9315251 Liou The objective of this research is the development of light scattering programs for nonspherical ice crystals using both the theoretical and experimental approaches. The proposed theoretical studies include the application of the newly developed geometric ray-tracing/Monte Carlo method applied to complex ice crystals such as capped columns, spatial aggregates, and graupel. For ice crystals with size parameters less than about 30, we propose to develop a numerical technique, referred to as the finite difference time domain method, for the solution of the scattered field. The proposed laboratory experiment uses a laser light-scattering analog measurement for a single crystal. Initial experimental arrangements and preliminary results are presented and the proposed experiments for the measurements of the phase matrix elements for crystals of various shapes and sizes are outlined. ***