Global Change Abstracts The Swiss Contribution - SCNAT

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predict, minimize and ensure reproducibility of
artifacts caused by gaseous organic compounds
sorbing to fiber filters..
Atmospheric Environment, 2007, V41, N37, DEC,
pp 8241-8252.
08.1-4
Interference of organic signals in highly time
resolved nitrate measurements by low mass
resolution aerosol mass spectrometry
Bae M S, Schwab F J, Zhang Q, Hogrefe O,
Demerjian K L, Weimer A, Rhoads K, Orsini D,
Venkatachari P, Hopke P K
USA, Switzerland
Meteorology & Atmospheric Sciences ,
Urban Studies
Highly time resolved measurements of nitrate in
ambient aerosols were conducted by an Aerodyne
Quadrupole Aerosol Mass Spectrometer (Q-AMS
or simply AMS) and a particle-into-liquid sampler
(PILS) coupled to ion chromatography from field
intensives at two sites: an urban site in New York
City (Queens College; QC) for wintertime (22 January
to 5 February 2004) and a rural site in southwestern
New York state (Pinnacle State Park; PSP)
for summertime (18 July to 6 August 2004). In this
study, we report that in rural atmospheres the
inorganic nitrate signal from Q-AMS may contain
significant interferences from organic signals.
Analysis of the QC data indicates a good agreement
between the PILS-nitrate and AMS-nitrate
measurements (R-2 = 0.94; linear regression slope
= 1.05). In addition, the m/z 30 and m/z 46 (two
dominant ion fragments in nitrate mass spectrum)
signals tightly correlate at QC (R-2 = 0.98)
and have an average ratio similar to that determined
in the laboratory for NH 4NO 3 (m/z 30/m/z
46 = 2.4). In contrast, at the PSP site the correlation
between PILS- and AMS- nitrate was poor
(R-2 = 0.34), the AMS reported nitrate values were
substantially higher, and the m/z 30 to m/z 46 ratios
were generally much larger than 2.4. These
observations, together with evaluations by aerosol
phase ion balance, indicate that the AMS m/z
30 signals at PSP have been strongly influenced
by organic compounds that also produce signals
at m/z 30, e. g., organic nitrates (NO+), oxygenated
organics (CH 2O+), hydrocarbon-like organics
(C2H6+), and nitrogen- containing organic compounds
(CH 4N+).
Journal of Geophysical Research Atmospheres,
2007, V112, ND22, NOV 24 ARTN: D22305.
Global Change Abstracts – The Swiss Contribution | Atmosphere
08.1-5
Small-scale cloud processes and climate
Baker M B, Peter T
USA, Switzerland
Meteorology & Atmospheric Sciences
Clouds constitute the largest single source of
uncertainty in climate prediction. A better understanding
of small- scale cloud processes could
shed light on the role of clouds in the climate system.
Nature, 2008, V451, N7176, JAN 17, pp 299-300.
08.1-6
Chemical analysis of atmospheric aerosols
Baltensperger U, Prevot A S H
Switzerland
Meteorology & Atmospheric Sciences ,
Urban Studies
Analytical and Bioanalytical Chemistry, 2008, V390,
N1, JAN, pp 277-280.
08.1-7
Entering into the “greenhouse century”:
Recent record temperatures in Switzerland are
comparable to the upper temperature quantiles
in a greenhouse climate
Beniston M
Switzerland
Modelling , Meteorology & Atmospheric Sciences
This paper investigates the recent spate of recordbreaking
warm seasons that have affected Switzerland
in less than a decade and compares the
seasonal statistics to those simulated for a ‘’greenhouse-gas’’
climate by the end of the 21st century.
The peaks of minimum and maximum temperatures
observed during some the record seasons
enter well into the 25%-75% temperature quantile
range for the scenario climate simulated by a
set of regional climate models. The anomalously
warm seasons allow a ‘’preview’’ of conditions
that may occur with greater frequency in the future.
The use of current data as a form of proxy
for the future enables an assessment of the possible
impacts on the natural and socio-economic
environments, and can help in considering possible
adaptation strategies to reduce some of the
associated risks of climatic change.
Geophysical Research Letters, 2007, V34, N16,
AUG 30 ARTN: L16710.