Evaluation of GPM DPR Surface Precipitation Type Identification, Using Ground-Based Polarimetric WSR-88D Radar and mPING Crowdsourcing Observations

Abstract:

In this study, the accuracy of surface precipitation types derived from the Global Precipitation Measurement (GPM) core satellite Dual-Frequency Precipitation Radar (DPR) is evaluated using ground-based polarimetric Weather Surveillance Radar-1988 Doppler (WSR-88D) S-band analyses and surface precipitation type reports from Meteorological Phenomena Identification Near the Ground (mPING) crowdsourcing data. Several cold-season precipitation events are investigated to determine the consistency between the surface precipitation types obtained from these three datasets. Dual-polarization radar data provide valuable information on precipitation type and location of transitions from liquid to frozen precipitation, with detail undetectable in conventional radar reflectivity data alone. For efficiency in processing and analyzing the WSR-88D data, a quasi-vertical profile (QVP) methodology is implemented to examine the temporal evolution of ice microphysical processes throughout the depth of the cloud. The mPING data are used to validate the radar analyses, specifically in cases of ground-based radar-indicated transitions in precipitation type at the surface. Synthesis of these datasets will help to evaluate the performance of GPM DPR precipitation measurements and improve the use of the satellite system in the future.