Retrieval of Sea Surface Wind Speeds from Gaofen-3 Full Polarimetric Data

• DOI: 10.20944/preprints201902.0185.v1
• Publication Date: 2019-02-27T05:03:31Z
• Authors: Tianyu Zhang; Xiao-Ming Li; Qian Feng; Yongzheng Ren; Yingni Shi
• Keywords: Root mean square; Typhoon

In this paper, sea surface wind speed (SSWS) retrieval from Gaofen-3 (GF-3) quad-polarization stripmap (QPS) data in vertical-vertical (VV), horizontal-horizontal (HH) and vertical-horizontal (VH) polarizations is investigated detail based on 3,170 scenes acquired October 2016 to May 2018. The radiometric calibration factor of the VV polarization examined first. This generally meets requirement SSWS accuracy with an absolute bias less than 0.5 m/s but shows highly dispersed characteristics. These results lead retrievals a small 0.18 rather high root mean square error (RMSE) 2.36 compared ERA-Interim reanalysis model data. Two refitted ratio (PR) models for QPS HH are presented. Based combination incidence angle- azimuth angle-dependent PR CMOD5.N, derived 0.07 RMSE 2.26 relative speed. A linear function relating normalized radar cross section (NRCS) VH derived. retrieved show good agreement WindSat data, 0.1 2.02 m/s. We also apply GF-3 Wide ScanSAR typhoon SOULIK, which surprisingly yields very results. comparison among three different datasets current study our previous work demonstrate that general has 0.3 2.0 ±0.2 various datasets. Further improvement will depend dedicated efforts.