The integration of JERS-1 and ERS SAR in differential interferometry for measurement of complex glacier motion

Abstract

Complex glacier motion in the Grove Mountains region, Antarctica, is measured using four-pass differential synthetic aperture radar (SAR) interferometry (InSAR). The components of the motion vector field are resolved using a 44 day-separation Japanese Earth Resources Satellite-1 (JERS-1) InSAR pair and a European Remote-sensing Satellite-1/-2 (ERS-1/-2) tandem InSAR pair. The 44 day temporal baseline provides the sensitivity required to observe the range of ice motion (around 8-10 ma-1), and the 1 day short baseline provides the best choice for glacier digital elevation model reconstruction. It is remarkable that the scattering field of the JERS-1 pair remained coherent over the long time interval and the interferometric fringes are clear. The overall ice flow is from east to west, downslope and towards Lambert Glacier. The regional flow is obstructed by nunataks extending north-south, with two wide gaps. Two narrow glaciers flow past the nunataks and rejoin each other at the downstream end. Regional morphology, and the resolved flow in the Grove Mountains area, suggests that ice flow is channeled throughout this eastern flank of Lambert Glacier.