Light scattering by non-spherical particulates in the planetary atmosphere.

点击翻译按钮获取中文摘要

On the light scattering by the spherical particulates in the planetary atmosphere, there is an explicit solution called Mie theory. However, there is no standard theory for the light scattering by the non-spherical particulates. In this research, we intended to study the effects of the light scattering by the non-sphericsl particulates in the atmosphere using an approximate method instead of seeking the explicit solution.To do this research, we had the following three stages; (1) We collected the experimental data for the light scattering by the non-spherical particu1ates, such as the laboratory experiments on the scattering by artificial water ice clouds by Sassen and Liou (1979). Then, we obtained the scattering phase functions using a semi-empirical theory developed by Pollack and Cuzzi (1980). (2) Next, we have developed a new discrete-ordinate algorithm for the radiatve transfer equation, which can be applied to the non-homogeneous planetary atinosphere. (3) Using the above phase functions and algorithm, we have constructed a system to estimate the optical thickness of the Martian white clouds based on the earth-based photographic observations. The optical thickness of the Olympus cloud, Hellas cloud and Tharsis morning cloud are about 0.5, 1.0, and 2.5-3.0, respectively. We have plans to investigate the atmospheric thermal structures of the other planets allowing for the thermal effects of the non-spherical particulates such as, the ice clouds and dust particles in the atmosphere.