Simulation of the Extinction Properties of Realistically Shaped Precipitation Particles

1. ABSTRACT INTRODUCTION Passive and active microwave remote sensing of cold-cloud precipitation requires accurate knowledge of not only the physical state of the scene being observed, but also the relationship between that physical state and the radiation being observed. However, for ice-phase precipitation and cloud particles, this relationship remains poorly understood due primarily to a lack of direct and in-situ measurements of these relationships. A major complicating factor in remote sensing of these clouds is that it is generally impossible to know the true particle shapes, sizes, and their distributions within the scene being observed. This raises two questions: (1) Is it necessary, from a remote sensing perspective, to know the exact shapes and sizes of every particle in a precipitating ice-phase cloud? (2) If not, what parameterizations or assumptions will provide the desired relationships while providing retrievals with the desired accuracy?