{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T18:08:08Z","timestamp":1785348488626,"version":"3.55.0"},"reference-count":49,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,13]],"date-time":"2022-11-13T00:00:00Z","timestamp":1668297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Belgian Federal Science Policy Office (BELSPO)","award":["SR\/00\/376, 2019\u20132021"],"award-info":[{"award-number":["SR\/00\/376, 2019\u20132021"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>We investigated the possibilities of improving hydrological simulations by assimilating radar backscatter observations from the advanced scatterometer (ASCAT) in the hydrological model SCHEME using a calibrated water cloud model (WCM) as an observation operator. The WCM simulates backscatter based on soil moisture and vegetation data and can therefore be used to generate observation predictions for data assimilation. The study was conducted over two Belgian catchments with different hydrological regimes: the Demer and the Ourthe catchment. The main differences between the two catchments can be summarized in precipitation and streamflow levels, which are higher in the Ourthe. The data assimilation method adopted here was the ensemble Kalman filter (EnKF), whereby the uncertainty of the state estimate was described via the ensemble statistics. The focus was on the optimization of the EnKF, and possible solutions to address biases introduced by ensemble perturbations were investigated. The latter issue contributes to the fact that backscatter data assimilation only marginally improves the overall scores of the discharge simulations over the deterministic reference run, and only for the Ourthe catchment. These performances, however, considerably depend on the period considered within the 5 years of analysis. Future lines of research on bias correction, the data assimilation of soil moisture and backscatter data are also outlined.<\/jats:p>","DOI":"10.3390\/rs14225740","type":"journal-article","created":{"date-parts":[[2022,11,14]],"date-time":"2022-11-14T04:24:10Z","timestamp":1668399850000},"page":"5740","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Assimilation of Backscatter Observations into a Hydrological Model: A Case Study in Belgium Using ASCAT Data"],"prefix":"10.3390","volume":"14","author":[{"given":"Pierre","family":"Baguis","sequence":"first","affiliation":[{"name":"Royal Meteorological Institute of Belgium, Avenue Circulaire 3, B-1180 Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0722-5600","authenticated-orcid":false,"given":"Alberto","family":"Carrassi","sequence":"additional","affiliation":[{"name":"Department of Meteorology and NCEO, University of Reading, Reading RG6 7BE, UK"},{"name":"Department of Physics and Astronomy \u201cAugusto Righi\u201d, University of Bologna, 40126 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emmanuel","family":"Roulin","sequence":"additional","affiliation":[{"name":"Royal Meteorological Institute of Belgium, Avenue Circulaire 3, B-1180 Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phane","family":"Vannitsem","sequence":"additional","affiliation":[{"name":"Royal Meteorological Institute of Belgium, Avenue Circulaire 3, B-1180 Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sara","family":"Modanesi","sequence":"additional","affiliation":[{"name":"Research Institute for Geo-Hydrological Protection, National Research Council, Via della Madonna Alta 126, 06128 Perugia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hans","family":"Lievens","sequence":"additional","affiliation":[{"name":"Department of Environment, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8042-9792","authenticated-orcid":false,"given":"Michel","family":"Bechtold","sequence":"additional","affiliation":[{"name":"Department of Earth and Environmental Sciences, KU Leuven, Celestijnenlaan 200E, B-3001 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6743-7122","authenticated-orcid":false,"given":"Gabrielle","family":"De Lannoy","sequence":"additional","affiliation":[{"name":"Department of Earth and Environmental Sciences, KU Leuven, Celestijnenlaan 200E, B-3001 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4869","DOI":"10.1029\/2018GL077193","article-title":"Exploiting soil moisture, precipitation, and streamflow observations to evaluate soil moisture\/runoff coupling in land surface models","volume":"45","author":"Crow","year":"2018","journal-title":"Geophys. 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