Radiative parameterization for the FNWC global primitive equation model.

Abstract

This study was an evaluation of a radiational scheme for inclusion in a numerical weather prediction model. This scheme uses empirical formulations for atmospheric absorptivities , scattering and reflectivity and cloud and earth surface reflectivity to compute the solar insolation received and absorbed by the earth and key atmospheric layers. Longwave cooling by the earth is also treated with empirically derived emissivities for watervapor and carbon dioxide. This radiation model includes a two-layer cloud parameterization scheme and calculates the effect of an additional cloud layer on previous studies . In testing the validity of this model, use was made of Fleet Numerical Weather Central data in the form of vertical soundings on a spring day over the ocean. This data was used to calculate the radiation balance at the tropopause, the earth's surface and the key layers of the atmosphere.