Wind speed estimation in the Tyrrhenian Sea by means of X-band COSMO-SkyMed SAR data

In this paper, the SAR-based wind speed estimation at sea is investigated over X-band COSMO-SkyMed© SAR data in the test area of Tyrrhenian Sea basin. The SAR data set consists of X-band VV-polarized Level 1B Detected Ground Multi-look (DGM) StripMap HImage and ScanSAR Huge Region COSMO-SkyMed© SAR measurements, collected in the test area on 2009 and 2010, respectively. The sea surface wind speed estimation is accomplished by means of the SAR wind speed algorithm based on the Azimuth cut-off procedure, which is properly extended to the non trivial X-band case and therefore calibrated over both StripMap HImage and ScanSAR Huge Region modes SAR data. The reference wind speed, which is used as ground truth for both calibration and SAR-based wind speed estimation purposes, is provided by timely and spatially co-located 25km × 25km QuikSCAT and 12.5km × 12.5km ASCAT scatterometer wind speed for the StripMap HImage and ScanSAR Huge Region SAR data sets, respectively. Experimental results demonstrate the effectiveness of the proposed approach for sea surface wind speed estimation purposes, taking full benefits of X-band COSMO-SkyMed© SAR data.