ABSTRACT
In this study, we evaluate the two years (from 1 May 2019 to 30 April 2021) global operational sea surface wind speed (SWS) product of Fengyun-3D (FY-3D) polar-orbit meteorological satellite microwave radiation imager (MWRI) using ERA-5 reanalysis data. The total mean bias error (MBE), mean absolute error (MAE) and correlation coefficient of FY-3D/MWRI SWS product are −0.432 ± 3.09 m/s, 1.896 ± 2.50 m/s and 0.76, respectively. The current FY-3D/MWRI SWS data are comparable with the wind speed data of ERA-5 at most of the sea areas, especially the farther offshore sea areas. However, we still find significant overestimations (more than 5 m/s) near the coasts and typical differences in horizontal MBE values in different ascending and descending orbits. Besides, the rainy pixels as another negative impact factor are also common in FY-3D/MWRI SWS product, which can induce manifest overestimations of SWS. Therefore, the future FY-3/MWRI SWS operational algorithm should further develop a rigorous and robust quality-control module and a joint rainy pixel identification algorithm to better eliminate the unreasonable (or anomalous) pixels and rainy pixels. Moreover, the detailed evaluation on the on-orbit calibration performance of MWRI sensor is also necessary for both ascending and descending orbits.
Acknowledgements
The authors would like to thank the ECMWF for freely providing their ERA-5 reanalysis data (https://cds.climate.copernicus.eu/cdsapp#!/home) firstly. Moreover, FY-3D/MWRI SWS data are freely downloaded from NSMC/CMA website of http://satellite.nsmc.org.cn/portalsite/default.aspx. Besides, we are particularly grateful to Dr. Fangli Dou from National Satellite Meteorological Center of CMA for her discussions on this work. This work was supported by the Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) (No. SML2021SP102). We also thank the editor and anonymous reviewers for their thoughtful suggestions and comments.
Disclosure statement
No potential conflict of interest was reported by the author(s).