Cross Characterization of Alpine Snow Packs Using a Portable 3-D HR Imaging System, C-Band Spaceborne SAR Observations, In-Situ Measurements and a Physically Based Snow Evolution Model

This paper proposes to use ground-based high-resolution 3-D radar imaging, in order to study the interaction between electromagnetic waves and snow packs, and to provide a physical interpretation for the reflectivity of Sentinel 1 images over snow covered regions. Preliminary results show that, according to usually assumed behaviors, fresh snow has an extremely low reflectivity at C band, and wet snow does not let waves go through. Between these two extreme configurations, this study reveals that snow packs may have complex and significant scattering patterns, mainly due to the presence of transformed snow and of rough interfaces between the layers, again due to transformation phenomena.