Melting and Shedding of Graupel and Hail. Part I: Model Physics

Abstract

A sensitivity study on the melting and shedding behavior of individual graupel and hail is presented utilizing the detailed microphysical model presented in Part I. The influence of particle density and size, atmospheric temperature profile, relative humidity profile, liquid water content, shedding parameterization, and heat transfer rates are investigated. The results show that the melting of graupel and the melting and shedding behavior of hailstones are significantly affected by the initial particle density and size, temperature profile, and relative humidity. When graupel and hail are grown in a Doppler-derived three-dimensional wind field, the results show that the melting and shedding behavior of the graupel and hail are relatively insensitive to changes as large as 25% in the heat transfer coefficient or to the differences between the Rasmussen et al. and the Chong and Chen shedding parameterizations.