Retrieval of Snow Mass using Ku- and X-band SAR Data

Abstract An overview on a method for retrieving snow mass (snow water equivalent, SWE) from dual-frequency (Ku-and X-band) backscatter data is presented. Basic principles, input data requirements, and constraints of the re-trieval algorithm are explained. During the AlpSAR campaign in winter 2012/13 Ku- and X-band radar images were acquired with the airborne SnowSAR sensor over three test sites in the Austrian Alps. Radar backscatter signatures and SWE maps, derived from SnowSAR backscatter images, are shown for the test site Leutasch, lo-cated in an Alpine valley. The impact of snow structure on radar backscatter and SWE retrieval is discussed. 1 Introduction Fresh water stored in the seasonal snow cover and in snow and ice of glaciers is a main component of the global water cycle and an important water resource.Spatially detailed data on the mass of snow (the snow water equivalent, SWE) accumulating on land surfaces and on glaciers are needed for water management, hy-drology and runoff forecasting, and for assessing im-pacts of climate warming on water supply. To date ob-servational data on SWE are obtained from in situ point measurements. The lack of spatially distributed SWE data accounts for a main gap in knowledge of the water cycle at regional to global scales. To overcome this defi-cit, the satellite mission COld REgions Hydrology High-resolution Observatory (CoReH