Analysis of SAR Imagery During the ONR/SHOWEX Program

Unique, high-resolution and coincident in situ turbulence data, and RADARSAT-derived SAR imagery of the ocean surface were captured during the Shoaling Waves Experiment, sponsored by the Office of Naval Research (ONR). Of particular interest are two cases where the aircraft flew from what appears to be a high wind area to a region of low winds. An outstanding problem in scatterometry and SAR imagery is the determination of the minimum wind speed necessary to produce measurable radar backscatter, and how that may be effected by the air/sea temperature difference. While studied extensively in the laboratory under neutral conditions, there have been only two (and only very recent) published field reports that demonstrate that minimum wind speed, again under near neutral conditions. In this talk we present preliminary analyses of these data sets whose attempt is to better determine the minimum wind speed necessary to produce measurable radar backscatter.