Hail characterization via the joint utilization of reflectivity, differential reflectivity, and linear depolarization ratio data

It is well known that dual polarization radars can differentiate between raindrops and hailstones by exploiting the fundamental differences in their mean shapes and orientations. In particular, Aydin et. al. defined a boundary in S-Band horizontal reflectivity (Zh), differential reflectivity (Zdr) space that distinguished hail from rain. They related the identification of hail to the magnitude of the deviation from this rain / hail boundary through a parameter that they called Hail Differential Reflectivity (HDR). In the present study, HDR data are combined with Linear Depolarization Ratio (LDR) measurements in an effort to develop a hail severity index. Hail severity index maps based on polarimetric data collected by the CSU-CHILL radar will be presented and related to verification data from surface observations of hail.