Reflectance of snow at millimeter wavelengths

Radar cross sections of ground snow were calculated for linearly polarized incident radiation at 8.6, 17, 35, and 95 GHz. The snow was modeled as a plane parallel medium consisting of ice grains mixed with varying amounts of liquid water. Individual ice grains were treated as independent Rayleigh scattering centers and the water as a homogeneous absorbing medium. Calculations of the radar cross section were made using known solutions of the radiative transfer equation. These were then compared with experimental data. Curves are given which can be used to find the radar cross section given the grain size and the water content of the snow.