Radiative Transfer in Water Clouds in the Infrared Region

Abstract

The problem of diffuse reflection, transmission and emission of infrared radiation by water clouds is investigated in the wavelength region from 5?50 ?. The drop-size distribution of clouds is assumed to be that of altostratus measured by Diem. The phase function and other optical properties of the clouds are estimated from the value of the refractive index of water proposed by Pontier and Dechambenoy. Radiative processes due to both cloud droplets and water vapor in the cloud are taken into account, and a method of averaging the solution over a spectral interval including a number of absorption lines is developed.