{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T07:56:26Z","timestamp":1761897386240,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2020,10,2]],"date-time":"2020-10-02T00:00:00Z","timestamp":1601596800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Paul G. Allen\u2019s Vulcan Inc.","award":["Allen Coral Atlas"],"award-info":[{"award-number":["Allen Coral Atlas"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>We present a new method for the detection of coral bleaching using satellite time-series data. While the detection of coral bleaching from satellite imagery is difficult due to the low signal-to-noise ratio of benthic reflectance, we overcame this difficulty using three approaches: 1) specialized pre-processing developed for Planet Dove satellites, 2) a time-series approach for determining baseline reflectance statistics, and 3) a regional filter based on a preexisting map of live coral. The time-series was divided into a baseline period (April-July 2019), when no coral bleaching was known to have taken place, and a bleaching period (August 2019-present), when the bleaching was known to have occurred based on field data. The identification of the bleaching period allowed the computation of a Standardized Bottom Reflectance (SBR) for each region. SBR transforms the weekly bottom reflectance into a value relative to the baseline reflectance distribution statistics, increasing the sensitivity to bleaching detection. We tested three scales of the temporal smoothing of the SBR (weekly, cumulative average, and three-week moving average). Our field verification of coral bleaching throughout the main Hawaiian Islands showed that the cumulative average and three-week moving average smoothing detected the highest proportion of coral bleaching locations, correctly identifying 11 and 10 out of 18 locations, respectively. However, the three-week moving average provided a better sensitivity in coral bleaching detection, with a performance increase of at least one standard deviation, which helps define the confidence level of a detected bleaching event.<\/jats:p>","DOI":"10.3390\/rs12193219","type":"journal-article","created":{"date-parts":[[2020,10,2]],"date-time":"2020-10-02T09:39:25Z","timestamp":1601631565000},"page":"3219","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Coral Bleaching Detection in the Hawaiian Islands Using Spatio-Temporal Standardized Bottom Reflectance and Planet Dove Satellites"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1178-2776","authenticated-orcid":false,"given":"Yaping","family":"Xu","sequence":"first","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0428-2909","authenticated-orcid":false,"given":"Nicholas R.","family":"Vaughn","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]},{"given":"David E.","family":"Knapp","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3509-8530","authenticated-orcid":false,"given":"Roberta E.","family":"Martin","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]},{"given":"Christopher","family":"Balzotti","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0275-4872","authenticated-orcid":false,"given":"Jiwei","family":"Li","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7083-2377","authenticated-orcid":false,"given":"Shawna A.","family":"Foo","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7893-6421","authenticated-orcid":false,"given":"Gregory P.","family":"Asner","sequence":"additional","affiliation":[{"name":"Center for Global Discovery and Conservation Science (GDCS), Arizona State University, Tempe, AZ 85281, USA"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1038\/nature02691","article-title":"Confronting the coral reef crisis","volume":"429","author":"Bellwood","year":"2004","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1016\/S0921-8009(99)00009-9","article-title":"Ecological goods and services of coral reef ecosystems","volume":"29","author":"Moberg","year":"1999","journal-title":"Ecol. 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