{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T02:48:40Z","timestamp":1774320520949,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,11]],"date-time":"2022-02-11T00:00:00Z","timestamp":1644537600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Synthetic Aperture Radar (SAR) in wave mode is a powerful tool for monitoring sea states in terms of long-period ocean swells of a specific wave directional partition. Since 2016, SARs aboard Sentinel-1A\/B operating in wave mode have provided ocean swell spectra dataset as Level-2 Ocean products on a continuous and global basis over open oceans. Furthermore, Level-3 swell products are processed by Copernicus Marine Environment Monitoring Services (CMEMS) taking the benefit of the unique \u201cfireworks\u201d analysis. In this paper, swell wave heights from Sentinel-1A\/B wave mode during the period from June 2016 to June 2020 are evaluated. The reference data include the collocated in situ measurements from directional wave buoys and WaveWatch III (WW3) hindcasts. Assessment results show systematic overestimation of approximately 0.2 m in terms of the partitioned swell heights for Sentinel-1A\/B Level-2 products compared to the directional buoy observations in eastern Pacific and the western Atlantic. Based on the reliable SAR-WW3 collocations after quality-controls, empirical corrections have been proposed for Sentinel-1 Level-2 swell heights. Independent comparisons against WW3 hindcasts and buoy observations demonstrate the validity of our postprocessing correction for both Level-2 and Level-3 swell heights by eliminating the biases and reducing the root mean square errors. The consistency between CMEMS Level-3 swells and buoy in situ is also examined and discussed by case studies.<\/jats:p>","DOI":"10.3390\/rs14040862","type":"journal-article","created":{"date-parts":[[2022,2,13]],"date-time":"2022-02-13T20:34:45Z","timestamp":1644784485000},"page":"862","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Assessment of Ocean Swell Height Observations from Sentinel-1A\/B Wave Mode against Buoy In Situ and Modeling Hindcasts"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4084-936X","authenticated-orcid":false,"given":"He","family":"Wang","sequence":"first","affiliation":[{"name":"National Ocean Technology Center, Ministry of Natural Resources, Tianjin 300112, China"},{"name":"Laboratoire d\u2019Oc\u00e9anographie Physique Spatiale, Centre de Brest, Ifremer, 29280 Plouzan\u00e9, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1250-4436","authenticated-orcid":false,"given":"Alexis","family":"Mouche","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Oc\u00e9anographie Physique Spatiale, Centre de Brest, Ifremer, 29280 Plouzan\u00e9, France"}]},{"given":"Romain","family":"Husson","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 29280 Plouzan\u00e9, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9113-9467","authenticated-orcid":false,"given":"Antoine","family":"Grouazel","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Oc\u00e9anographie Physique Spatiale, Centre de Brest, Ifremer, 29280 Plouzan\u00e9, France"}]},{"given":"Bertrand","family":"Chapron","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Oc\u00e9anographie Physique Spatiale, Centre de Brest, Ifremer, 29280 Plouzan\u00e9, France"}]},{"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"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1461","DOI":"10.1175\/2010JCLI3718.1","article-title":"A Global View on the Wind Sea and Swell Climate and Variability from ERA-40","volume":"24","author":"Semedo","year":"2011","journal-title":"J. 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