{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T06:33:08Z","timestamp":1785393188738,"version":"3.55.0"},"reference-count":25,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,11,30]],"date-time":"2022-11-30T00:00:00Z","timestamp":1669766400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Centre National d\u2019Etudes Spatiales (French contributions) and the Jet Propulsion Laboratory, California Institute of Technology (U.S contributions)","award":["80NM0018D0004"],"award-info":[{"award-number":["80NM0018D0004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Surface Water and Ocean Topography (SWOT) mission will be affected by various sources of systematic errors, which are correlated in space and in time. Their amplitude before calibration might be as large as tens of centimeters, i.e., able to dominate the mission error budget. To reduce their magnitude, we developed so-called data-driven (or empirical) calibration algorithms. This paper provided a summary of the overall problem, and then presented the calibration framework used for SWOT, as well as the pre-launch performance simulations. We presented two complete algorithm sequences that use ocean measurements to calibrate KaRIN globally. The simple and robust Level-2 algorithm was implemented in the ground segment to control the main source of error of SWOT\u2019s hydrology products. In contrast, the more sophisticated Level-3 (multi-mission) algorithm was developed to improve the accuracy of ocean products, as well as the one-day orbit of the SWOT mission. The Level-2 algorithm yielded a mean inland error of 3\u20136 cm, i.e., a margin of 25\u201380% (of the signal variance) with respect to the error budget requirements. The Level-3 algorithm yielded ocean residuals of 1 cm, i.e., a variance reduction of 60\u201380% with respect to the Level-2 algorithm.<\/jats:p>","DOI":"10.3390\/rs14236070","type":"journal-article","created":{"date-parts":[[2022,11,30]],"date-time":"2022-11-30T07:10:27Z","timestamp":1669792227000},"page":"6070","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Data-Driven Calibration Algorithm and Pre-Launch Performance Simulations for the SWOT Mission"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3644-2495","authenticated-orcid":false,"given":"G\u00e9rald","family":"Dibarboure","sequence":"first","affiliation":[{"name":"Centre National d\u2019Etudes Spatiales (CNES), 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cl\u00e9ment","family":"Ubelmann","sequence":"additional","affiliation":[{"name":"DATLAS, Maison Climat Plan\u00e8te, 70 rue de la Physique, 38400 Saint Martin D\u2019H\u00e8res, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin","family":"Flamant","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fr\u00e9d\u00e9ric","family":"Briol","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eva","family":"Peral","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory (JPL), California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geoffroy","family":"Bracher","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oscar","family":"Vergara","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yannice","family":"Faug\u00e8re","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fran\u00e7ois","family":"Soulat","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicolas","family":"Picot","sequence":"additional","affiliation":[{"name":"Centre National d\u2019Etudes Spatiales (CNES), 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"232","DOI":"10.3389\/fmars.2019.00232","article-title":"Global Observations of Fine-Scale Ocean Surface Topography with the Surface Water and Ocean Topography (SWOT) Mission","volume":"6","author":"Morrow","year":"2019","journal-title":"Front. 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