3D Wind Field Retrieval Applied to Snow Events Using Doppler Radar

Abstract The variational analysis method of Laroche and Zawadzki for the retrieval of the 3D wind field from single–Doppler radar data is adapted to analyze stratiform snow events. Modifications include prefiltering of noisy radial velocity data using a velocity azimuth display (VAD) analysis, the use of snow particle fall speeds derived from extended VAD analyses, and the usage of high-elevation angle data. Arctic cases were collected during the Beaufort and Arctic Storms Experiment with X-band radars located at Inuvik and Tuktoyaktuk, Northwest Territories, Canada. These were compared with C-band radar data acquired by the King City Doppler radar in southern Ontario, Canada, a midlatitude site. Retrieved vertical airspeeds were verified using data from a research aircraft. Mean horizontal speeds were verified using VAD analyses, and horizontal wind speed anomalies were checked using Mesonet station data and VAD residual analyses. The results indicate that retrieved vertical velocities are in relative ag...