{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:18:35Z","timestamp":1760239115224,"version":"build-2065373602"},"reference-count":14,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2020,9,25]],"date-time":"2020-09-25T00:00:00Z","timestamp":1600992000000},"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":["Contract 4000124211\/18\/I-EF"],"award-info":[{"award-number":["Contract 4000124211\/18\/I-EF"]}],"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>The long-term stability of microwave radiometers (MWR) on-board altimetry missions is critical to reduce the uncertainty on the global mean sea level estimate. Harmonization and homogenization steps are applied to MWR observations in that perspective. The Sentinel-3 tandem phase provides a unique opportunity to quantify the uncertainties on the \u201czero-bias line\u201d homogenization approach defined by Bennartz et al. (2020). Initially developed to improve the performance of the wet tropospheric correction retrieval, it is used here to provide a common reference for the inter-calibration between Sentinel-3A and Sentinel-3B MWR. A simplified version of the \u201czero-bias line\u201d approach, a linear correction depending on brightness temperatures, allows to strongly reduce the bias between the two radiometers for both channels (about 0.5 K) and the standard deviation of the difference (0.3 K). The full version of the approach adding a dependency on wind speed has improved the quality of the WTC retrieval (Bennartz et al. 2020) but degrades the performance of the homogenization. It is thus recommended to apply the simplified version of this approach in the processing of fundamental data record. The quantification of the uncertainties on the homogenization approach is only possible due to the ideal configuration of the Sentinel-3 tandem phase. The same dataset and the same metrics could be used to assess other approaches.<\/jats:p>","DOI":"10.3390\/rs12193154","type":"journal-article","created":{"date-parts":[[2020,9,28]],"date-time":"2020-09-28T08:02:58Z","timestamp":1601280178000},"page":"3154","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Assessment of the \u201cZero-Bias Line\u201d Homogenization Method for Microwave Radiometers Using Sentinel-3A and Sentinel-3B Tandem Phase"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7918-2542","authenticated-orcid":false,"given":"Bruno","family":"Picard","sequence":"first","affiliation":[{"name":"Fluctus SAS, 81800 Rabastens, France"}]},{"given":"Ralf","family":"Bennartz","sequence":"additional","affiliation":[{"name":"Earth and Environmental Sciences, Vanderbilt University, Nashville, TN 37240, USA"},{"name":"Space Science and Engineering Center, University of Wisconsin, Madison, WI 53706, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6649-3093","authenticated-orcid":false,"given":"Frank","family":"Fell","sequence":"additional","affiliation":[{"name":"Informus GmbH, 13187 Berlin, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6045-407X","authenticated-orcid":false,"given":"Marie-Laure","family":"Frery","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellite, 31520 Toulouse, France"}]},{"given":"Mathilde","family":"Sim\u00e9on","sequence":"additional","affiliation":[{"name":"Collecte Localisation Satellite, 31520 Toulouse, France"}]},{"given":"Frank","family":"Bordes","sequence":"additional","affiliation":[{"name":"European Space Agency (ESA-ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,25]]},"reference":[{"key":"ref_1","unstructured":"Eumetsat (2020, July 10). 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Remote Sens., submitted."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/19\/3154\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:13:45Z","timestamp":1760177625000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/19\/3154"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,9,25]]},"references-count":14,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2020,10]]}},"alternative-id":["rs12193154"],"URL":"https:\/\/doi.org\/10.3390\/rs12193154","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2020,9,25]]}}}