Improved Radiative Transfer Calculations from Information Provided by Bulk Microphysical Schemes

Abstract

Abstract Bulk microphysical schemes are providing increasingly detailed information of hydrometeor profiles both within and below clouds. This information can be used to improve radiative transfer calculations with little increase in computation time. In the simple context of a single column, the work described in this paper uses a relatively complex radiation code and a five-category bulk microphysical scheme to investigate simple and computationally efficient methods of utilizing microphysical information in radiative transfer calculations. The bulk microphysical scheme used here is typical of many and predicts mixing ratios of liquid water droplets, rain, ice crystals, snow, and graupel. When all hydrometeors are treated separately in the radiation scheme, improvements can be made to the radiative transfer calculations. First, the effective radii of the various hydrometeors can be calculated from information provided by the microphysical scheme. Also, adjustments can be made to the radiation scheme to ...