Long-wavelength Pol-InSAR for glacier ice extinction estimation

Abstract

In recent years there has been increased interest in using synthetic aperture radar (SAR) to study and monitor glaciers for climate change research. This paper describes the estimation of ice extinctions through modelling of Pol-InSAR (polarimetric interferometric SAR) coherences as a combination of a surface contribution (from the snow-firn interface and wind-induced features) and a volume response. Ground-to-volume scattering ratios derived from a novel polarimetric decomposition are used in conjunction with Pol-InSAR interferometric coherence magnitudes to invert the extinction of the ice layer. The inversion is performed with experimental airborne Pol-InSAR data at L- and P-band collected using DLR's E-SAR system over the Austfonna ice cap in Svalbard, Norway as part of the 2007 ICESAR campaign. Extinction-dependencies on frequency and glacier zone are investigated, and validation is performed comparing P-band sounder data to inverted extinction values.