Anisotropic scattering in the clouds of Venus

[摘要] Many of the past analyses of the infrared spectra for Venus have adopted an isotropically scattering, homogeneous, atmospheric model. In this work, the anisotropic scattering phase function w* (1+a*cosO) has been used to demonstrate the effects of anisotropy on observable quantities. L.D.G. Young's equivalent width data for the 782 band has been used to calculate combinations of C2 specific abundance, pressure, continuum albedo, and anisotropy. These combinations give values for the atmospheric parameters of mean free path, aerosol number density, and total optical thickness of the clouds. Approximate similarity relations are employed to determine the ;;true;; atmospheric parameters from the isotropic calculations. These extrapolated values agree well with the recent Venera probe data. The analysis indicates a total cloud optical thickness of 3 with a continuum single scattering albedo near unity. The derived aerosol number density, 45 cm^3, and mean free path, .76 km., liken the clouds of Venus to the strato-cirrus clouds of Earth.

[发布机构] Rice University