Multiparameter Radar Measurements in Colorado Convective Storms. Part I: Graupel Melting Studies

Abstract

This paper presents an analysis of coordinated measurements taken by the NCAR CP-2 radar and the Wyoming King Air aircraft flown by NCAR during the May Polarization Experiment, which was held new Boulder, Colorado. A key feature of this paper is the rigorous computation Of ZH, ZDR and LDR using an electromagnetic model that is coupled to a detailed one-dimensional microphysical model of melting graupel. The graupel melting model was initialized with aircraft-measured graupel spectrum and sounding data. Two case studies during MAYPOLE '83 were considered where model-derived vertical profiles of ZH and ZDR were computed and compared to radar measurements, resulting in excellent agreement. The RHI profiles of ZH, ZDR and LDR through the core of an isolated convective storm revealed new and interesting microphysical data which are consistent with model computations. The radar measurements and model results of this paper show that a significant breakthrough has been made in the radar remote sensing of storm microphysics.