The Earth gravity field including its temporal variations is a key parameter for understanding the system Earth. Dedicated gravity satellite missions such as GFZ-1, CHAMP, GRACE, GOCE and GRACE-FO, to a large extent developed, operated and analysed by Section 1.2, enable to study mass distribution and mass transport on various spatial and temporal scales. In this context we also make use of various LEO (Low Earth Orbiting) and geodetic SLR (Satellite Laser Ranging) satellites to estimate dynamic parameters such as the long-wavelength part of the gravity field, Earth orientation parameters, and global ground station coordinates based on a huge suite of space-geodetic tracking techniques such as DORIS, GNSS and SLR.
Consistent analyses and modelling of all existing space-borne gravity sensors and space geodetic techniques as well as simulation studies for future gravity mission concepts or the International Terrestrial Reference Frame in view of GGOS are integratively performed with our inhouse software package EPOS (Earth Parameter and Orbit System) which is conform to the most recent international standards. This allows us to support the international IAG services ILRS (International Laser Ranging Service) and IDS (International Doris Service) by operating an Analysis Center and an Associate Analysis Center, respectively.
For tracking, data reception and health monitoring of Earth observation satellites we operate the SLR station in Potsdam (as contribution to the ILRS) and a Satellite Receiving Station in Ny-Ålesund (Spitsbergen).
In support of our satellite missions we supplement our Earth monitoring on ground by superconducting gravimeters as well as by gravimetry on moving platforms (i.e. aircrafts and ships). Additionally, we make use of historial and current altimetry mission data to study global and regional sea level trends and variability. For this, we operate and analyse a network of coastal tide gauges and GPS-buys on inland lakes (e.g. Issyk Kul, Kirgistan) to validate altimetry data and to monitor sea level change to estimate potential threats for human population in coastal regions.
We design, implement and operate early warning systems, e.g. in Indonesia or Oman, to contribute to global and local hazard monitoring and we contribute to the establishment and operation of a hydro-meteorological and geodetic monitoring network and the Global Change Observatory of GFZ in Central Asia.
The various projects in our section are divided into four major topics:
- Development, operation and analysis of gravity field satellite missions
- Terrestrial and Airborne Gravimetry
- Earth System Parameters and Orbit Dynamics
- Geodetic Hazard Monitoring
The topics 1 and 3 are primarily and in close cooperation with the German Aerospace Center (DLR) executed at GFZ´s Branch Office in Oberpfaffenhofen.
Details and dedicated projects can be found in the corresponding topic pages.