HWIND Analysis Used to Validate SAR Imagery-Derived Wind Field in High-Wind Speed Conditions During Hurricane Patricia

RADARSAT-2, funded by the Canadian Space Agency (CSA) and owned/operated by MacDonald, Dettwiler and Associates Ltd. (MDA), is a commercial radar satellite carrying a synthetic aperture radar (SAR) instrument.  Scientists from the Bedford Institute of Oceanography have been developing an empirically-derived linear geophysical model function (GMF) to retrieve wind speeds from SAR imagery in high-wind speed conditions.  A RADARSAT-2 SAR image was captured while Hurricane Patricia (2015) was at near-peak intensity, which provided a unique opportunity to assess the performance of the GMF at very high wind speeds that had not previously been sampled by the instrument.  An HWIND analysis is performed for Hurricane Patricia to validate the retrieved wind speeds.  The HWIND analysis is constructed to represent Hurricane Patricia’s wind field at the same time as the RADARSAT-2 SAR image using NOAA and AFRC flight-level wind measurements reduced to the surface, processed stepped-frequency microwave radiometer (SFMR) measurements, GPS dropsonde measurements, tail-doppler radar data reduced to the surface, ASCAT measurements, RapidScat measurements, and surface station measurements.  The HWIND analysis is compared to the SAR-derived wind field image.