{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:04:29Z","timestamp":1787029469975,"version":"3.56.0"},"reference-count":57,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2014,9,17]],"date-time":"2014-09-17T00:00:00Z","timestamp":1410912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Knowledge of surface hydrology is essential for many applications, including studies that aim to understand permafrost response to changing climate and the associated feedback mechanisms. Advanced remote sensing techniques make it possible to retrieve a range of land-surface variables, including radar retrieved soil moisture (SSM). It has been pointed out before that soil moisture retrieval from satellite data can be challenging at high latitudes, which correspond to remote areas where ground data are scarce and the applicability of satellite data of this type is essential. This study investigates backscatter variability other than associated with changing soil moisture in order to examine the possible impact on soil moisture retrieval. It focuses on issues specific to SSM retrieval in the Arctic, notably variations related to tundra lakes. ENVISAT Advanced Synthetic Aperture Radar (ASAR) Wide Swath (WS, 120 m) data are used to understand and quantify impacts on Metop (AAdvanced Scatterometer (ASCAT, 25 km) soil moisture retrieval during the snow free period. Sites of interest are chosen according to ASAR WS availability, high or low agreement between output from the land surface model ORCHIDEE and ASCAT derived SSM. Backscatter variations are analyzed with respect to the ASCAT footprint area. It can be shown that the low model agreement is related to water fraction in most cases. No difference could be detected between periods with floating ice (in snow off situation) and ice free periods at the chosen sites. The mean footprint backscatter is however impacted by partial short term surface roughness change. The water fraction correlates with backscatter deviations (relative to a smooth water surface reference image) within the ASCAT footprint areas (R = 0.91)<\/jats:p>","DOI":"10.3390\/rs6098718","type":"journal-article","created":{"date-parts":[[2014,9,17]],"date-time":"2014-09-17T10:53:17Z","timestamp":1410951197000},"page":"8718-8738","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Assessing Seasonal Backscatter Variations with Respect to Uncertainties in Soil Moisture Retrieval in Siberian Tundra Regions"],"prefix":"10.3390","volume":"6","author":[{"given":"Elin","family":"H\u00f6gstr\u00f6m","sequence":"first","affiliation":[{"name":"Research Group Remote Sensing, Department of Geodesy and Geoinformation (GEO), Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, A-1040 Vienna, Austria"},{"name":"Research Group Remote Sensing, Austrian Polar Research Institute, Vienna University, Althanstra\u00dfe 14, A-1090 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Trofaier","sequence":"additional","affiliation":[{"name":"Research Group Remote Sensing, Department of Geodesy and Geoinformation (GEO), Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, A-1040 Vienna, Austria"},{"name":"Research Group Remote Sensing, Austrian Polar Research Institute, Vienna University, Althanstra\u00dfe 14, A-1090 Vienna, Austria"},{"name":"Scott Polar Research Institute, University of Cambridge, Lensfield Road, Cambridge, CB2 1ER, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isabelle","family":"Gouttevin","sequence":"additional","affiliation":[{"name":"Institut National de Recherche en Sciences et Technologies pour l'Environnement et l'Agriculture, Unit\u00e9 de Recherche Hydrologie-Hydraulique, 5 rue de la Doua, CS 70077, F-69626 Villeurbanne Cedex, France"},{"name":"CRYOS School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Federale de Lausanne, Batiment GR, Station 2, CH-1015 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annett","family":"Bartsch","sequence":"additional","affiliation":[{"name":"Research Group Remote Sensing, Department of Geodesy and Geoinformation (GEO), Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, A-1040 Vienna, Austria"},{"name":"Research Group Remote Sensing, Austrian Polar Research Institute, Vienna University, Althanstra\u00dfe 14, A-1090 Vienna, Austria"},{"name":"Department of Geography, Ludwig-Maximilians-Universit\u00e4t M\u00fcnchen, Luisenstra\u00dfe 37 ,D-80333 Munich, Germany"},{"name":"IFFB Geoinformatik-Z GIS, Universit\u00e4t Salzburg, Hellbrunner Str, 35, A-5020 Salzburg, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,9,17]]},"reference":[{"key":"ref_1","unstructured":"IPCC. 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