Studies on Light Scattering and Absorption Properties of Ice Clouds for Visible and Infrared Laser Wavelengths

摘要

This letter report summarizes the results of experimental evaluations of angular scattering and absorption by ice particles of C02 laser radiation at 10.6 micrometers wavelength. Experimental results are presented which summarize particle effects such as spontaneous fragmentation and changes in the growth habit. These are compared to model predictions to determine effects upon the backscattered radiation, and polarization. A scattering model is presented which involves complete polarization information for arbitrarily oriented hexagonal columns and plates. It is discussed that a computational technique was developed for randomly oriented hexagonal cylinders and spheroids which show general agreement for phase functions of these geometric sizes and shapes except for the twenty-two and forty-six degree halo features and the backscattering maximum. An attachment to the letter report presents graphed and tabulated data for phase matrix elements for laser wavelengths of .55, .6328, .7, 1.3, 3.8 and 10.6 micrometers based on model calculations. (Author)