Retrieval of Firn Thickness by Means of Polarisation Phase Differences in L-Band SAR Data ...

• Main Authors: Parrella, Giuseppe, Hajnsek, Irena, Papathanassiou, Konstantinos P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2021
• Subjects: Synthetic Aperture Radar; polarimetry; differential propagation; firn anisotropy; Greenland; glacier
• Online Access: https://dx.doi.org/10.3929/ethz-b-000515496; http://hdl.handle.net/20.500.11850/515496

The knowledge of glacier zones’ extent and their temporal variations is fundamental for the retrieval of surface mass balance of glaciers and ice sheets. In this context, a key parameter is the firn line (FL), the lower boundary of the percolation zone, whose location is an indicator of time-integrated mass balance changes. Several approaches have been developed in the last decades to map the FL by means of Synthetic Aperture Radar (SAR) imagery, mainly exploiting backscatter intensities and their seasonal variation. In this paper, an alternative approach is proposed, based on co-polarisation phase differences (CPDs). In particular, CPDs are interpreted as the result of propagation through anisotropic firn layers and are, therefore, proposed as an indicator of the presence of firn. A model is employed to demonstrate the link between CPDs and firn depth, indicating the potential of polarimetric SAR to improve firn characterization beyond spatial extent and FL detection. The proposed approach is demonstrated ... : Remote Sensing, 13 (21) ...