Multiparameter Radar Modeling and Observations of Melting Ice

Abstract

This paper uses a microphysically detailed graupel and hail melting model, described by Rasmussen and Heymsfield, which is coupled to a radar model that computes multiparameter variables such as differential reflectivity, linear depolarization ratio, the specific propagation differential phase shift and X-band specific attenuation. The microphysical model is initialized with two different summer-time sounding profiles (Colorado and Alabama). Sensitivity studies are performed with respect to particle shape and orientation distributions. The hail melting model is also initialized with a summertime sounding from the Munich, FRG area, and C-band differential reflectivity is computed for application to radar data from the DFVLR radar. A simple spherical hail melting model is also used to study the effects of absorption and scattering on the X-band attenuation. NCAR CP-2 radar measurements from the MIST (Microburst and Severe Thunderstorm) project and from CINDE (Convective Initiation and Downburst Experiment) are used to illustrate the usefulness of multiparameter data in studying the melting of ice in convective storms.