{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T14:48:45Z","timestamp":1773931725221,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2020,12,10]],"date-time":"2020-12-10T00:00:00Z","timestamp":1607558400000},"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":["ESA PO 5001025474"],"award-info":[{"award-number":["ESA PO 5001025474"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000844","name":"European Space Agency","doi-asserted-by":"publisher","award":["ESA CN 4000128320\/19\/NL\/FF\/ab"],"award-info":[{"award-number":["ESA CN 4000128320\/19\/NL\/FF\/ab"]}],"id":[{"id":"10.13039\/501100000844","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["RTI2018-099008-B-C21 \/ AEI \/ 10.13039\/501100011033"],"award-info":[{"award-number":["RTI2018-099008-B-C21 \/ AEI \/ 10.13039\/501100011033"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Maria de Maeztu","award":["MDM-2016-0600"],"award-info":[{"award-number":["MDM-2016-0600"]}]},{"name":"Multidisciplinary drifting Observatory for the Study of the Arctic Climate","award":["MOSAiC20192020, NSF-1820927, NFR-287871"],"award-info":[{"award-number":["MOSAiC20192020, NSF-1820927, NFR-287871"]}]},{"name":"Polastern Expedition","award":["AWI_PS122_00"],"award-info":[{"award-number":["AWI_PS122_00"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The FSSCat mission was the 2017 ESA Sentinel Small Satellite (S\u23033) Challenge winner and the Copernicus Masters competition overall winner. It was successfully launched on 3 September 2020 onboard the VEGA SSMS PoC (VV16). FSSCat aims to provide coarse and downscaled soil moisture data and over polar regions, sea ice cover, and coarse resolution ice thickness using a combined L-band microwave radiometer and GNSS-Reflectometry payload. As part of the calibration and validation activities of FSSCat, a GNSS-R instrument was deployed as part of the MOSAiC polar expedition. The Multidisciplinary drifting Observatory for the Study of Arctic Climate expedition was an international one-year-long field experiment led by the Alfred Wegener Institute to study the climate system and the impact of climate change in the Arctic Ocean. This paper presents the first results of the PYCARO-2 instrument, focused on the GNSS-R techniques used to measure snow and ice thickness of an ice floe. The Interference Pattern produced by the combination of the GNSS direct and reflected signals over the sea-ice has been modeled using a four-layer model. The different thicknesses of the substrate layers (i.e., snow and ice) are linked to the position of the fringes of the interference pattern. Data collected by MOSAiC GNSS-R instrument between December 2019 and January 2020 for different GNSS constellations and frequencies are presented and analyzed, showing that under general conditions, sea ice and snow thickness can be retrieved using multiangular and multifrequency data.<\/jats:p>","DOI":"10.3390\/rs12244038","type":"journal-article","created":{"date-parts":[[2020,12,10]],"date-time":"2020-12-10T08:59:34Z","timestamp":1607590774000},"page":"4038","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Snow and Ice Thickness Retrievals Using GNSS-R: Preliminary Results of the MOSAiC Experiment"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6441-6676","authenticated-orcid":false,"given":"Joan Francesc","family":"Munoz-Martin","sequence":"first","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2736-1028","authenticated-orcid":false,"given":"Adrian","family":"Perez","sequence":"additional","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9514-4992","authenticated-orcid":false,"given":"Adriano","family":"Camps","sequence":"additional","affiliation":[{"name":"CommSensLab\u2014UPC, Universitat Polit\u00e8cnica de Catalunya\u2014BarcelonaTech, and IEEC\/CTE-UPC, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9173-8355","authenticated-orcid":false,"given":"Serni","family":"Rib\u00f3","sequence":"additional","affiliation":[{"name":"Institute of Space Sciences (ICE, CSIC), Campus UAB, 08193 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya IEEC, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8908-0972","authenticated-orcid":false,"given":"Estel","family":"Cardellach","sequence":"additional","affiliation":[{"name":"Institute of Space Sciences (ICE, CSIC), Campus UAB, 08193 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya IEEC, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7316-8320","authenticated-orcid":false,"given":"Julienne","family":"Stroeve","sequence":"additional","affiliation":[{"name":"Centre for Earth Observation Science, 535 Wallace Building, University of Manitoba, Winnipeg, MB R3T 2N2, Canada"},{"name":"CPOM, University of College London, Gower Street, London WC1E 6BT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5133-2676","authenticated-orcid":false,"given":"Vishnu","family":"Nandan","sequence":"additional","affiliation":[{"name":"Centre for Earth Observation Science, 535 Wallace Building, University of Manitoba, Winnipeg, MB R3T 2N2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4029-1936","authenticated-orcid":false,"given":"Polona","family":"Itkin","sequence":"additional","affiliation":[{"name":"Department of Physics and Technology, UiT The Arctic University of Norway, 8514 Troms\u00f8, Norway"},{"name":"Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO 80523, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1463-4832","authenticated-orcid":false,"given":"Rasmus","family":"Tonboe","sequence":"additional","affiliation":[{"name":"Danish Meteorological Institute, Lyngbyvej 100, DK-2100 Copenhagen \u00d8, Denmark"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1412-3146","authenticated-orcid":false,"given":"Stefan","family":"Hendricks","sequence":"additional","affiliation":[{"name":"Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Klussmanstr 3D, 27570 Bremerhaven, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcus","family":"Huntemann","sequence":"additional","affiliation":[{"name":"Institute of Environmental Physics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0165-8448","authenticated-orcid":false,"given":"Gunnar","family":"Spreen","sequence":"additional","affiliation":[{"name":"Institute of Environmental Physics, University of Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2108-5408","authenticated-orcid":false,"given":"Massimiliano","family":"Pastena","sequence":"additional","affiliation":[{"name":"European Space Agency Directorate of Earth Observation Keplerlaan 1, 2201 Noordwijk, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,10]]},"reference":[{"key":"ref_1","unstructured":"(2020, September 29). 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