{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T14:09:48Z","timestamp":1768313388903,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2020,10,16]],"date-time":"2020-10-16T00:00:00Z","timestamp":1602806400000},"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":["SMOS Expert Support Laboratories Level 1 (SMOS-P7-DME-COM-CCN05-E-R) and the CCI+ Sea Surface Salinity project"],"award-info":[{"award-number":["SMOS Expert Support Laboratories Level 1 (SMOS-P7-DME-COM-CCN05-E-R) and the CCI+ Sea Surface Salinity project"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Spanish Ministry of Economy and Competitiveness, National R+D Plan","award":["L-Band Project ESP2017-89463-C3-1-R"],"award-info":[{"award-number":["L-Band Project ESP2017-89463-C3-1-R"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The error characterization of satellite observations is crucial for blending observations from multiple platforms into a unique dataset and for assimilating them into numerical weather prediction models. In the last years, the triple collocation (TC) technique has been widely used to assess the quality of many geophysical variables acquired with different instruments and at different scales. This paper presents a new formulation of the triple collocation (Correlated Triple Collocation (CTC)) for the case of three datasets that resolve similar spatial scales, with two of them being error-correlated datasets. Besides, the formulation is designed to ensure fast convergence of the error estimators. This approach is of special interest in cases such that finding more than three datasets with uncorrelated errors is not possible and the amount of data is limited. First, a synthetic experiment has been carried out to assess the performance of CTC formulation. As an example of application, the error characterization of three collocated L-band brightness temperature (TB) measurements over land has been performed. Two of the datasets come from ESA (European Space Agency) SMOS (Soil Moisture and Ocean Salinity) mission: one is the reconstructed TB from the operational L1B v620 product, and the other is the reconstructed TB from the operational L1B v620 product resulting from application of an RFI (Radio Frequency Interference) mitigation technique, the nodal sampling (NS). The third is an independent dataset, the TB acquired by a NASA (National Aeronautics and Space Administration) SMAP (Soil Moisture Active Passive) radiometer. Our analysis shows that the application of NS leads to TB error reduction with respect to the current version of SMOS TB in 80% of the points in the global map, with an average reduction of approximately 1 K over RFI-free regions and approximately 1.45 K over strongly RFI-contaminated areas.<\/jats:p>","DOI":"10.3390\/rs12203381","type":"journal-article","created":{"date-parts":[[2020,10,16]],"date-time":"2020-10-16T08:56:48Z","timestamp":1602838608000},"page":"3381","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Triple Collocation Analysis for Two Error-Correlated Datasets: Application to L-Band Brightness Temperatures over Land"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6380-3754","authenticated-orcid":false,"given":"Ver\u00f3nica","family":"Gonz\u00e1lez-Gambau","sequence":"first","affiliation":[{"name":"Department of Physical Oceanography, Institute of Marine Sciences, CSIC and Barcelona Expert Center, Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6103-224X","authenticated-orcid":false,"given":"Antonio","family":"Turiel","sequence":"additional","affiliation":[{"name":"Department of Physical Oceanography, Institute of Marine Sciences, CSIC and Barcelona Expert Center, Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4602-852X","authenticated-orcid":false,"given":"Cristina","family":"Gonz\u00e1lez-Haro","sequence":"additional","affiliation":[{"name":"Department of Physical Oceanography, Institute of Marine Sciences, CSIC and Barcelona Expert Center, Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4749-0292","authenticated-orcid":false,"given":"Justino","family":"Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Department of Physical Oceanography, Institute of Marine Sciences, CSIC and Barcelona Expert Center, Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3178-1554","authenticated-orcid":false,"given":"Estrella","family":"Olmedo","sequence":"additional","affiliation":[{"name":"Department of Physical Oceanography, Institute of Marine Sciences, CSIC and Barcelona Expert Center, Passeig Maritim de la Barceloneta, 37-49, 08003 Barcelona, Spain"}]},{"given":"Roger","family":"Oliva","sequence":"additional","affiliation":[{"name":"Zenithal Blue Technologies S.L.U. for the European Space Agency, 08023 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7626-7033","authenticated-orcid":false,"given":"Manuel","family":"Mart\u00edn-Neira","sequence":"additional","affiliation":[{"name":"European Space Research and Technology Centre, European Space Agency, 2200 AG Noordwijk, The Netherlands"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7755","DOI":"10.1029\/97JC03180","article-title":"Toward the true near-surface wind speed: Error modeling and calibration using triple collocation","volume":"103","author":"Stoffelen","year":"1998","journal-title":"J. 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