Horizontal Ice Velocity Estimation and Grounding Zone Detection in the Surroundings of Schirmacheroase, Antarctica, Using SAR Interferometry

Abstract

Repeat-pass synthetic aperture radar (SAR) interferometry is utilized to estimate the ice velocity field and to locate the grounding line between grounded ice and floating ice shelf in the surroundings of the Schirmacheroase (71S, l2E).Because the interferometric phase is sensitive only to one component of the displacement vector ascending and descending passes are combined to derive the horizontal ice velocity field of the inland ice.By analysing this two-dimensional flow field the shape of the main ice stream in the vicinity of the Schirmacheroase is obtained.Amigration of the grounding line of about 4.5 km is discovered where the main ice stream begins to float.This migration is very probably caused by ocean tides.To assess the accuracy of the interferometry results ground truth data are used.Zusammenfassung: Die "Synthetic Aperture Radar" (SAR)-Interferometrie wird zur Bestimmung des Geschwindigkeitsfeldes von Eis und zur Lokalisierung der Aufsetzlinie zwischen gegrundetem Eis und schwimmendem Schelfeis in der Umgebung der Schirmacheroase (71 oS, 120) angewandt.Da die interferometrische Phase nur Informationen ber eine Komponente des Verschiebungsvektors beinhaltet, werden fr den Bereich des Inlandeises aufsteigende und absteigende Orbits zur Ableitung des horizontalen Geschwindigkeitsfeldes kombiniert.