{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T15:00:06Z","timestamp":1772204406238,"version":"3.50.1"},"reference-count":21,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,9,25]],"date-time":"2024-09-25T00:00:00Z","timestamp":1727222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Centre National d\u2019Etudes Spatiales, DUACS grant"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The SWOT satellite, carrying the KaRIN first wide-swath onboard altimeter, was launched in December 2022, and has now delivered more than a year of surface water elevation data over the ocean and inland lakes\/rivers. These data are affected by systematic errors which constitute the dominant part of the error budget at scales larger than a few thousands of kilometers. Some strategies for their estimation and calibration were explored during the pre-launch studies with performance estimations. Now, based on the real data, we propose in this study to assess the systematic error budget with statistical methods relying on spectral and co-spectral analysis. From this assessment, suggesting very low error levels (below requirements), we propose the implementation of the calibration algorithms at Level-2 and Level-3 with a few minor adjustments justified by the error spectra. The calibrated products are then validated with usual CalVal metrics.<\/jats:p>","DOI":"10.3390\/rs16193558","type":"journal-article","created":{"date-parts":[[2024,9,25]],"date-time":"2024-09-25T04:01:24Z","timestamp":1727236884000},"page":"3558","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Data-Driven Calibration of SWOT\u2019s Systematic Errors: First In-Flight Assessment"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3609-2798","authenticated-orcid":false,"given":"Cl\u00e9ment","family":"Ubelmann","sequence":"first","affiliation":[{"name":"Datlas, 38000 Grenoble, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3644-2495","authenticated-orcid":false,"given":"G\u00e9rald","family":"Dibarboure","sequence":"additional","affiliation":[{"name":"Centre National d\u2019Etudes Spatial, 31401 Toulouse, France"}]},{"given":"Benjamin","family":"Flamant","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 31520 Ramonville Saint-Agne, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4922-4198","authenticated-orcid":false,"given":"Antoine","family":"Delepoulle","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 31520 Ramonville Saint-Agne, France"}]},{"given":"Maxime","family":"Vayre","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 31520 Ramonville Saint-Agne, France"}]},{"given":"Yannice","family":"Faug\u00e8re","sequence":"additional","affiliation":[{"name":"Centre National d\u2019Etudes Spatial, 31401 Toulouse, France"}]},{"given":"Pierre","family":"Prandi","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 31520 Ramonville Saint-Agne, France"}]},{"given":"Matthias","family":"Raynal","sequence":"additional","affiliation":[{"name":"Centre National d\u2019Etudes Spatial, 31401 Toulouse, France"}]},{"given":"Fr\u00e9d\u00e9ric","family":"Briol","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 31520 Ramonville Saint-Agne, France"}]},{"given":"Geoffroy","family":"Bracher","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 31520 Ramonville Saint-Agne, France"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4906-9584","authenticated-orcid":false,"given":"Emeline","family":"Cadier","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites, 31520 Ramonville Saint-Agne, France"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,25]]},"reference":[{"key":"ref_1","unstructured":"Fu, L.-L., Alsdorf, D., Morrow, R., Rodriguez, E., and Mognard, N. 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Proceedings of the ICASSP 2022\u20142022 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Singapore.","DOI":"10.1109\/ICASSP43922.2022.9746889"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/16\/19\/3558\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:02:09Z","timestamp":1760112129000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/16\/19\/3558"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,9,25]]},"references-count":21,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2024,10]]}},"alternative-id":["rs16193558"],"URL":"https:\/\/doi.org\/10.3390\/rs16193558","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,9,25]]}}}