Differential SAR Interferometry and Co-polar Phase Differences for Snow Water Equivalent Estimation

Abstract:
The Snow Water Equivalent (SWE) is an important parameter for hydrological and climate models. It has been shown previously that the interferometric phase between two repeat-pass SAR measurements can be related to the SWE change between those acquisitions, but this method is limited due to phase wrapping. Furthermore, it is possible to relate the Co-polar Phase Difference (CPD) between two polarimetric channels to the depth of newly accumulated snow. This study presents an approach to include the information obtained from the CPD in the Differential Interferometric Synthetic Aperture Radar (DInSAR) SWE retrieval algorithm to overcome the problem of phase wraps and improve its performance. Preliminary results show that the link between CPD and snow depth change can be used to estimate phase wraps of the interferometric phase.