{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T15:13:29Z","timestamp":1776179609148,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2014,8,19]],"date-time":"2014-08-19T00:00:00Z","timestamp":1408406400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"funder":[{"name":"ESA DUE Tiger Innovator Project SHARE","award":["ESRIN\/Contract No. 19420\/05\/I-EC"],"award-info":[{"award-number":["ESRIN\/Contract No. 19420\/05\/I-EC"]}]},{"name":"ESA DUE Tiger Innovator Project TIGER NET","award":["ESRIN\/Contract No. 4000105732\/12\/I-NB"],"award-info":[{"award-number":["ESRIN\/Contract No. 4000105732\/12\/I-NB"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A surface soil moisture (SSM) product at a 1-km spatial resolution  derived from the Envisat Advanced Synthetic Aperture Radar (ASAR) Global Monitoring (GM) mode data was evaluated over the entire African continent using coarse  spatial resolution SSM acquisitions from the Advanced Microwave Scanning  Radiometer for Earth Observing System (AMSR-E) and the Noah land surface model  from the Global Land Data Assimilation System (GLDAS-NOAH). The evaluation  was performed in terms of relative soil moisture values (%), as well as anomalies  from the seasonal cycle. Considering the high radiometric noise of the ASAR GM  data, the SSM product exhibits a good ability (Pearson correlation coefficient  (R) = ~0.6 for relative soil moisture values and root mean square difference  (RMSD) = 11% when averaged to 5-km resolution) to monitor temporal soil  moisture variability in regions with low to medium density vegetation and yearly  rainfall &gt;250 mm. The findings agree with previous evaluation studies performed  over Australia and further strengthen the understanding of the quality of the  ASAR GM SSM product and its potential for data assimilation. Problems identified  in the ASAR GM algorithm over arid regions were explained by azimuthal effects.  Diverse backscatter behavior over different soil types was identified. The insights  gained about the quality of the data were used to establish a reliable masking  of the existing ASAR GM SSM product and the identification of areas where  further research is needed for the future Sentinel-1-derived SSM products.<\/jats:p>","DOI":"10.3390\/rs6087683","type":"journal-article","created":{"date-parts":[[2014,8,19]],"date-time":"2014-08-19T10:40:39Z","timestamp":1408444839000},"page":"7683-7707","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Seven Years of Advanced Synthetic Aperture Radar (ASAR) Global Monitoring (GM) of Surface Soil Moisture over Africa"],"prefix":"10.3390","volume":"6","author":[{"given":"Alena","family":"Dost\u00e1lov\u00e1","sequence":"first","affiliation":[{"name":"Department of Geodesy and Geoinformation, Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, Vienna 1040, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcela","family":"Doubkov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Geodesy and Geoinformation, Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, Vienna 1040, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"Sabel","sequence":"additional","affiliation":[{"name":"Department of Geodesy and Geoinformation, Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, Vienna 1040, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7356-7516","authenticated-orcid":false,"given":"Bernhard","family":"Bauer-Marschallinger","sequence":"additional","affiliation":[{"name":"Department of Geodesy and Geoinformation, Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, Vienna 1040, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7704-6857","authenticated-orcid":false,"given":"Wolfgang","family":"Wagner","sequence":"additional","affiliation":[{"name":"Department of Geodesy and Geoinformation, Vienna University of Technology, Gu\u00dfhausstra\u00dfe 27-29, Vienna 1040, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,8,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"141","DOI":"10.5194\/hess-14-141-2010","article-title":"Soil moisture active and passive microwave products: Intercomparison and evaluation over a Sahelian site","volume":"14","author":"Gruhier","year":"2010","journal-title":"Hydrol. 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