NATIONAL REPORT OF THE FEDERAL REPUBLIC OF ... - IAG Office

The Global Geodetic Observing System
(GGOS)
The Global Geodetic Observing System (GGOS) has been
established by the International Association of Geodesy
(IAG) as an IAG Project in July 2003 at the IUGG General
Assembly in Sapporo, Japan. In April 2004 the IAG,
represented by GGOS, has become a participating organization
of the Group on Earth Observation (GEO) and in May
2006 GGOS was accepted as a member of the Integrated
Global Observation Strategy Partnership (IGOS-P). GGOS
is thus the geodetic component of the Global Earth Observing
System of Systems (GEOSS) that integrates all the
major observing systems, i.e., the Global Ocean Observing
System (GOOS), the Global Climate Observing System
(GCOS), the Global Terrestrial Observing System (GTOS),
and GGOS.
After the first years devoted to the definition of the internal
organizational structure of GGOS and its relationship with
external organizations, it is planned to transform the GGOS
Project into a permanent element of the IAG structure at
the same level as the IAG Services and IAG Commissions
at the IUGG General Assembly 2007 in Perugia.
GGOS is the contribution of geodesy to a global Earth
monitoring system. In particular, it provides the metrological
basis and the reference systems and frames, which
are crucial nowadays for all Earth observing systems.
GGOS is built on the IAG Services (IGS, IVS, ILRS, IDS,
IERS, IGFS, …) and the products they derive on an operational
basis for Earth monitoring making use of a large
variety of space- and ground-based geodetic techniques
such as Very Long Baseline Interferometry (VLBI),
Satellite and Lunar Laser Ranging (SLR/LLR), Global
Navigation Satellite Systems (GNSS), Doppler Orbitography
and Radiopositioning Integrated by Satellite
(DORIS), altimetry, InSAR and gravity satellite missions,
gravimetry, etc. All these observation techniques are
considered integral parts of GGOS, allowing the monitoring
of the Earth's shape and deformation (including water and
ice surfaces), the Earth's orientation and rotation and the
Earth's gravity field and its temporal variations with an
unprecedented accuracy. These quantities are direct
evidence of many global processes that have a crucial
impact on human society such as earthquakes, volcanism,
floods, sea level change, climate change, ground water
redistribution, mass balance of the polar ice sheets, etc.
At present, the document "The Global Geodetic Observing
System: Meeting the Requirements of a Global Society on
GGOS: the IAG Project
M. ROTHACHER 1
1 Markus Rothacher: GeoForschungsZentrum Potsdam (GFZ), Department 1: Geodesy & Remote Sensing, Telegrafenberg, D-14473 Potsdam,
Germany, Tel: +49-331-2881100, Fax +49-331-2881111, e-mail rothacher@gfz-potsdam.de
145
a Changing Planet in 2020" is written. It will contain the
specifications for GGOS in terms of concepts, conventions,
infrastructure and services. This document provides the
basis for the further development of GGOS over the next
decade and more.
German Activities in the Framework of GGOS
Germany is participating in the activities of GGOS in
several ways:
1. Memberships in GGOS (Steering Committee, Science
Panel, Working Groups, ...);
2. Satellite missions;
3. National Projects.
1. GGOS Memberships
Germany is very active in the GGOS organization as can
be seen from the following memberships in GGOS:
Chair of GGOS MARKUS ROTHACHER (GFZ)
Steering Committee
Members
Science Panel
Member
Working Group
Chairs
2. Satellite Missions
JOHN DOW (ESOC), HERMANN
DREWES (DGFI), CORINNA KRONER
(University of Jena), BERND RICHTER
(BKG), WOLFGANG SCHLÜTER (BKG),
TILO SCHÖNE (GFZ)
REINER RUMMEL (TU Munich)
HERMANN DREWES (DGFI), BERND
RICHTER (BKG)
Satellites play an important role in Earth observation, since
they allow a homogeneous coverage of the Earth. Germany
is leading or heavily involved in the following satellite
missions that are of importance to GGOS (launch year in
brackets, all financed):
– CHAMP (2000): Gravity field, magnetic field and
atmospheric sounding mission (GFZ, DLR, NASA);
– GRACE (2002): Gravity field mission with inter-satellite
link (NASA, GFZ, DLR);
– GOCE (2007): Gravity gradiometry mission for a
high-resolution static gravity field (ESA);
– TerraSAR-X (2007): SAR interferometry mission (DLR,
Astrium, GFZ);