{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T22:19:16Z","timestamp":1775081956205,"version":"3.50.1"},"reference-count":29,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T00:00:00Z","timestamp":1638748800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Finance Science and Technology Project of Hainan Province","award":["ZDYF2020010"],"award-info":[{"award-number":["ZDYF2020010"]}]},{"name":"Finance Science and Technology Project of Hainan Province","award":["ZDYF2019117"],"award-info":[{"award-number":["ZDYF2019117"]}]},{"name":"National Program on Global Change and Air\u2013Sea Interaction","award":["GASI-02-PACINDYGST2-03"],"award-info":[{"award-number":["GASI-02-PACINDYGST2-03"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In recent years, coral reef ecosystems have been affected by global climate change and human factors, resulting in frequent coral bleaching events. A severe coral bleaching event occurred in the northwest of Hainan Island, South China Sea, in 2020. In this study, we used the CoralTemp sea surface temperature (SST) and Sentinel-2B imagery to detect the coral bleaching event. From 31 May to 3 October, the average SST of the study area was 31.01 \u00b0C, which is higher than the local bleaching warning threshold value of 30.33 \u00b0C. In the difference images of 26 July and 4 September, a wide range of coral bleaching was found. According to the temporal variation in single band reflectance, the development process of bleaching is consistent with the changes in coral bleaching thermal alerts. The results show that the thermal stress level is an effective parameter for early warning of large-scale coral bleaching. High-resolution difference images can be used to detect the extent of coral bleaching. The combination of the two methods can provide better support for coral protection and research.<\/jats:p>","DOI":"10.3390\/rs13234948","type":"journal-article","created":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T22:18:42Z","timestamp":1638829122000},"page":"4948","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Detecting 2020 Coral Bleaching Event in the Northwest Hainan Island Using CoralTemp SST and Sentinel-2B MSI Imagery"],"prefix":"10.3390","volume":"13","author":[{"given":"Bailu","family":"Liu","sequence":"first","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"},{"name":"Sanya Oceanographic Institution, Ocean University of China, Sanya 572024, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9902-8035","authenticated-orcid":false,"given":"Lei","family":"Guan","sequence":"additional","affiliation":[{"name":"College of Marine Technology, Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"},{"name":"Sanya Oceanographic Institution, Ocean University of China, Sanya 572024, China"},{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China"}]},{"given":"Hong","family":"Chen","sequence":"additional","affiliation":[{"name":"Hainan South China Sea Institute of Tropical Ocean, Sanya 572024, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1007\/s00338-019-01844-2","article-title":"The 2014\u20132017 global-scale coral bleaching event: Insights and impacts","volume":"38","author":"Eakin","year":"2019","journal-title":"Coral Reefs"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1093\/icb\/34.1.115","article-title":"Biodiversity of Coral Reefs: What Are We Losing and Why?","volume":"34","author":"Sebens","year":"1994","journal-title":"Am. 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