Deglaciation-induced uplift along the Greenland ice margin observed with InSAR

Abstract:

The Greenland ice sheet is rapidly shrinking with the fastest retreat and thinning occurring at the ice sheet margin and near the outlet glaciers. The changes of the ice mass cause an elastic response of the bedrock. Ice mass loss during the summer months is associated with uplift, whereas ice mass increase during the winter months is associated with subsidence.

The German TerraSAR-X satellite has systematically observed selected sites along the Greenland ice sheet margin since summer 2012. Here we present ground deformation observations obtained using an InSAR time-series approach based on small baseline interferograms. The deformation data reveal the seasonal variations and net uplift. Relative variations in the seasonal amplitude for different sites along the ice sheet margin points to spatial variations in ice loss. The combination of ground deformation observations and independent observations of ice volume changes from airborne and spaceborne altimeters places constraints on the firn density of the lost ice volume.