Analysis and Objective Identification of Regions of Enhanced Electrification via Differential Reflectivity Depolarization Streaks

Differential reflectivity depolarization streaks are caused by strong electric fields that cause low-inertia pristine ice crystals to not be perfectly aligned with its minor axis in the vertical. The ice crystal’s dipoles are excited by either the H or V polarization signals in WSR-88D data thus causing the streaking pattern. Depolarization streaks are more likely to occur in stratiform regions that can be associated with large infrequent lightning flashes. Studies have suggested that these features provide insight into regions of strong electric fields and can be used as an indicator for the potential of lightning. However, no study has quantitatively studied the use of differential reflectivity depolarization streaks to nowcast strong electrification and/or lightning. Depolarization streak characteristics will be analyzed prior to lightning initiation. This study will investigate both warm and cold season stratiform regions to demonstrate the robustness of using differential reflectivity depolarization streaks to anticipate lightning initiation and/or cessation. Overall, this study hopes to quantitatively demonstrate the viability to identify depolarization streaks and its nowcasting ability to estimate infrequent lightning flashes.