LIGHT SCATTERING IN SPHERICAL ATMOSPHERES

Abstract

The scattered radiation fields in spherical planetary atmospheres have been considered by a new method which is called the Quasi-Spherical method. This method is applicable to planets with radii which are much larger than the height of their atmosheres. The scattering of 0.5 (mu)m radiation in a conservative and vertically inhomogeneous atmosphere has been discussed. Results comparing the emerging radiation from plane-parallel and spherical models for the earth's atmosphere have been presented for four different aerosol distributions in addition to the normal molecular composition. These results indicate measurable differences on the order of 10 to 300% as the angle of observation and/or the angle of incident sun falls within 10(DEGREES) from the horizon. Also, the obtained results in the spherical atmosphere show that additional layers of aerosols in either the stratosphere or the troposphere can be detected by satellite or aircraft radiometric measurements, while the plane-parallel atmosphere does not permit such a detection. The accuracy of the obtained results by the present method can be increased by increasing the number of spherical shells in the spherical atmosphere. The emerging radiation in homogeneous and inhomogeneous Rayleigh atmospheres as computed by the Quasi-Spherical and the Monte Carlo methods compare quite well. By applying the divergence theorem it was shown by the present method that the total flux in the spherical atmosphere is conserved within 1.351%.