{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,25]],"date-time":"2026-01-25T13:49:09Z","timestamp":1769348949556,"version":"3.49.0"},"reference-count":46,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,22]],"date-time":"2024-08-22T00:00:00Z","timestamp":1724284800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2022YFC3103101"],"award-info":[{"award-number":["2022YFC3103101"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2023CFO009"],"award-info":[{"award-number":["2023CFO009"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["311021004"],"award-info":[{"award-number":["311021004"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["311021001"],"award-info":[{"award-number":["311021001"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Project of Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources","award":["2022YFC3103101"],"award-info":[{"award-number":["2022YFC3103101"]}]},{"name":"Project of Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources","award":["2023CFO009"],"award-info":[{"award-number":["2023CFO009"]}]},{"name":"Project of Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources","award":["311021004"],"award-info":[{"award-number":["311021004"]}]},{"name":"Project of Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources","award":["311021001"],"award-info":[{"award-number":["311021001"]}]},{"name":"Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)","award":["2022YFC3103101"],"award-info":[{"award-number":["2022YFC3103101"]}]},{"name":"Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)","award":["2023CFO009"],"award-info":[{"award-number":["2023CFO009"]}]},{"name":"Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)","award":["311021004"],"award-info":[{"award-number":["311021004"]}]},{"name":"Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)","award":["311021001"],"award-info":[{"award-number":["311021001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In this study, wind speed sensitivity and calibration bias were first determined for Surface Water and Ocean Topography (SWOT) satellite Ka-band Radar Interferometer (KaRIn) Normalized Radar Backscatter Cross Section (NRCS) data at VV and HH polarizations. Here, the calibration bias was estimated by comparing the KaRIn NRCS with collocated simulations from a model developed using Global Precipitation Measurement (GPM) satellite Dual-frequency Precipitation Radar (DPR) data. To recalibrate the bias, the correlation coefficient between the KaRIn data and the simulations was estimated, and the data with the corresponding top 10% correlation coefficients were used to estimate the recalibration coefficients. After recalibration, a Ka-band NRCS model was developed from the KaRIn data to retrieve ocean surface wind speeds. Finally, wind speed retrievals were evaluated using the collocated European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis winds, Haiyang-2C scatterometer (HY2C-SCAT) winds and National Data Buoy Center (NDBC) and Tropical Atmosphere Ocean (TAO) buoy winds. Evaluation results show that the Root Mean Square Error (RMSE) at both polarizations is less than 1.52 m\/s, 1.34 m\/s and 1.57 m\/s, respectively, when compared to ECMWF, HY2C-SCAT and buoy collocated winds. Moreover, both the bias and RMSE were constant with the incidence angles and polarizations. This indicates that the winds from the SWOT KaRIn data are capable of correcting the sea state bias for sea surface height products.<\/jats:p>","DOI":"10.3390\/rs16163103","type":"journal-article","created":{"date-parts":[[2024,8,22]],"date-time":"2024-08-22T11:14:41Z","timestamp":1724325281000},"page":"3103","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["NRCS Recalibration and Wind Speed Retrieval for SWOT KaRIn Radar Data"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1121-8980","authenticated-orcid":false,"given":"Lin","family":"Ren","sequence":"first","affiliation":[{"name":"State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China"},{"name":"Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources, Beijing 100081, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China"}]},{"given":"Xiao","family":"Dong","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China"}]},{"given":"Limin","family":"Cui","sequence":"additional","affiliation":[{"name":"Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources, Beijing 100081, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7514-3212","authenticated-orcid":false,"given":"Jingsong","family":"Yang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China"}]},{"given":"Yi","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Space Ocean Remote Sensing and Application, Ministry of Natural Resources, Beijing 100081, China"}]},{"given":"Peng","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China"}]},{"given":"Gang","family":"Zheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China"},{"name":"Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China"}]},{"given":"Lizhang","family":"Zhou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1175\/1520-0426(2003)20<549:TRBWSR>2.0.CO;2","article-title":"The relationship between winds, surface roughness, and radar backscatter at low incidence angles from TRMM precipitation radar measurements","volume":"20","author":"Freilich","year":"2003","journal-title":"J. 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