Mass redistribution and climate change

Simultaneously operating gravity, altimetry, and navigation satellites equipped with novel, extremely precise sensors allow for the first time to quantify how much mass is redistributed in the Earth system by observing the effect of mass transport on the Earth's gravity field and on the geometry of the land, sea, and ice surfaces. This is fundamental to the understanding of mass transport processes and interactions between atmosphere, hydrosphere, cryosphere, biosphere, land surfaces, and solid Earth, and essential for our understanding and prediction of the global water cycle and climate change.

Exploitation of satellite gravity and satellite altimetry missions to quantify mass transport and mass distribution in the Earth's system (from Rummel 2007).

 

The research aims at a quantification of mass redistribution in the Earth system. The main emphasis is on temporal mass variations in continental water storage and ice sheets using data of the CHAMP, GRACE, and GOCE satellite gravtiy missions and the ICESat and CRYOSAT-2 satellite altimetry missions. Research activities comprise 1) the development of data combination strategies for the joint inversion of simultaneous and complementary, geometric and physical observations from a multiple of geo-scientific and environmental near-Earth orbiting satellites; 2) the quality assessment of the derived mass variation estimates; 3) the calibration of global and regional hydrological models at river basin scale by closing the water balance; 4) the quantification of mass variability in Antarctica and Greenland, in particular related to the ice mass balance. The research is executetd in close cooperation with geophysicists, geologists, and hydrologists from TU Delft, and oceanographers and glaciologists from Utrecht University.

Loss of ice mass over Antarctica between 2003 and 2006 from GRACE (left) and ice surface elevation change over the same period from ICESat (right).

A 3-year time series of water storage variations within the Zambezi river basin as inferred from GRACE KBR data. The right panel shows a comparison with the regional hydrological model LEW developed at TU Delft, faculty of civil engineering.