Comparison between the attenuation of the electromagnetic waves due to moist snow and dry snow

Based on the point matching technique, the attenuation of electromagnetic waves due to two types of snow are computed. The analysis is restricted to the forward scattering direction from oblate spheroidal moist and dry snow. Numerical results are obtained for two orthogonal polarizations of the incident wave. The calculations are made for various microwave frequencies, between 6 and 100 GHz, and also for different precipitation rates, between 0.5 and 3 mm/hr. The effect of the frequency and the precipitation rate on the attenuation for both types of snow is examined. It is found that at a fixed value of the precipitation rate, the attenuation of both polarizations for both types of snow increases with increasing frequency and the attenuation of dry snow is always greater than the attenuation of moist snow. The difference between the attenuations of both types increases with increasing frequencies. It is also observed that at a fixed frequency, the attenuation of both polarizations for both types of snow increases with increasing precipitation rate and the attenuation of dry snow is greater than the attenuation of moist snow. The difference between the attenuation of both types is also observed to increase with increasing precipitation rate.