Absorption and Scattering Properties of Surface Melted Ice Sphere in Visible and Near Infrared Regions
冰—水球形粒子在太阳短波段的吸收与衰减

Based on the Mie theory and the theory by Aden and Kerker;; the absorption and scat-tering cross-sections of concentric spherical water and ice particles are computed in the solar radiationspectrum ranging from 0.3-to 4.0um of wavelength. The results show that because both the real andimaginary parts of refractive indices for water and ice are quite close in visible and near infrared bands;;there are little differences in the absorption and scattering properties between pure water;; pure icespheres and coneentric water-ice (ice-water) spheres. It is therefore unlikely to explain the phenomenonof cloud absorption anomaly simply by the surface melted ice particles which cause the bright bandsnear 0oC isotherm in stratiform clouds as seen in microwave radar observations. However;; ice particlesincluding water-ice crystals have to be taken into account in calculating the absorptivity of solar radia-tion by mixed-phase clouds since the absorption cross-section increases quickly with increasing particlesize and the effective radius of ice crystals are much larger than those of liquid water droplets.