A Parameterization for the Absorption of Solar Radiation in the Earth's Atmosphere

TLDR

Solar radiation absorption modeling is essential for atmospheric circulation models, and this parameterization is incorporated in current GISS models. The study presents a rapid method to compute solar energy absorption at the surface and atmosphere by altitude. The method uses a parametric model derived from accurate multiple‑scattering calculations, with coefficients that vary with cloud type, humidity, solar zenith angle, surface albedo, and stratospheric ozone distribution.

Abstract

A method is described for rapidly computing the amount of solar energy absorbed at the earth's surface and in the atmosphere as a function of altitude. The method is a parametric treatment, but the form of the solution and the coefficients involved are based on accurate multiple-scattering computations. In this treatment the absorption varies with the amount and type of clouds, the humidity, the zenith angle of the sun, and the albedo of the earth's surface. Within the stratosphere the absorption also depends on the vertical distribution of ozone. This parameterization for solar radiation is being used in current versions of the global atmospheric circulation model developed at the Goddard Institute for Space Studies.