Accession Number : AD0660604

Title :   INFLUENCE OF PARTICLE SIZE DISTRIBUTION ON REFLECTED AND TRANSMITTED LIGHT FROM CLOUDS,

Corporate Author : SOUTHWEST CENTER FOR ADVANCED STUDIES DALLAS TEX

Personal Author(s) : Kattawar,George W. ; Plass,Gilbert N.

Report Date : 24 AUG 1967

Pagination or Media Count : 44

Abstract : The light reflected and transmitted from clouds with various drop size distributions is calculated by a Monte Carlo technique. Six different models are used for the drop size distribution: isotropic; Rayleigh; haze continental; haze maritime; cumulus; nimbostratus. The scattering function for each model is calculated from the Mie theory. In general the reflected and transmitted radiance for the isotropic and Rayleigh models tend to be similar as are those for the various haze and cloud models. The reflected radiance is less for the haze and cloud models than for the isotropic and Rayleigh models, except for an angle of incidence near the horizon when it is larger around the incident beam direction. The transmitted radiance is always much larger for the haze and cloud models near the incident direction; at distant angles it is less for small and moderate optical thicknesses and greater for large optical thicknesses (all comparisons to isotropic and Rayleigh models). The downward flux, cloud albedo, and mean optical path are discussed. The angular spread of the beam as a function of optical thickness is shown for the nimbostratus model. (Author)

Descriptors :   (*CLOUDS, OPTICAL PROPERTIES), MONTE CARLO METHOD, ATMOSPHERE MODELS, HAZE, LIGHT, REFLECTIVITY, PARTICLE SIZE, CUMULUS CLOUDS, SCATTERING, WATER VAPOR

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE