Study On The Radiative Transmission And Scattering Properties Of Cirrus Clouds

The radiative transmission and scattering properties of cirrus clouds and ice crystals are mainly discussed in this thesis. Using the theory of Van de Hulst approximation theory and the polynomial approximation method, the ice particle single-scattering calculation of the parameters are given. Assuming ice crystals size distribution of cirrus clouds according to Gamma distribution, based on the database of single-scattering properties for each of ice crystal particle computed by Yang et al. and the range of the effective size of ice crystle particles for midlatitude cirrus clouds gave by Jeffrey R. Key et al., the mean single-scattering properties of cirrus clouds are numerical studied. The variation of mean absorption efficiency,extinction efficiency, single-scattering albedo, asymmetry factor and phase function of cirrus clouds as a function of effective size and wave-length are analyzed in detail. The solar irradiance, transmittance and the impact of cirrus clouds on the background radiation in the case of cirrus and cloud-free are calculated separately by using Modtran, which preliminary analysis of the transmission characteristics of cirrus clouds. Finally based on the experiments and Radar Measurement System, the Fernald integration method is applied to compile the software which can process and analysis the data of atmospheric laser radar.