Climate-driven deformation of the solid Earth from GRACE and GPS
Article first published online: 22 DEC 2004
Copyright 2004 by the American Geophysical Union.
Geophysical Research Letters
Volume 31, Issue 24, December 2004
How to Cite
2004), Climate-driven deformation of the solid Earth from GRACE and GPS, Geophys. Res. Lett., 31, L24605, doi:10.1029/2004GL021435., , , and (
- Issue published online: 22 DEC 2004
- Article first published online: 22 DEC 2004
- Manuscript Accepted: 29 OCT 2004
- Manuscript Revised: 21 OCT 2004
- Manuscript Received: 7 SEP 2004
 GRACE data indicate large seasonal variations in gravity that are assumed to be related to climate-driven fluxes of surface water. Seasonal redistribution of surface mass should deform the Earth, and our calculations using GRACE data suggest vertical deformations of ∼13 mm in the region of greatest flux, the Amazon River Basin. To test the GRACE gravity-hydrology connection, we analyzed GPS data acquired from sites in this region. After accounting for degree 1 variations not observable with GRACE, we find that annual deformation measured with GPS correlates highly with predictions calculated from GRACE measurements. These results confirm the variations in surface water sensed by GRACE, which are significantly larger than those predicted by some hydrology models. The results also demonstrate that GRACE can be an important tool for monitoring deformation of the Earth, and suggest that combined analysis of GRACE and GPS may be a useful approach for estimation of geocenter variations.