Parameterization for Longwave Scattering of Ice Cloud for Use in Atmospheric Model

摘要

A parameterization for the scattering of longwave radiation by ice clouds have been developed based on spectral property calculations with shapes and sizes of ice crystal. For this parameterization, the size distribution data by Fu and Michell and Arnott are used. And the considered shapes of ice crystal are plate,solid column,hollow column,bullet-rosette,droxtal, aggregate, and spheroid. The properties of longwave scattering by ice crystal are presented as a function of the extinction coefficient,single-scattering albedo, and asymmetry factor. The heating rate and flux by radiative parameterization model are calculated for wide range of ice crystal size,shape, and optical thickness, the their calculation results are compared with the results by using a six-stream discrete ordinate scattering algorithm.