Radar ice motion interferometry

We have used tandem pairs of ERS-1/2 radar observations of the Jakobshavn Glacier, in Greenland, for the purpose of estimating the ice motion. Interferograms are made from two such pairs, separated by the 35 day repeat cycle. Motion can be estimated from these without knowledge of the local topography. Although the temporal baseline of the interferograms was only one day, the correlation from the fast moving ice was very low. Because of the resulting phase noise, we have used a scene-dependent filter to help unwrap the interferograms. For the upper part of the glacier, the filter worked well. The filter and the measured ice motion are presented below.