O4 MEASUREMENTS: A NEW TECHNIQUE TO DERIVE INFORMATION ON
ATMOSPHERIC AEROSOLS. (II) MODELLING STUDIES. J. Geophys. Res., 111, D14203,
doi:10.1029/2005JD006618.
Frins, E., Bobrowski, N., Platt, U., & Wagner, T. 2006a. TOMOGRAPHIC MAX-DOAS OBSERVA-
TIONS OF SUN ILLUMINATED TARGETS: A NEW TECHNIQUE PROVIDING WELL DE-
FINED ABSORPTION PATHS IN THE BOUNDARY LAYER. Applied Optics, 45, 6227–6240.
Frins, E., Bobrowski, N., Platt, U., & Wagner, T. 2006b. Tomographic multiaxis-differential optical
absorption spectroscopy observations of Sun-illuminated targets: a technique providing well-defined
absorption paths in the boundary layer. Applied Optics, 45(24), 6227–6240.
Frisia, S., Borsato, A., Mangini, A., Sptl, C., Madonia, G., & Sauro, U. 2006. Holocene climate
variability in Sicily from a discontinuous stalagmite record and the Mesolithic to Neolithic transition.
Quaternary Research, 66, 388–400.
Gamnitzer, U., Karstens, U., Kromer, B., Neubert, R. E M., Meijer, H. A. J., Schroeder, H., & Levin,
I. 2006. Carbon monoxide: A quantitative tracer for fossil fuel CO2? J. Geophys. Res., 111,
D22302, doi:10.1029/2005JD006966.
Garbe, C. S., Handler, R. A., & Jähne, B. 2007. Transport at the Air Sea Interface - Measurements,
Models and Parameterizations. Springer. Accepted for publication.
Grzegorski, M., Wenig, M., Platt, U., Stammes, P., Fournier, N., & Wagner, T. 2006. THE HEIDEL-
BERG ITERATIVE CLOUD RETRIEVAL UTILITIES (HICRU) AND ITS APPLICATION TO
GOME DATA. Atmos. Chem. Phys., 6, 4461–4476.
Hartl, A., Song, B.C., & Pundt, I. 2006. 2-D reconstruction of atmospheric concentration peaks from
horizontal long path DOAS tomographic measurements: parametrisation and geometry within a
discrete approach. Atmospheric Chemistry and Physics, 6, 847–861.
Hendrick, F., Van Roozendael, M., Kylling, A., Petritoli, A., Rozanov, A., Sanghavi, S., Schofield,
R., von Friedeburg, C., Wagner, T., Wittrock, F., Fonteyn, D., & De Maziere, M. 2006. BrO
PROFILING FROM GROUND-BASED DOAS OBSERVATIONS: NEW TOOL FOR THE EN-
VISAT/SCIAMACHY VALIDATION. Atmos. Chem. Phys., 6, 93–108.
Jähne, B., Popp, C., Schimpf, U., & Garbe, C. S. 2007. The Influence of Intermittency on Air/Water
Gas Transfer Measurements. In: Garbe, C.S, Handler, R. A., & Jhne, B. (eds), Transport at the Air
Sea Interface-Measurements, Models and Parameterizations. Springer. Accepted for Publication.
Jehle, M., & Jähne, B. A novel method for spatio-temporal analysis of flows close to free water
surfaces. Experiments in Fluids, Special Issue for ISFV12.
Jehle, M., & Jähne, B. 2006. Direct estimation of the wall shear rate using parametric motion models
in 3D. In: Pattern Recognition, 28th DAGM.
Keene, W. C., Stutz, J., Pszenny, A. A. P., Maben, J. R., Fisher, E., Smith, A. M., von Glasow,
R., Pechtl, S., Sive, B. C., & Varner, R. K. 2006. Inorganic chlorine and bromine in coastal New
England air during summer. J. Geophys. Res., accepted.
Kern, C., Trick, S., Rippel, B., & Platt, U. 2006. Applicability of light-emitting diodes as light sources
for active DOAS measurements. Applied Optics, 45, 2077–2088.
Kilian, R., Biester, H., Behrmann, J., Baeza, O., Fesq-Martin, M., Hohner, M., Schimpf, D., Friedmann,
A., & Mangini, A. 2006. Millennium-scale volcanic impact on a superhumid and pristine
ecosystem. Geology, 34(8), 609–612.
Legrand, M., Preunkert, S., Schock, M., Cerqueira, M., Kasper-Giebl, A., Alfonso, J., Pio, C., Gelencser,
A., Etchevers, I., & Simpson, D. in press. Major 20th century changes of organic aerosol
components (BC, WinOC, DOC, HULIS, mono and dicarboxylic acids and cellulose) derived from
Alpine ice cores. Journal of Geophysical Research. CARBOSOL special issue.
Leidenberger, P., Oswald, B., & Roth, K. 2006. Efficient reconstruction of dispersive dielectric profiles
using time domain reflectrometry (TDR). Hydrol. Earth Syst. Sci., 10, 209–232.

182 CHAPTER 7. BIBLIOGRAPHY
Leigh, R. J., Corlett, G. K., Frieß, U., & Monks, P. S. 2006. concurrent multi axie differential optical
absorption spectroscopy system for the measurement of tropospheric nitrogen dioxide. Applied
Optics, 45(28), 7504–7518.
Levin, I., & Karstens, U. 2006. Inferring high-resolution fossil fuel CO2 records at continental sites
from combined 14 CO2 and CO observations. accepted for publication in Tellus B.
Loyola, D., Valks, P., Ruppert, T., Richter, A., Wagner, T., van der A, R., & Meisner, R. 2006.
THE 1997 EL NIÑO IMPACT ON CLOUDS, WATER VAPOUR, AEROSOLS AND REACTIVE
TRACE GASES IN THE TROPOSPHERE, AS MEASURED BY THE GLOBAL OZONE MON-
ITORING EXPERIMENT. Advances in Geosciences, 6, 267 272.
Manning, S.W., Ramsey, C.B., Kutschera, W., Higham, T., Kromer, B., Steier, P., & E.M., Wild.
2006. Chronology for the Aegean Late Bronze Age 1700-1400 B.C. Science, 312, 565–569.
Mettendorf, K.U., Hartl, A., & Pundt, I. 2006. An Indoor Test Campaign of the Tomography Long
Path Differential Optical Absorption Spectroscopy (DOAS) Technique. Journal of Environmental
Monitoring, 8, 279–287.
Meyer, R., Büll, R., Leiter, C., Mannstein, H., Pechtl, S., Oki, T., & Wendling, P. 2006. Contrail
observations over Southern and Eastern Asia in NOAA/AVHRR data and intercomparison to contrail
simulations in a GCM. Int. J. Remote Sensing, in press, Also available as Report No. 176,
Institut für Physik der Atmosphäre, DLR Oberpfaffenhofen.
Naegler, T., & Levin, I. 2006. Closing the Global Radiocarbon Budget 1945-2005. J. Geophys. Res.,
111, D12311, doi:10.1029/2005JD006758.
Naegler, T., Ciais, P., Rodgers, K., & Levin, I. 2006a. Excess radiocarbon constraints on airsea
gas exchange and the uptake of CO2 by the oceans. Geophys. Res. Letters, 33, L11802,
doi:10.1029/2005GL025408.
Naegler, T., Ciais, P., Orr, J. C., Aumont, O., & Rödenbeck, C. 2006b. On evaluating ocean models
with atmospheric potential oxygen. TELLUS, (in press).
Oppenheimer, C., Tsanev, V. I., Braban, C. F., Cox, R. A., Adams, J. W., Aiuppa, A., Bobrowski, N.,
Delmelle, P., Barclay, J., & McGonigle, A. J. 2006. BrO formation in volcanic plumes. Geochimica
et Cosmochimica Acta, 70, 2935–2941.
Pechtl, S., Schmitz, G., & von Glasow, R. 2006a. Modeling iodide iodate speciation in atmospheric
aerosol. Atmos. Chem. Phys. Discuss., 6, 10959 – 10989.
Pechtl, S., Lovejoy, E. R., Burkholder, J. B., & von Glasow, R. 2006b. Modeling the possible role of
iodine oxides in atmospheric new particle formation. Atmos. Chem. Phys., 6, 503 – 523.
Piel, C., Weller, R., M.Huke, & Wagenbach, D. 2006. Atmospheric methane sulfonate and non-sea
salt sulfate records at the EPICA deep-drilling site in Dronning Maud Land. Journal of Geophysical
Research.
Ponater, M., Pechtl, S., Sausen, R., Schumann, U., & Hüttig, G. 2006. A state-of-the-art assessment
of the potential of the cryoplane technology to reduce aircraft climate impact. Atmos. Environment,
40, 6928 – 6944.
Rezanezhad, F, Vogel, H.-J., & Roth, K. 2006. Experimental study of fingered flow through initially
dry sand. Hydrol. Earth Syst. Sci. Discuss., 3, 2595–2620.
Rohs, S., Schiller, C., Riese, M., Engel, A., Schmidt, U., Wetter, T., Levin, I., Nakazawa, T., & Aoki,
S. 2006. Long-term changes of methane and hydrogen in the stratosphere in the period 1978-2003.
J. Geophys. Res., 111, D14315, doi:10.1029/2005JD006877.
Schimpf, U., Frew, N., & Jähne, B. 2006. Infrared Imaging: A novel tool to investigate the influence
of surface slicks on air sea gas exchange. In: Gade, M., Hühnerfuss, H., & Korenowski, G.M. (eds),
Marine Surface Films: Chemical Characteristics, Influence on Air-Sea Interactions, and Remote
Sensing. Springer.
Schneider, Klaus, Ippisch, Olaf, & Roth, Kurt. 2006. Novel evaporation experiment to determine soil
hydraulic properties. 10, 817–827.

7.1. PEER REVIEWED PUBLICATIONS 183
Schofield, R., Johnston, P. V., Thomas, A., Kreher, K., Connor, B. J., Wood, S., Shooter, D., Chipperfield,
M. P., Richter, A., von Glasow, R., & Rodgers, C. D. 2006. Tropospheric and stratospheric
BrO columns over Arrival Heights, Antarctica during the spring polar vortex split, 2002. J. Geophys.
Res., 111, D22310, doi:10.1029/2005JD007022.
Scholl, T., Pfeilsticker, K., Davis, A. B., Klein Baltink, H., Crewell, S., Löhnert, U., Simmer, C.,
Meywerk, J., & Quante, M. 2006. Path length distributions for solar photons under cloudy skies:
Comparison of measured first and second moments with predictions from classical and anomalous
diffusion theories. J. Geophys. Res., 111, D12211. doi:10.1029/2004JD005707.
Scholz, D., & Mangini, A. 2006. U-redistribution in fossil reef corals from Barbados, West Indies, and
sea level reconstruction for MIS 6.5. The climate of past Interglacials. in press.
Sioris, C. E., Kovalenko, L. J., McLinden, C. A., Salawitch, R. J., Van Roozendael, M., Goutail,
F., Dorf, M., Pfeilsticker, K., Chance, K., von Savigny, C., Liu, X., Kurosu, T. P., Pommereau,
J.-P., Bösch, H., & Frerick, J. 2006. Latitudinal and vertical distribution of bromine monoxide in
the lower stratosphere from SCIAMACHY limb scattering measurements. J. Geophys. Res., 111,
D14301. doi:10.1029/2005JD006479.
Smoydzin, L., & von Glasow, R. 2006. Do organic surface films on sea salt aerosols influence atmospheric
chemistry? A model study. Atmos. Chem. Phys. Discuss., 6, 10373 – 10402.
Spötl, C., & Mangini, A. 2006. U/Th age constraints on the absence of ice in the central Inn Valley
(eastern Alps, Austria) during Marine Isotope Stages 5c to 5a. Quaternary Research, 66, 167–175.
Spötl, C., Mangini, A., & Richards, D.A. 2006. Chronology and paleoenvironment of Marine Isotope
Stage 3 from two high-elevation speleothems, Austrian Alps. Quaternary Science Reviews, 25,
1127–1136.
Steier, P., Drosg, R., Fedi, M., Kutschera, W., Schock, M., Wagenbach, D., & Wild, E.M. 2006.
Radiocarbon determination of particulated organic carbon in non-temperated, alpine glacier ice.
Radiocarbon, 48(1), 69–82.
Toenges-Schuller, N., Stein, O., Rohrer, F., Wahner, A., Richter, A., Burrows, J. P., Beirle, S.,
Wagner, T., Platt, U., & Elvidge, C. D. 2006. GLOBAL DISTRIBUTION PATTERN OF AN-
THROPOGENIC NITROGEN OXIDE EMISSIONS: CORRELATION ANALYSIS OF SATEL-
LITE MEASUREMENTS AND MODEL CALCULATIONS. J. Geophys. Res., 111, D05312,
doi:10.1029/2005JD006068.
Usoskin, I.G., Solanki, S.K., Kovaltsov, G.A., Beer, J., & Kromer, B. 2006. Solar proton events in
cosmogenic isotope data. Geophys. Res. Lett., 33.
Vollweiler, N., Scholz, D., Mühlinghaus, C., Mangini, A., & Spötl, C. 2006. A precisely dated climate
record for the last 9 kyr from three high alpine stalagmites, Spannagel Cave, Austria. Geophysical
Research Letters, 33, L20703.
von Glasow, R. 2006. Importance of the surface reaction OH + Cl − on sea salt aerosol for the
chemistry of the marine boundary layer - a model study. Atmos. Chem. Phys., 6, 3571 – 3581.
von Glasow, R., & Crutzen, P. J. 2006. Tropospheric halogen chemistry. In: The Atmosphere (ed. R.
F. Keeling), Vol. 4 Treatise on Geochemistry (eds. H. D. Holland and K. K. Turekian), in press.
Elsevier-Pergamon, Oxford.
von Rohden, C., Wunderle, K., & Ilmberger, J. 2006. Parametrization of the vertical transport in a
small thermally stratified lake. aquatic sciences accepted.
Wagner, T., Beirle, S., Grzegorski, M., & Platt. 2006a. GLOBAL TRENDS (1996 TO 2003)
OF TOTAL COLUMN PRECIPITABLE WATER OBSERVED BY GOME ON ERS-2 AND
THEIR RELATION TO SURFACE TEMPERATURE. J. Geophys. Res., 111, D12102,
doi:10.1029/2005JD006523.
Wagner, T., Beirle, S., Deutschmann, T., Grzegorski, M., & Platt. 2006b. SATELLITE MONITOR-
ING OF DIFFERENT VEGETATION TYPES BY DIFFERENTIAL OPTICAL ABSORPTION
SPECTROSCOPY (DOAS) IN THE RED SPECTRAL RANGE. Atmos. Chem. Phys., accepted.

184 CHAPTER 7. BIBLIOGRAPHY
Wang, P., Richter, A., Bruns, M., Burrows, J.P., Scheele, R., Junkermann, W., Heue, K.-P., Wagner,
T., Platt, U., & Pundt, I. 2006a. Airborne multi-axis DOAS measurements of tropospheric SO2
plumes in the Po-valley, Italy. Atmospheric Chemistry and Physics, 6, 329–338.
Wang, P., Richter, A., Bruns, M., Burrows, J. P., Junkermann, W., Heue, K.-P., Wagner, T., Platt, U.,
& Pundt, I. 2006b. AIRBORNE MULTI-AXIS DOAS MEASUREMENTS OF TROPOSPHERIC
SO2 PLUMES IN THE PO-VALLEY, ITALY. Atmos. Chem. Phys., 6, 329338.
Wittrock, F., Richter, A., Oetjen, H., Burrows, J. P., Kanakidou, M., Myriokefalitakis, S., Volkamer,
R., Beirle, S., Platt, U., & Wagner, T. 2006. SIMULTANEOUS GLOBAL OBSERVA-
TIONS OF GLYOXAL AND FORMALDEHYDE FROM SPACE. Geophys. Res. Lett., 33, L16804,
doi:10.1029/2006GL026310.
WMO (ed). 2006a. Scientific Assessment of Ozone Depletion: 2006. World Meteorological Organization
Global Ozone Research and Monitoring Project: Geneva.
WMO (ed). 2006b. Scientific Assessment of Ozone Depletion: 2006. World Meteorological Organization
Global Ozone Research and Monitoring Project: Geneva.
Wolff, E.W., Fischer, H., Fundel, F., Ruth, U., Twarloh, B., Littot, G.C., Mulvaney, R., Röthlisberger,
R., De Angelis, M., Boutron, C.F., Hansson, M., Jonsell, U., Hutterli, M.A., Lambert, F., Kaufmann,
P., Stauffer, B., Stocker, T.F., Steffensen, J.P., Bigler, M., Siggaard-Andersen, M.L., Udisti,
R., Becagli, S., Castellano, E., Severi, M., Wagenbach, D., Barbante, C., Gabrielli, P., & Gaspari,
V. 2006. Southern Ocean sea-ice extent, productivity and iron flux over the past eight glacial cycles.
Nature, 440(7083), 491–496.
Wollschläger, U., Ilmberger, J., Isenbeck-Schrter, M., Kreuzer, A., von Rohden, C., Roth, K., &
Schäfer, W. 2006. Coupling of groundwater and surface water at Lake Willersinnweiher: Groundwater
modelling and tracer studies. aquatic sciences accepted.

7.2. GREY PUBLICATIONS 185
Grey Publications
Barkly, M.P., Frieß, U., & Monks, P.S. 2006. Measuring atmospheric CO2 from space using Full
Spectral Initiation (FSI) WFM-DOAS. Atmospheric Chemistry and Physics Discussion, 6, 2765–
2807.
Beirle, S., Volkamer, R., Wittrock, F., Richter, A., Burrows, J., Platt, U., & Wagner,
T. 2006. DOAS RETRIEVAL OF GLYOXAL FROM SPACE. Proceedings of
the ESA Atmospheric Science Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy,
http://earth.esa.int/workshops/atmos2006/participants/1055/paper DOAS retrieval of Glyoxal from space.pdf.
Bobrowski, N., Burton, M.R., Caltabiano, T., Salerno, G., & Platt, U. 2006. Measurements of
the Halogen and SO2 Flux from Mt. Etna in September 2003. Geophysical Research Letters. in
preparation.
Butz, A., Bösch, H., Camy-Peyret, C., Dorf, M., Engel, A., Payan, S., & Pfeilsticker, K. 2006.
Observational constraints on the kinetics of the ClO-BrO and ClO-ClO ozone loss cycles in the
Arctic winter stratosphere. Geophys. Res. Lett. submitted.
Deutschmann, T., & Wagner, T. 2006. TRACY-II Users Manual.
Frieler, K., Rex, M., Salawitch, R.J., Canty, T., Streibel, M., Stimpfle, R.M., Pfeilsticker, K., Dorf,
M., Weisenstein, D.K.and Godin-Beekmann, S., & von der Gathen, P. 2006. Towards a better quantitative
understanding of polar stratospheric ozone loss. Geophysical Research Letters. submitted.
Frieß, U., & Platt, U. 2006a. Absolute concentration measurements by DOAS at ”Zero Visibility”. in
preparation.
Frieß, U., & Platt, U. 2006b. Tropospheric IO in the Antarctic Coastal Region - Observations by
Multi-Axis DOAS. in preparation.
Garbe, C. S., Roetmann, K., & Jähne, B. 2006a. An Optical Flow Based Technique for the Non-
Invasive Measurement of Microfluidic Flows. Pages 1–10 of: 12TH INTERNATIONAL SYMPO-
SIUM ON FLOWVISUALIZATION.
Garbe, C. S., Roetmann, K., & Jhne, B. 2006b. An Optical Flow Based Technique for the Non-
Invasive Measurement of Microfluidic Flows. Pages 1–10 of: 12th International Symposium on
Flow Visualization.
Garbe, C. S., Degreif, K., & Jhne, B. 2006c. Viscous stress measurements from active thermography
on a free air-water interface. Pages 1–10 of: International Symposium on Transport at the Air-Sea
Interface.
Hendrick, F., Van Roozendael, M., De Maziere, M., Richter, A., Rozanov, A., Sioris, C., Dorf, M.,
Kühl, S., Pukite, J., Wagner, T., & Goutail, F. 2006. BrO PROFILING FROM GROUND-BASED
DOAS OBSERVATIONS: NEW TOOL FOR THE ENVISAT/SCIAMACHY VALIDATION. proceedings
of the ESA Atmospheric Science Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy,
http://earth.esa.int/workshops/atmos2006/participants/873/paper hendrick esa conf06.pdf.
Jähne, B. 2007a. Complex Motion. Springer. LNCS 3417.
Jähne, B. 2007b. Complex Motion in Environmental Physics and Live Sciences. Pages 92–105 of:
Jhne, B. (ed), Complex Motion. Springer. LNCS 3417.
Jehle, M., Klar, M., & Jähne, B. in preparation. Optical-Flow based velocity analysis. In: Tropea, C.,
Foss, J., & Yarin, A. (eds), Springer Handbook of Experimental Fluid Dynamics. Berlin, Heidelberg:
Springer.
Kreuzer, A. M., Zongyu, C., Kipfer, R., & Aeschbach-Hertig, W. 2006. Environmental Tracers in
Groundwater of the North China Plain. Pages 136–139 of: IAEA (ed), Isotopes in Environmental
Studies - Aquatic Forum 2004. Vienna: IAEA.
Kühl, S., Pukite, J., Deutschmann, T., Platt, U., & Wagner, T. 2006a. SCIAMACHY Limb Measurements
of NO2, BrO and OClO. Retrieval of vertical profiles: Algorithm, first results and validation.
Adv. Space Res., in review.

186 CHAPTER 7. BIBLIOGRAPHY
Kühl, S., Pukite, J., Deutschmann, T., Dorf, M., Hendrick, F., Platt, U., & Wagner, T. 2006b.
STRATOSPHERIC OClO AND BrO PROFILES FROM SCIAMACHY LIMB MEASUREMENTS.
Proceedings of the ACVE-3 Workshop, 4 7 December, Frascati, Italy, 2006.
Lee, J. S., Kim, Y. J., Geyer, A., & Platt, U. 2006. Simultaneous Measurements of Atmospheric Trace
Gases and Atmospheric Visibility by DOAS System. in preparation.
Levin, I., & Karstens, U. 2006. Quantifying fossil fuel CO2 over Europe. In: Dolman, A. J., Freibauer,
A., & Valentini, R. (eds), Observing the Continental Scale Greenhouse Gas Balance of Europe.
Heidelberg, Germany: Springer-Verlag, Ecological Studies Series.
Louban, I, Bobrowski, N., Rouwet, D., Inguaggiato, S., & Platt, U. 2006. Imaging DOAS for Volcanological
Applications. in preparation.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006a. IDENTIFICATION OF HCHO SOURCES
DUE TO ISOPRENE OR/AND BIOMASS BURNING EMISSIONS USING COMBINED HCHO
AND NO2 SATELLITE OBSERVATIONS. 36th COSPAR Scientific Assembly Abstracts, A1.1-
0063.06.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006b. ISOPRENE AND BIOMASS BURNING
EMISSIONS FROM SATELLITE OBSERVATIONS: SYNERGISTIC USE OF HCHO AND NO2
TRACE GAS MEASUREMENTS. ESA Atmospheric Science Conference abstract book.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006c. ISOPRENE AND BIOMASS BURNING
EMISSIONS FROM SATELLITE OBSERVATIONS: SYNERGISTIC USE OF HCHO AND NO2
TRACE GAS MEASUREMENTS. Geophysical Research Abstracts, 8, 07665.
Marbach, T., Beirle, S., Platt, U., & Wagner, T. 2006d. ISOPRENE AND BIOMASS BURNING
EMISSIONS FROM SATELLITE OBSERVATIONS: SYNERGISTIC USE OF HCHO AND NO2
TRACE GAS MEASUREMENTS. 3rd International DOAS Workshop abs. Vol.
N., Bobrowski, & U., Platt. 2006. Bromine Monoxide Studies in Volcanic Plumes. Journal of Volcanology
and Geothermal Research. submitted 31. 7. 2005.
Pettinger, M., Jahn, F., Wagenbach, D., Bhlert, R., Hoelzle, M., & Preunkert, S. 2006. Climate
significance of stable water isotope records from Alpine ice cores. Geophysical Research Abstracts,
Vol. 8, 09854. Poster.
Platt, U., Pfeilsticker, K., & Vollmer, M. 2006. Chapter 24: Atmospheric Optics. In: Träger, F. (ed),
Springer Handbook of Lasers and Optics. Heidelberg: Springer.
Pukite, J., Kühl, S., Deutschmann, T., Wilms-Grabe, W., Platt, U., & Wagner, T. 2006a. LIMB
RETRIEVAL OF STRATOSPHERIC TRACE GASES FROM SCIAMACHY USING MONTE
CARLO RADIATIVE TRANSFER MODELING. 3rd International DOAS Workshop abs. Vol.
Pukite, J., Kühl, S., Deutschmann, T., Wilms-Grabe, W., Friedeburg, C., Platt,
U., & Wagner, T. 2006b. RETRIEVAL OF STRATOSPHERIC TRACE GASES
FROM SCIAMACHY LIMB MEASUREMENTS. Proceedings of the ESA Atmospheric
Science Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy,
http://earth.esa.int/workshops/atmos2006/participants/1148/paper proc Frasc 2.pdf.
Pukite, J., Kühl, S., Deutschmann, T., Wilms-Grabe, W., Friedeburg, C., Platt, U., & Wagner,
T. 2006c. RETRIEVAL OF STRATOSPHERIC TRACE GASES FROM SCIAMACHY LIMB
MEASUREMENTS. Geophysical Research Abstracts, 8, 08102.
Rocholz, Roland. 2006. Imaging System for combined slope/height measurements of short wind
waves : ISHG. In: DPG Frhjahrstagung, Heidelberg, 03.2006 (ed), Verhandlungen der Deutschen
Physikalischen Gesellschaft. Deutsche Physikalische Gesellschaft.
Schimpf, U., Popp, C., & Jähne, B. 2006. Active Thermography: a local and fast method to investigate
heat and gas exchange between ocean and atmosphere. In: DPG Frhjahrstagung, Heidelberg, 15.-
17.03.2006 (ed), Verhandlungen der Deutschen Physikalischen Gesellschaft. Deutsche Physikalische
Gesellschaft.
Sebastian, O., Geyer, A., Hönninger, G., Platt, U., Sciare, J., & Mihalopoulos, N. 2006. The influence
of radicals on DMS oxidation in the Eastern Mediterranean marine boundary layer. in preparation.

7.2. GREY PUBLICATIONS 187
Simpson, W.R., Carlson, D., Hönninger, G., Douglas, T.A., Sturm, M., Perovich, D., & Platt, U.
2006. First-year sea-ice contact predicts bromine monoxide (BrO) levels better than potential frost
flower contact. Atmospheric Chemistry and Physics Discussion, 6, 1105111066.
Sinreich, R., Volkamer, R., Filsinger, F., Frieß, U., Kern, C., Platt, U., Sebastián, O., & Wagner,
T. 2006a. MAX-DOAS detection of glyoxal during ICARTT 2004. Atmospheric Chemistry and
Physics Discussion, 6, 9459–9481.
Sinreich, R., Volkamer, R., Filsinger, F., Frie, U., Kern, C., Platt, U., Sebastian, O., & Wagner, T.
2006b. MAX-DOAS DETECTION OF GLYOXAL DURING ICARTT 2004. Atmos. Chem. Phys.
Discuss., 6, 9459–9481.
Spötl, C., & Mangini, A. 2005. Altersbestimmungen an Griffner Tropfsteinen. Page 336pp of: Komposch,
C., & Wieser, C. (eds), Schlossberg Griffen: Klagenfurt. Verlag des Naturwissenschaftlichen
Vereins fr Kärnten.
Stutz, J., Hebestreit, K., Hönninger, G., & U., Platt. 2006. Simultaneous measurement of iodine oxide
and nitrogen dioxide at Mace Head, Ireland. in preparation.
Wagner, T., Beirle, S., Deutschmann, T., Frankenberg, C., Grzegorski, M., Hollwedel, J., Khokhar,
M. F., Kühl, S., Marbach, T., Platt, U., Pukite, J., Sanghavi, S., & Wilms-Grabe, W. 2006a. 10
YEARS OF REMOTE SENSING WITH MODERN UV/VIS/NIR SATELLITE INSTRUMENTS:
A NEW VIEW ON GLOBAL NEAR-SURFACE TRACE GAS DISTRIBUTIONS. presentation at
the 36TH COSPAR SCIENTIFIC ASSEMBLY BEIJING, CHINA, 16 23 JULY 2006.
Wagner, T., Beirle, S., Grzegorski, M., & Platt, U. 2006b. CHARACTERIZATION OF
VEGETATION TYPE USING DOAS SATELLITE RETRIEVALS. poster presentation
at the ESA Atmospheric Science Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy
(http://earth.esa.int/workshops/atmos2006/participants/563/paper Thomas Wagner vegetation frascati.pdf).
Wagner, T., Burrows, J. P., Deutschmann, T., Dix, B., Hendrick, F., v.Friedeburg, C., Frie, U., Heue,
K.-P., Irie, H., Iwabuchi, H., Kanaya, Y., Keller, J., McLinden, C. A., Oetjen, H., Palazzi, E.,
Petritoli, A., Platt, U., Postylyakov, O., Pukite, J., Richter, A., van Roozendael, M., Rozanov,
A., Rozanov, V., Sinreich, R., Sanghavi, S., & F., Wittrock. 2006c. COMPARISON OF BOX-
AIR-MASS-FACTORS AND RADIANCES FOR MULTIPLE-AXIS DIFFERENTIAL OPTICAL
ABSORPTION SPECTROSCOPY (MAX-DOAS) GEOMETRIES CALCULATED FROM DIF-
FERENT UV/VISIBLE RADIATIVE TRANSFER MODELS. J. Atmos. Chem. Phys. Discuss.,
6, 9823–9876.
Wagner, T., Ibrahim, O., Sinreich, R., Frie, U., & Platt. 2006d. ENHANCED TROPOSPHERIC BRO
CONCENTRATIONS OVER THE ANTARCTIC SEA ICE BELT IN MID WINTER OBSERVED
FROM MAX-DOAS OBSERVATIONS ON BOARD THE RESEARCH VESSEL POLARSTERN.
Atmos. Phys. Chem., submitted.
Wagner, T., Beirle, S., Grzegorski, M., & Platt, U. 2006e. GLOBAL TRENDS OF CLOUD COVER
AND CLOUD HEIGHT DERIVED FROM GOME SATELLITE OBSERVATIONS 1996-2003 AND
THEIR RELATION TO SURFACE-NEAR TEMPERATURE. poster presentation at the 2006 Fall
Meeting: 1115 December 2006, San Francisco, California.
Wagner, T., Beirle, S., Grzegorski, M., & Platt, U. 2006f. INVESTIGATING THE EARTH’S HYDRO-
LOGICAL CYCLE USING H2O VCDS AND CLOUD RELATED PARAMETERS FROM GOME-
II. Proceedings of the 1st EPS/MetOp RAO Workshop ESRIN, Frascati, Italy, 15-17 May 2006
(http://earth.esrin.esa.it/workshops/EPS MetOp RAO 2006/proceedings/papers/p wagne.pdf).
Wagner, T., Beirle, S., Deutschmann, T., Grzegorski, M., Sanghavi, S., & Platt, U.
2006g. PROBING INTERNAL CLOUD PROPERTIES FROM SPACE. presentation at
the ESA Atmospheric Science Conference, 8-12 May 2006, ESA ESRIN, Frascati, Italy
(http://earth.esa.int/workshops/atmos2006/participants/565/paper Thomas Wagner cloud properties frascati.p
Wagner, T., Beirle, S., Deutschmann, T., Grzegorski, M., Sanghavi, S., & Platt, U. 2006h. PROB-
ING INTERNAL CLOUD PROPERTIES FROM SPACE. presentation at the 36TH COSPAR
SCIENTIFIC ASSEMBLY BEIJING, CHINA, 16 23 JULY 2006.
Xie, P., Geyer, A., Volkamer, R., Yu, Y., Platt, U., Galle, B., & Chen, L. 2006. Investigation of the
distribution of aromatic hydrocarbons in Shanghai (China). in preparation.

7.3. PHD THESES 189
PhD Theses
Bossmeyee, Jens. 2006. Studies of Aldehydes in an Atmosphere Simulation Chamber, Degradation of
Higher Aldehydes by Nitrate Radicals. PhD Thesis, Universität Heidelberg.
Braun, H. 2006a. A new hypothesis for the 1470-year cycle of abrupt warming events in the last
ice-age. Ph.D. thesis, Ruprecht-Karls-University, Heidelberg.
Braun, H. 2006b. A new hypothesis for the 1470-year cycle of abrupt warming events in the last
ice-age. PhD Thesis, Universität Heidelberg.
Butz, A. 2006. Case studies of stratospheric nitrogen, chlorine and iodine photochemistry based on
balloon-boren UV/visible and IR absorption spectroscopy. PhD Thesis, Universität Heidelberg.
Degreif, K. A. 2006. Untersuchungen zum Gasaustausch - Entwicklung und Applikation eines zeitlich
aufgelsten Massenbilanzverfahrens. PhD Thesis, Universität Heidelberg.
Hak, Claudia. 2006. VARIABILITT VON FORMALDEHYD-KONZENTRATIONEN IN DER VER-
SCHMUTZTEN PLANETAREN GRENZSCHICHT: MESSUNGEN IM BALLUNGSRAUM VON
MILANO. PhD Thesis, Universität Karlsruhe.
Jehle, M. 2006. Spatio-temporal analysis of flows close to water surfaces. PhD Thesis, Universität
Heidelberg.
Khokhar, M. F. 2006. RETRIEVAL AND INTERPRETATION OF TROPOSPHERIC SO2 FROM
UV-VIS SATELLITE INSTRUMENTS. PhD Thesis, University of Leipzig.
Kraus, S. 2006. Entwicklung eines flexiblen Softwaresystems zur Auswertung spektroskopischer
Satelliten-Bildsequenzen. PhD Thesis, Technische Informatik, Universität Mannheim.
Latuske, N. 2006. Solare Variabilitt und Klimaänderungen auf einer Zeitskala von einigen Dekaden
bis Jahrhunderten im Holozän. Ph.D. thesis, Ruprecht-Karls-University, Heidelberg.
Lotter, A. 2006. Field Measurements of Water Continuum and Water Dimer Absorption by Active
Long Path Differential Optical Absorption Spectroscopy (DOAS). PhD Thesis, Universität Heidelberg.
Popp, C. J. 2006. Untersuchung von Austauschprozessen an der Wasseroberfläche aus Infrarot-
Bildsequenzen mittels frequenzmodulierter Wärmeeinstrahlung. PhD Thesis, Universität Heidelberg.
Scholl, T. 2006. Photon Path Length Distributions for Cloudy Skies - Their first and second-order
moments inferred from high resolution oxygen A-Band spectroscopy. PhD Thesis, Universität Heidelberg.
Unkel, I. 2006. AMS- 14 C-Analysen zur Rekonstruktion der Landschafts- und Kulturgeschichte in der
Region Palpa (S-Peru). Ph.D. thesis, Ruprecht-Karls-University, Heidelberg.

7.4. DIPLOMA THESES 191
Diploma Theses
Jahn, F. 2006. Einsatz der Continous Flow Analysis zur vorläufigen Datierung eines alpinen Eiskerns.
diploma thesis, Universität Heidelberg.
Mühlinghaus, C. 2006. Modellierung paläoklimatischer Parameter anhand Wachstum und Isotopiekorrelationen
von Stalagmiten. diploma thesis, Universität Heidelberg.
Rocholz, A. 2005. Bildgebendes System zur simultanen Neigungs- und Höhenmessung an kleinskaligen
Wind-Wasser-Wellen. diploma thesis, Universität Heidelberg.
Schneider, Klaus. 2005. Novel evaporation experiment to determine soil hydraulic properties. diploma
thesis, Universität Heidelberg.
Studiosus, A. 2006a. Development of a new technique to measure everytjing everywhere. diploma
thesis, Universität Heidelberg.
Studiosus, A. 2006b. Development of a new technique to measure everytjing everywhere. diploma
thesis, Universität Heidelberg.
Vogel, F. 2006. Raman- and UV-Spectroscopy of liquids and dissolved volatile gases for gas-exchange
measurements. diploma thesis, Universität Heidelberg.
Vollweiler, N. 2005. Stalagmiten aus der Spannagel-Höhle bei Hintertux (Tirol, Österreich) - Archive
für das Klima der Alpen im Holozän. diploma thesis, Universität Heidelberg.
Wieser, M. 2006. Entwicklung und Anwendung von Diffusionssamplern zur Beprobung gelöster Edelgase
in Wasser. diploma thesis, Universität Heidelberg.

7.5. INVITED TALKS 193
Invited Talks
Aeschbach-Hertig, W. 2006a. Edelgase im Grundwasser als Tracer und Klimaindikatoren. Invited
talk, Kolloquium Erdwissenschaften, University of Basel, Switzerland.
Aeschbach-Hertig, W. 2006b. Edelgase und ”Excess Air” im Grundwasser. Invited talk, Hydrologisches
Kolloquium, University of Freiburg, Germany.
Aeschbach-Hertig, W. 2006c. Environmental tracers in groundwater studies - Case study North China
Plain. Invited talk, School of Environmental Science and Engineering, Chang’an University, Xi’an,
China.
Aeschbach-Hertig, W. 2006d. Groundwater age dating with gas tracers: The role of gas partitioning.
Invited key presentation, Annual Meeting of the Geological Society of America (GSA), Philadelphia,
USA.
Aeschbach-Hertig, W. 2006e. Spurenstoffmethoden zur Erforschung des Grundwassers. Invited talk,
Rhein-Neckar Gesprächskreis, Heidelberg, Germany.
von Glasow, R. 2006. Halogens in the marine boundary layer. Invited talk, UK SOLAS meeting,
Manchester, 17. - 18. July 2006.

Institut für Umweltphysik
Im Neuenheimer Feld 229
69120 Heidelberg
Germany
Tel. + 49 6221 54-63 50
Fax + 49 6221 54-64 05
email: sekretariat@iup.uni-heidelberg.de
www.iup.uni-heidelberg.de
Board of Directors
Prof. Dr. Ulrich Platt
Prof. Dr. Kurt Roth