{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T13:57:42Z","timestamp":1784210262728,"version":"3.55.0"},"reference-count":51,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,3,19]],"date-time":"2021-03-19T00:00:00Z","timestamp":1616112000000},"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":["Dragon 4 Cooperation Project ID 32235"],"award-info":[{"award-number":["Dragon 4 Cooperation Project ID 32235"]}],"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>Satellite synthetic aperture radar (SAR) is a unique tool to collect measurements over sea surface but the physical interpretation of such data is not always straightforward. Among the different sea targets of interest, low-backscattering areas are often associated to marine oil pollution even if several physical phenomena may also result in low-backscattering patches at sea. In this study, the effects of low-backscattering areas of anthropogenic and natural origin on the azimuth autocorrelation function (AACF) are analyzed using VV-polarized SAR measurements. Two objective metrics are introduced to quantify the deviation of the AACF evaluated over low-backscattering areas with reference to slick-free sea surface. Experiments, undertaken on six Sentinel-1 SAR scenes, collected in Interferometric Wide Swath VV+VH imaging mode over large low-backscattering areas of different origin under low-to-moderate wind conditions (speed \u2264 7 m\/s), spanning a wide range of incidence angles (from about 30\u00b0 up to 46\u00b0), demonstrated that the AACF evaluated within low-backscattering sea areas remarkably deviates from the slick-free sea surface one and the largest deviation is observed over oil slicks.<\/jats:p>","DOI":"10.3390\/rs13061183","type":"journal-article","created":{"date-parts":[[2021,3,21]],"date-time":"2021-03-21T23:47:41Z","timestamp":1616370461000},"page":"1183","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["A Sensitivity Analysis on the Spectral Signatures of Low-Backscattering Sea Areas in Sentinel-1 SAR Images"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9566-3258","authenticated-orcid":false,"given":"Valeria","family":"Corcione","sequence":"first","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5523-7609","authenticated-orcid":false,"given":"Andrea","family":"Buono","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4567-0377","authenticated-orcid":false,"given":"Ferdinando","family":"Nunziata","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8363-3502","authenticated-orcid":false,"given":"Maurizio","family":"Migliaccio","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"},{"name":"Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s41467-018-03158-3","article-title":"Ocean Science Research Is Key for a Sustainable Future","volume":"9","author":"Visbeck","year":"2018","journal-title":"Nat. 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