{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T02:33:47Z","timestamp":1774751627317,"version":"3.50.1"},"reference-count":58,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,9]],"date-time":"2018-01-09T00:00:00Z","timestamp":1515456000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The India-France SARAL\/AltiKa mission is the first Ka-band altimetric mission dedicated to oceanography. The mission objectives are primarily the observation of the oceanic mesoscales but also include coastal oceanography, global and regional sea level monitoring, data assimilation, and operational oceanography. The mission ended its nominal phase after 3 years in orbit and began a new phase (drifting orbit) in July 2016. The objective of this paper is to provide a state of the art of the achievements of the SARAL\/AltiKa mission in terms of quality assessment and unique characteristics of AltiKa data. It shows that the AltiKa data have similar accuracy at the centimeter level in term of absolute water level whatever the method (from local to global) and the type of water surfaces (ocean and lakes). It shows also that beyond the fact that AltiKa data quality meets the expectations and initial mission requirements, the unique characteristics of the altimeter and the Ka-band offer unique contributions in fields that were previously not fully foreseen.<\/jats:p>","DOI":"10.3390\/rs10010083","type":"journal-article","created":{"date-parts":[[2018,1,9]],"date-time":"2018-01-09T14:00:08Z","timestamp":1515506408000},"page":"83","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":69,"title":["The Benefits of the Ka-Band as Evidenced from the SARAL\/AltiKa Altimetric Mission: Quality Assessment and Unique Characteristics of AltiKa Data"],"prefix":"10.3390","volume":"10","author":[{"given":"Pascal","family":"Bonnefond","sequence":"first","affiliation":[{"name":"SYRTE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universit\u00e9s, UPMC Univ. Paris 06, LNE, 75014 Paris, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacques","family":"Verron","sequence":"additional","affiliation":[{"name":"Institut des G\u00e9osciences de l\u2019Environnement (IGE)\/CNRS, 38041 Grenoble, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J\u00e9r\u00e9mie","family":"Aublanc","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"K.","family":"Babu","sequence":"additional","affiliation":[{"name":"Space Applications Centre (ISRO), Ahmedabad 380015, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muriel","family":"Berg\u00e9-Nguyen","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Etudes en G\u00e9ophysique et Oc\u00e9anographie Spatiales (LEGOS), 31400 Toulouse, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mathilde","family":"Cancet","sequence":"additional","affiliation":[{"name":"NOVELTIS, 31670 Lab\u00e8ge, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aditya","family":"Chaudhary","sequence":"additional","affiliation":[{"name":"Space Applications Centre (ISRO), Ahmedabad 380015, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Fran\u00e7ois","family":"Cr\u00e9taux","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Etudes en G\u00e9ophysique et Oc\u00e9anographie Spatiales (LEGOS), 31400 Toulouse, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4661-8274","authenticated-orcid":false,"given":"Fr\u00e9d\u00e9ric","family":"Frappart","sequence":"additional","affiliation":[{"name":"Laboratoire d\u2019Etudes en G\u00e9ophysique et Oc\u00e9anographie Spatiales (LEGOS), 31400 Toulouse, France"},{"name":"G\u00e9osciences Environnement Toulouse (GET), 31400 Toulouse, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bruce","family":"Haines","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Olivier","family":"Laurain","sequence":"additional","affiliation":[{"name":"G\u00e9oazur\u2014Observatoire de la C\u00f4te d\u2019Azur, 06905 Sophia-Antipolis, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Annabelle","family":"Ollivier","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Christophe","family":"Poisson","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pierre","family":"Prandi","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rashmi","family":"Sharma","sequence":"additional","affiliation":[{"name":"Space Applications Centre (ISRO), Ahmedabad 380015, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pierre","family":"Thibaut","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellites (CLS), 31520 Ramonville Saint-Agne, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christopher","family":"Watson","sequence":"additional","affiliation":[{"name":"Surveying and Spatial Science Group, School of Geography and Environmental Studies, University of Tasmania, Hobart 7001, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1080\/01490419.2014.1000471","article-title":"The SARAL\/AltiKa altimetry satellite mission","volume":"38","author":"Verron","year":"2015","journal-title":"Mar. 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