Snow mapping with active microwave sensors

Abstract

Hydrological interest in mapping snow concentrates on the phase of snow depletion when at least part of the snow cover is wet. In this situation, snow has a very low backscatter coefficient, smaller than almost any land surface at X-band. Together with the independence of cloud cover and time, this unique signature of snow enables frequent and regular mapping of snow even in rugged terrain. First results from a synthetic aperture radar experiment made during the melting season—even under unfavourable conditions—clearly indicate this potential.

The backscatter data used in this work are based on four seasons of scatterometer-measurements made on the alpine test site Weissfluhjoch, Davos, and on a comparison with additional backscatter data from groups in Europe and the U.S.A