{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T21:17:48Z","timestamp":1768339068776,"version":"3.49.0"},"reference-count":55,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2023,10,27]],"date-time":"2023-10-27T00:00:00Z","timestamp":1698364800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000270","name":"Natural Environmental Research Council","doi-asserted-by":"publisher","award":["NE\/R003521\/1"],"award-info":[{"award-number":["NE\/R003521\/1"]}],"id":[{"id":"10.13039\/501100000270","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000270","name":"Natural Environmental Research Council","doi-asserted-by":"publisher","award":["DST\/TM\/INDO-UK\/2K17\/64 C & G"],"award-info":[{"award-number":["DST\/TM\/INDO-UK\/2K17\/64 C & G"]}],"id":[{"id":"10.13039\/501100000270","id-type":"DOI","asserted-by":"publisher"}]},{"name":"European Space Agency","award":["NE\/R003521\/1"],"award-info":[{"award-number":["NE\/R003521\/1"]}]},{"name":"European Space Agency","award":["DST\/TM\/INDO-UK\/2K17\/64 C & G"],"award-info":[{"award-number":["DST\/TM\/INDO-UK\/2K17\/64 C & G"]}]},{"name":"National Centre of Earth Observation of the UK","award":["NE\/R003521\/1"],"award-info":[{"award-number":["NE\/R003521\/1"]}]},{"name":"National Centre of Earth Observation of the UK","award":["DST\/TM\/INDO-UK\/2K17\/64 C & G"],"award-info":[{"award-number":["DST\/TM\/INDO-UK\/2K17\/64 C & G"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Water is an essential natural resource, but increasingly water also forms a threat to the human population, with floods being the most common natural disaster worldwide. Earth Observation has the potential for developing cost-effective methods to monitor risk, with free and open data available at the global scale. In this study, we present the application of remote sensing observations to map flooded areas, using the Vembanad-Kol-Wetland system in the southwest of India as a case study. In August 2018, this region experienced an extremely heavy monsoon season, which caused once-in-a-century floods that led to nearly 500 deaths and the displacement of over a million people. We review the use of existing algorithms to map flooded areas in the Lake Vembanad region using the spectral reflectances of the green, red and near-infrared bands from the MSI sensor on board Sentinel-2. Although the MSI sensor has no cloud-penetrating capability, we show that the Modified Normalised Difference Water Index and the Automated Water Extraction Index can be used to generate flood maps from multi-spectral visible remote sensing observations to complement commonly used SAR-based techniques to enhance temporal coverage (from 12 to 5 days). We also show that local knowledge of paddy cultivation practices can be used to map the manoeuvring of water levels and exclude inundated paddy fields to improve the accuracy of flood maps in the study region. The flood mapping addressed here has the potential to become part of a solution package based on multi-spectral visible remote sensing with capabilities to simultaneously monitor water quality and risk of human pathogens in the environment, providing additional important services during natural disasters.<\/jats:p>","DOI":"10.3390\/rs15215139","type":"journal-article","created":{"date-parts":[[2023,10,27]],"date-time":"2023-10-27T09:56:36Z","timestamp":1698400596000},"page":"5139","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Using Multi-Spectral Remote Sensing for Flood Mapping: A Case Study in Lake Vembanad, India"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0224-7547","authenticated-orcid":false,"given":"Gemma","family":"Kulk","sequence":"first","affiliation":[{"name":"Earth Observation Science and Applications, Plymouth Marine Laboratory, Plymouth PL1 3DH, UK"},{"name":"National Centre for Earth Observation, Plymouth Marine Laboratory, Plymouth PL1 3DH, UK"}]},{"given":"Shubha","family":"Sathyendranath","sequence":"additional","affiliation":[{"name":"Earth Observation Science and Applications, Plymouth Marine Laboratory, Plymouth PL1 3DH, UK"},{"name":"National Centre for Earth Observation, Plymouth Marine Laboratory, Plymouth PL1 3DH, UK"}]},{"given":"Trevor","family":"Platt","sequence":"additional","affiliation":[{"name":"Earth Observation Science and Applications, Plymouth Marine Laboratory, Plymouth PL1 3DH, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0136-5445","authenticated-orcid":false,"given":"Grinson","family":"George","sequence":"additional","affiliation":[{"name":"Central Marine Fisheries Research Institute, Kochi 682018, India"}]},{"given":"Anagha Kunhimuthappan","family":"Suresan","sequence":"additional","affiliation":[{"name":"Central Marine Fisheries Research Institute, Kochi 682018, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1132-0192","authenticated-orcid":false,"given":"Nandini","family":"Menon","sequence":"additional","affiliation":[{"name":"Nansen Environmental Research Centre (India), Kochi 682506, India"}]},{"given":"Hayley","family":"Evers-King","sequence":"additional","affiliation":[{"name":"EUMETSAT, 64295 Darmstadt, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1396-3645","authenticated-orcid":false,"given":"Anas","family":"Abdulaziz","sequence":"additional","affiliation":[{"name":"National Institute of Oceanography, Kochi 682018, India"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,27]]},"reference":[{"key":"ref_1","unstructured":"(2022, May 22). 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