{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T03:03:54Z","timestamp":1783134234309,"version":"3.54.6"},"reference-count":51,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,11]],"date-time":"2018-01-11T00:00:00Z","timestamp":1515628800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002830","name":"Centre National d\u2019Etudes Spatiales","doi-asserted-by":"publisher","award":["FOAM"],"award-info":[{"award-number":["FOAM"]}],"id":[{"id":"10.13039\/501100002830","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002830","name":"Centre National d\u2019Etudes Spatiales","doi-asserted-by":"publisher","award":["CTOH"],"award-info":[{"award-number":["CTOH"]}],"id":[{"id":"10.13039\/501100002830","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004794","name":"Centre National de la Recherche Scientifique","doi-asserted-by":"publisher","award":["MISTRAL"],"award-info":[{"award-number":["MISTRAL"]}],"id":[{"id":"10.13039\/501100004794","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Monitoring changes in coastal sea levels is necessary given the impacts of climate change. Information on the sea level and its changes are important parameters in connection to climate change processes. In this study, radar altimetry data from successive satellite missions, European Remote Sensing-2 (ERS-2), Jason-1, Envisat, Jason-2, and Satellite with ARgos and ALtiKa (SARAL), were used to measure sea surface heights (SSH). Altimetry-derived SSH was validated for the southern Bay of Biscay, using records from seven tide gauges located along the French Atlantic coast. More detailed comparisons were performed at La Rochelle, as this was the only tide gauge whose records covered the entire observation period for the different radar altimetry missions. The results of the comparison between the altimetry-based and in-situ SSH, recorded from zero to five kilometers away from the coast, had root mean square errors (RMSE) ranging from 0.08 m to 0.21 m, 0.17 m to 0.34 m, 0.1 m to 0.29 m, 0.18 m to 0.9 m, and 0.22 m to 0.89 m for SARAL, Jason-2, Jason-1, ENVISAT, and ERS-2, respectively. Comparing the missions on the same orbit, ENVISAT had better results than ERS-2, which can be accounted for by the improvements in the sensor mode of operation, whereas the better results obtained using SARAL are related to the first-time use of the Ka-band for an altimetry sensor. For Jason-1 and Jason-2, improvements were found in the ocean retracking algorithm (MLE-4 against MLE-3), and also in the bi-frequency ionosphere and radiometer wet troposphere corrections. Close to the shore, the use of model-based ionosphere (GIM) and wet troposphere (ECMWF) corrections, as applied to land surfaces, reduced the error on the SSH estimates.<\/jats:p>","DOI":"10.3390\/rs10010093","type":"journal-article","created":{"date-parts":[[2018,1,11]],"date-time":"2018-01-11T13:36:15Z","timestamp":1515677775000},"page":"93","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Multi-Satellite Altimeter Validation along the French Atlantic Coast in the Southern Bay of Biscay from ERS-2 to SARAL"],"prefix":"10.3390","volume":"10","author":[{"given":"Phuong","family":"Vu","sequence":"first","affiliation":[{"name":"GET-GRGS, UMR 5563, CNRS\/IRD\/UPS, Observatoire Midi-Pyr\u00e9n\u00e9es, 14 Avenue Edouard Belin, 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fr\u00e9d\u00e9ric","family":"Frappart","sequence":"additional","affiliation":[{"name":"GET-GRGS, UMR 5563, CNRS\/IRD\/UPS, Observatoire Midi-Pyr\u00e9n\u00e9es, 14 Avenue Edouard Belin, 31400 Toulouse, France"},{"name":"LEGOS-GRGS, UMR 5566, CNES\/CNRS\/IRD\/UPS, Observatoire Midi-Pyr\u00e9n\u00e9es, 14 Avenue Edouard Belin, 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1750-2819","authenticated-orcid":false,"given":"Jos\u00e9","family":"Darrozes","sequence":"additional","affiliation":[{"name":"GET-GRGS, UMR 5563, CNRS\/IRD\/UPS, Observatoire Midi-Pyr\u00e9n\u00e9es, 14 Avenue Edouard Belin, 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4023-0161","authenticated-orcid":false,"given":"Vincent","family":"Marieu","sequence":"additional","affiliation":[{"name":"UMR CNRS 5805 EPOC\u2014OASU\u2014Universit\u00e9 de Bordeaux, All\u00e9e Geoffroy Saint-Hilaire CS 50023, 33615 Pessac CEDEX, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabien","family":"Blarel","sequence":"additional","affiliation":[{"name":"LEGOS-GRGS, UMR 5566, CNES\/CNRS\/IRD\/UPS, Observatoire Midi-Pyr\u00e9n\u00e9es, 14 Avenue Edouard Belin, 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guillaume","family":"Ramillien","sequence":"additional","affiliation":[{"name":"GET-GRGS, UMR 5563, CNRS\/IRD\/UPS, Observatoire Midi-Pyr\u00e9n\u00e9es, 14 Avenue Edouard Belin, 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pascal","family":"Bonnefond","sequence":"additional","affiliation":[{"name":"SYRTE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universit\u00e9s, UPMC Univ. Paris 06, LNE, 75014 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florence","family":"Birol","sequence":"additional","affiliation":[{"name":"LEGOS-GRGS, UMR 5566, CNES\/CNRS\/IRD\/UPS, Observatoire Midi-Pyr\u00e9n\u00e9es, 14 Avenue Edouard Belin, 31400 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,11]]},"reference":[{"key":"ref_1","unstructured":"Fu, L.L., and Cazenave, A. (2001). Satellite Altimetry and Earth Sciences: A Handbook of Techniques and Applications, Academic Press."},{"key":"ref_2","unstructured":"Webster, J. (2017). Satellite Altimetry: Principles and Applications in Earth Sciences. 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