{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T18:22:12Z","timestamp":1779128532995,"version":"3.51.4"},"reference-count":30,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,11]],"date-time":"2021-02-11T00:00:00Z","timestamp":1613001600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000844","name":"European Space Agency","doi-asserted-by":"publisher","award":["S3MPC.1222.ACR-VITO.i1r0"],"award-info":[{"award-number":["S3MPC.1222.ACR-VITO.i1r0"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>To validate the iCOR atmospheric correction algorithm applied to the Sentinel-3 Ocean and Land Color Instrument (OLCI), Top-of-Atmosphere (TOA) observations over land, globally retrieved Aerosol Optical Thickness (AOT), Top-of-Canopy (TOC) reflectance, and Vegetation Indices (VIs) were intercompared with (i) AERONET AOT and AERONET-based TOC reflectance simulations, (ii) RadCalNet surface reflectance observations, and (iii) SYN Level 2 (L2) AOT, TOC reflectance, and VIs. The results reveal that, overall, iCOR\u2019s statistical and temporal consistency is high. iCOR AOT retrievals overestimate relative to AERONET, but less than SYN L2. iCOR and SYN L2 TOC reflectances exhibit a negative bias of ~\u22120.01 and \u22120.02, respectively, in the Blue bands compared to the simulations. This diminishes for RED and NIR, except for a +0.02 bias for SYN L2 in the NIR. The intercomparison with RadCalNet shows relative differences &lt; \u00b16%, except for bands Oa02 (Blue) and Oa21 (NIR), which is likely related to the reported OLCI \u201cexcess of brightness\u201d. The intercomparison between iCOR and SYN L2 showed R2 = 0.80\u20130.93 and R2 = 0.92\u20130.96 for TOC reflectance and VIs, respectively. iCOR\u2019s higher temporal smoothness compared to SYN L2 does not propagate into a significantly higher smoothness for TOC reflectance and VIs. Altogether, we conclude that iCOR is well suitable to retrieve statistically and temporally consistent AOT, TOC reflectance, and VIs over land surfaces from Sentinel-3\/OLCI observations.<\/jats:p>","DOI":"10.3390\/rs13040654","type":"journal-article","created":{"date-parts":[[2021,2,12]],"date-time":"2021-02-12T18:45:00Z","timestamp":1613155500000},"page":"654","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["iCOR Atmospheric Correction on Sentinel-3\/OLCI over Land: Intercomparison with AERONET, RadCalNet, and SYN Level-2"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6394-9809","authenticated-orcid":false,"given":"Erwin","family":"Wolters","sequence":"first","affiliation":[{"name":"Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carolien","family":"Tot\u00e9","sequence":"additional","affiliation":[{"name":"Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0194-7100","authenticated-orcid":false,"given":"Sindy","family":"Sterckx","sequence":"additional","affiliation":[{"name":"Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4249-4489","authenticated-orcid":false,"given":"Stefan","family":"Adriaensen","sequence":"additional","affiliation":[{"name":"Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claire","family":"Henocq","sequence":"additional","affiliation":[{"name":"ACRI-ST, 260 Route du Pin Montard, BP 234, 06904 Sophia-Antipolis, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J\u00e9r\u00f4me","family":"Bruniquel","sequence":"additional","affiliation":[{"name":"ACRI-ST, 260 Route du Pin Montard, BP 234, 06904 Sophia-Antipolis, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silvia","family":"Scifoni","sequence":"additional","affiliation":[{"name":"Serco Italia SpA, Via Sciadonna 24-26, 00044 Frascati, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steffen","family":"Dransfeld","sequence":"additional","affiliation":[{"name":"European Space Agency Centre for Earth Observation (ESA-ESRIN), Largo Galileo Galilei, 1, 00044 Frascati, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.rse.2011.07.024","article-title":"The global monitoring for environment and security (GMES) sentinel-3 mission","volume":"120","author":"Donlon","year":"2012","journal-title":"Remote Sens. 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