OBSERVATIONS OF ICE-SHEET MOTION IN GREENLAND USING SATELLITE RADAR INTERFEROMETRY

We present interferometric observations of ice-sheet motion in western Greenland based on pairs of ERS-1 synthetic aperture radar (SAR) imag es. These observations provide the first detailed regional view of ice motion associated with dynamically supported topography near the marg in of an ice sheet. The interferograms of this area are much more comp licated than other interferograms of ice sheets presented to date. We devote the largest part of this paper to explaining the source of the complexity in these interferograms. A synthetic interferogram based on a simple model helps to illustrate the effects of different component s of the ice velocity held in interferometric data and suggests a meth od for estimating the large-scale ice velocity field from such data.