{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T23:53:32Z","timestamp":1787356412289,"version":"3.56.0"},"reference-count":86,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,19]],"date-time":"2018-01-19T00:00:00Z","timestamp":1516320000000},"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>Microwave remote sensing has found numerous applications in areas affected by permafrost and seasonally frozen ground. In this study, we focused on data obtained by the Advanced Scatterometer (ASCAT, C-band) during winter periods when the ground is assumed to be frozen. This paper discusses the relationships of ASCAT backscatter with snow depth, air and ground temperature through correlations and the analysis of covariance (ANCOVA) to quantify influences on backscatter values during situations of frozen ground. We studied sites in Alaska, Northern Canada, Scandinavia and Siberia. Air temperature and snow depth data were obtained from 19 World Meteorological Organization (WMO) and 4 Snow Telemetry (SNOTEL) stations. Ground temperature data were obtained from 36 boreholes through the Global Terrestrial Network for Permafrost Database (GTN-P) and additional records from central Yamal. Results suggest distinct differences between sites with and without underlying continuous permafrost. Sites characterized by high freezing indices (&gt;4000 degree-days) have consistently stronger median correlations of ASCAT backscatter with ground temperature for all measurement depths. We show that the dynamics in winter-time backscatter cannot be solely explained through snow processes, but are also highly correlated with ground temperature up to a considerable depth (60 cm). These findings have important implications for both freeze\/thaw and snow water equivalent retrieval algorithms based on C-band radar measurements.<\/jats:p>","DOI":"10.3390\/rs10010142","type":"journal-article","created":{"date-parts":[[2018,1,22]],"date-time":"2018-01-22T04:51:13Z","timestamp":1516596673000},"page":"142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Dependence of C-Band Backscatter on Ground Temperature, Air Temperature and Snow Depth in Arctic Permafrost Regions"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4044-4792","authenticated-orcid":false,"given":"Helena","family":"Bergstedt","sequence":"first","affiliation":[{"name":"Department of Geoinformatics\u2013Z_GIS, University Salzburg, 5020 Salzburg, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon","family":"Zwieback","sequence":"additional","affiliation":[{"name":"Department of Geography, University of Guelph, Guelph, ON N1G 2W1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annett","family":"Bartsch","sequence":"additional","affiliation":[{"name":"b.geos, 2100 Korneuburg, Austria"},{"name":"Austrian Polar Research Institute, 1010 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4634-6413","authenticated-orcid":false,"given":"Marina","family":"Leibman","sequence":"additional","affiliation":[{"name":"Earth Cryosphere Institute Tyumen Scientific Centre SB RAS, PO Box 1230, 625000 Tyumen, Russia"},{"name":"International Institute of Cryology and Cryosophy, University of Tyumen, 6 Volodarskogo St., 625003 Tyumen, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2004","DOI":"10.1109\/TGRS.2007.898436","article-title":"Satellite microwave remote sensing of boreal and arctic soil temperatures from AMSR-E","volume":"45","author":"Jones","year":"2007","journal-title":"IEEE Trans. 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