{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T15:14:38Z","timestamp":1772032478374,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2023,8,8]],"date-time":"2023-08-08T00:00:00Z","timestamp":1691452800000},"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":["2022YFD2401304"],"award-info":[{"award-number":["2022YFD2401304"]}],"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":["SCKJ-JYRC-2022-101"],"award-info":[{"award-number":["SCKJ-JYRC-2022-101"]}],"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":["SKJC-2022-01-001"],"award-info":[{"award-number":["SKJC-2022-01-001"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Project of Sanya Yazhou Bay Science and Technology City","award":["2022YFD2401304"],"award-info":[{"award-number":["2022YFD2401304"]}]},{"name":"Project of Sanya Yazhou Bay Science and Technology City","award":["SCKJ-JYRC-2022-101"],"award-info":[{"award-number":["SCKJ-JYRC-2022-101"]}]},{"name":"Project of Sanya Yazhou Bay Science and Technology City","award":["SKJC-2022-01-001"],"award-info":[{"award-number":["SKJC-2022-01-001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Since the launch of CFOSAT on 29 October 2018, more than three years of observational data of ocean wave spectra with a frequency range of 0.02\u20130.26 Hz and a horizontal resolution of 70\u201390 km have been obtained. This study compares wave spectra retrieved from 6\u00b0, 8\u00b0, and 10\u00b0 incidence angle beams and their combination provided by CFOSAT with corresponding data from 98 buoys from the National Data Buoy Center (NDBC) in order to validate the remote sensing wave spectral accuracy from 1 January 2020 to 31 December 2022. The correlation coefficient of frequency spectra (Rs) between CFOSAT and buoys is used to represent the accuracy of the spectral form; the root mean square (RMS) of the significant wave height (SWH) is used to represent the accuracy of the total energy. The results indicate that CFOSAT can retrieve reliable wave frequency spectral forms with a high significant wave height (Rs &gt; 0.8 when SWH &gt; 3 m; RS &lt; 0.4 when SWH &lt; 1 m). The low-frequency noise in the swell part causes the main error, the RMS of the swell height is 0.4 m whereas the RMS of wind wave height is 0.24 m, and the mask filter used for spectral partitioned provided by CFOSAT can eliminate the low-frequency noise and improve the Rs of 10\u00b0 beam wave spectra from 0.59 to 0.64. For the wind wave spectra, the correct spectra have been achieved and the mask filter cannot improve the accuracy. The wave spectra from the 10\u00b0 beam without mask filtering provides the best estimation of total energy, the RMS of SWH is 0.23 m, after the mask filtering, the best estimation of spectral form can be achieved, the Rs is 0.64. The novelty of this study is that we found the strong correlation between SWH and Rs, where the scatter of SWH and Rs can be fitted as: Rs = 1 \u2212 exp(\u22120.89\u00b7SWH + 0.20); according to this approximate formula, we can estimate the reliability of wave spectra provided by CFOSAT according to the SWH in any region, which is important for wave spectral assimilation in the numerical model. The validation of wave direction indicates that the accuracy of wave spectra in the directional component is poor; further research is needed on the causes of directional errors. Generally, this study is not only an evaluation of the quality of the CFOSAT spectral data, but also an important reference for a series of research requiring the CFOSAT spectral data.<\/jats:p>","DOI":"10.3390\/rs15163918","type":"journal-article","created":{"date-parts":[[2023,8,8]],"date-time":"2023-08-08T12:38:59Z","timestamp":1691498339000},"page":"3918","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Validation of the Ocean Wave Spectrum from the Remote Sensing Data of the Chinese\u2013French Oceanography Satellite"],"prefix":"10.3390","volume":"15","author":[{"given":"Songlin","family":"Li","sequence":"first","affiliation":[{"name":"College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China"}]},{"given":"Huaming","family":"Yu","sequence":"additional","affiliation":[{"name":"College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China"},{"name":"Sanya Oceanographic Institution, Ocean University of China, Sanya 572000, China"}]},{"given":"Kejian","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China"}]},{"given":"Xunqiang","family":"Yin","sequence":"additional","affiliation":[{"name":"The First Institute of Oceanography, and Key Laboratory of Marine Science and Numerical Modeling, Ministry of Natural Resources, Qingdao 266100, China"}]},{"given":"Shuyan","family":"Lang","sequence":"additional","affiliation":[{"name":"National Satellite Ocean Application Service, Beijing 100081, China"}]},{"given":"Jiacheng","family":"Ye","sequence":"additional","affiliation":[{"name":"College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2820","DOI":"10.1175\/2009JPO4169.1","article-title":"Observation and estimation of Lagrangian, Stokes, and Eulerian currents induced by wind and waves at the sea surface","volume":"39","author":"Ardhuin","year":"2009","journal-title":"J. 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