The Earth’s gravity field and its temporal variations are intrinsically linked to the distribution and redistribution of mass within the Earth system. Accurate knowledge of the global gravity field, primarily derived from satellite observations, is essential for modelling geodynamic processes in the oceans and solid Earth, quantifying mass transport and redistribution within the Earth system, calculating the global geoid (the reference surface for physical heights) and determining the precise orbits of satellites for positioning, navigation and Earth observation missions. The geoid is also a critical reference for studying sea-level change, modelling ocean circulation and monitoring the state and variability of the hydrosphere, including the mass balance of ice sheets and glaciers, and the global water cycle. Observations of the gravity field also enable the detection of mass-density anomalies within the Earth’s crust and mantle, providing valuable insights into the structure and dynamics of the Earth’s interior. Furthermore, gravity field products contribute to identifying major tectonic features and investigating subsurface geological and geodynamic processes. The following geodetic products are key to realising, monitoring and applying this Essential Geodetic Variable:
IAG as part of the IUGG
IAG Related Organisations
IAG collaborates closely with numerous organizations within geodesy and beyond. See the list for details.
This website is provided by the IAG Secretariat and the GGOS Coordinating Office, which are hosted by the BEV – Federal Office of Metrology and Surveying (Bundesamt für Eich- und Vermessungswesen) in Vienna, Austria.