{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:06:49Z","timestamp":1760242009387,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,11,15]],"date-time":"2018-11-15T00:00:00Z","timestamp":1542240000000},"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":["4000117101\/16\/I\/BG","4000122240\/17\/I-BG"],"award-info":[{"award-number":["4000117101\/16\/I\/BG","4000122240\/17\/I-BG"]}],"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>This work presents calibration results for the altimeter of Sentinel-3A Surface Topography Mission as determined at the Permanent Facility for Altimetry Calibration in west Crete, Greece. The facility has been providing calibration services for more than 15 years for all past (i.e., Envisat, Jason-1, Jason-2, SARAL\/AltiKa, HY-2A) and current (i.e., Sentinel-3A, Sentinel-3B, Jason-3) satellite altimeters. The groundtrack of the Pass No.14 of Sentinel-3A ascends west of the Gavdos island and continues north to the transponder site on the mountains of west Crete. This pass has been calibrated using three independent techniques activated at various sites in the region: (1) the transponder approach for its range bias, (2) the sea-surface method for the estimation of altimeter bias for its sea-surface heights, and (c) the cross-over analysis for inspecting height observations with respect to Jason-3. The other Pass No.335 of Sentinel-3A descends from southwest of Crete to south and intersects the Gavdos calibration site. Additionally, calibration values for this descending pass are presented, applying sea-surface calibration and crossover analysis. An uncertainty analysis for the altimeter biases derived by the transponder and by sea-surface calibrations is also introduced following the new standard of Fiducial Reference Measurements.<\/jats:p>","DOI":"10.3390\/rs10111808","type":"journal-article","created":{"date-parts":[[2018,11,15]],"date-time":"2018-11-15T11:32:47Z","timestamp":1542281567000},"page":"1808","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Absolute Calibration of the European Sentinel-3A Surface Topography Mission over the Permanent Facility for Altimetry Calibration in west Crete, Greece"],"prefix":"10.3390","volume":"10","author":[{"given":"Stelios","family":"Mertikas","sequence":"first","affiliation":[{"name":"Geodesy and Geomatics Engineering Laboratory, Technical University of Crete, GR-73100 Chania, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Craig","family":"Donlon","sequence":"additional","affiliation":[{"name":"European Space Agency\/European Space Research and Technology Centre (ESA\/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pierre","family":"F\u00e9m\u00e9nias","sequence":"additional","affiliation":[{"name":"European Space Agency\/European Space Research Institute (ESA\/ESRIN), Via Galileo Galilei, I-00044 Frascati, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Constantin","family":"Mavrocordatos","sequence":"additional","affiliation":[{"name":"European Space Agency\/European Space Research and Technology Centre (ESA\/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Demitris","family":"Galanakis","sequence":"additional","affiliation":[{"name":"Space Geomatica P.C., Xanthoudidou 10A, GR-73132 Chania, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Achilles","family":"Tripolitsiotis","sequence":"additional","affiliation":[{"name":"Space Geomatica P.C., Xanthoudidou 10A, GR-73132 Chania, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xenophon","family":"Frantzis","sequence":"additional","affiliation":[{"name":"Geodesy and Geomatics Engineering Laboratory, Technical University of Crete, GR-73100 Chania, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Costas","family":"Kokolakis","sequence":"additional","affiliation":[{"name":"Geodesy and Geomatics Engineering Laboratory, Technical University of Crete, GR-73100 Chania, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3797-8016","authenticated-orcid":false,"given":"Ilias N.","family":"Tziavos","sequence":"additional","affiliation":[{"name":"Department of Geodesy and Surveying, Aristotle University of Thessaloniki, University Box 440, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2475-2568","authenticated-orcid":false,"given":"George","family":"Vergos","sequence":"additional","affiliation":[{"name":"Department of Geodesy and Surveying, Aristotle University of Thessaloniki, University Box 440, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thierry","family":"Guinle","sequence":"additional","affiliation":[{"name":"Centre National d\u2019 Etudes Spatiales (CNES), 31401 Toulouse, CEDEX, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,15]]},"reference":[{"key":"ref_1","unstructured":"(2018, July 20). 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