MILLIMETER-WAVE RADAR SCATTERING FROM SNOW .2. COMPARISON OF THEORY WITH EXPERIMENTAL-OBSERVATIONS

Using a truck-mounted platform, backscatter measurements were made at 35, 95, and 140 GHz for a variety of snow conditions to evaluate the radar response to incidence angle, surface roughness, and liquid water content. Good agreement was obtained between the experimental observations and theoretical calculations based on the numerical solution of the radiative transfer equation presented in the preceding paper. A notable exception is when the snowpack is in the refreezing phase of the diurnal cycle, during which the snowpack is characterized by a dry surface boundary with wet layers underneath. To accommodate this type of condition, a hybrid first-order numerical solution is proposed. The hybrid approach provides excellent agreement between theory and experiment.