A numerical simulation of estimating snow wetness with ASAR

In hydrological investigations, modeling and forecasting of snow melt runoff requires timely information about snow properties and their spatial variability. The liquid water content in snow pack is an important parameter. A fully polarimetric C-band synthetic aperture radar (SAR) has the capability to estimate the free liquid water content-snow wetness-in the top layer of a snow pack quantitatively as demonstrated in Shi and Dozier 1995). The objective of this study is to develop an algorithm under the configuration of ASAR's C-band dual-copolarization measurements, e.g., HH and VV polarization. We have established a model-simulated C-band data-base by using multi-scattering model. The data-base covers the most possible wet snow physical properties and surface roughness conditions. Using this data-base, an inversion algorithm has been developed for using C-band dual-copolarization measurements. The newly developed algorithm mainly involved two steps: 1) decomposition of the surface and volume scattering signals, and 2) then using each scattering component to estimate snow wetness.