Interpretation of GIA and ice-sheet mass trends over Antarctica using GRACE and ICESat data as a constraint to GIA models

The Gravity Recovery and Climate Experiment (GRACE) and Ice, Cloud, and land Elevation Satellite (ICESat) have provided data sets covering observations over a period of more than 6 years since their respective launches. In this study, we used the GRACE mass change trend obtained by version 2 of CNES/GRGS solutions and the ICEsat elevation change trend from October 4, 2003, to March 21, 2008, to assess whether currently used glacial isostatic adjustment (GIA) models agree with the data sets. For six selected areas over West Antarctica, the mass trends for the surface ice sheet, which were obtained by subtracting the four GIA model trends (ICE-5G, IJ05, ANT5 and ANT6) from the estimated GRACE mass trend, were compared with the ICESat trends in order to assess whether these two trends are consistent within the uncertainty of the ice column density. The results show that the mass trend predicted by IJ05 GIA model is the most preferable to explain surface mass trends over some of these areas. The result is consistent with Riva et al. (2009); their estimated GIA trend from GRACE and ICESat data is very similar with IJ05 model.

Research Highlights
► Antarctic mass and elevation change trend were estimated from GRACE and ICESat data.
► The surface ice sheet mass trend was estimated using GRACE and GIA-model trends.
► We compared the trend with the ICESat trend, and assess whether they were consistent.
► IJ05 GIA model is the most preferable to explain some mass trends in West Antarctica.