{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T09:13:01Z","timestamp":1771578781668,"version":"3.50.1"},"reference-count":87,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2022,6,29]],"date-time":"2022-06-29T00:00:00Z","timestamp":1656460800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Delaware Strategic Initiative research","award":["#2103854"],"award-info":[{"award-number":["#2103854"]}]},{"name":"University of Delaware Strategic Initiative research","award":["#2103836"],"award-info":[{"award-number":["#2103836"]}]},{"name":"Software Ecosystem for kNowledge diScOveRY-a data-driven framework for soil moisture applications","award":["#2103854"],"award-info":[{"award-number":["#2103854"]}]},{"name":"Software Ecosystem for kNowledge diScOveRY-a data-driven framework for soil moisture applications","award":["#2103836"],"award-info":[{"award-number":["#2103836"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Soil moisture is an important parameter that regulates multiple ecosystem processes and provides important information for environmental management and policy decision-making. Spaceborne sensors provide soil moisture information over large areas, but information is commonly available at coarse resolution with spatial and temporal gaps. Here, we present a modular spatial inference framework to downscale satellite-derived soil moisture using terrain parameters and test the performance of two modeling methods (Kernel-Weighted K-Nearest Neighbor &lt;KKNN&gt; and Random Forest &lt;RF&gt;). We generate monthly and weekly gap-free spatial predictions on soil moisture at 1 km using data from the European Space Agency Climate Change Initiative (ESA-CCI; version 6.1) over two regions in the conterminous United States. RF was the method that performed better in cross-validation when comparing with the reference ESA-CCI data, but KKNN showed a slightly higher agreement with ground-truth information as part of independent validation. We postulate that more heterogeneous landscapes (i.e., high topographic variation) may be more challenging for downscaling and predicting soil moisture; therefore, moisture networks should increase monitoring efforts across these complex landscapes. Future opportunities for development of modular cyberinfrastructure tools for downscaling satellite-derived soil moisture are discussed.<\/jats:p>","DOI":"10.3390\/rs14133137","type":"journal-article","created":{"date-parts":[[2022,6,29]],"date-time":"2022-06-29T22:43:28Z","timestamp":1656542608000},"page":"3137","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Downscaling Satellite Soil Moisture Using a Modular Spatial Inference Framework"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5716-0959","authenticated-orcid":false,"given":"Ricardo M.","family":"Llamas","sequence":"first","affiliation":[{"name":"Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19716, USA"}]},{"given":"Leobardo","family":"Valera","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, TN 37996, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0258-6861","authenticated-orcid":false,"given":"Paula","family":"Olaya","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, TN 37996, USA"}]},{"given":"Michela","family":"Taufer","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, TN 37996, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6829-5333","authenticated-orcid":false,"given":"Rodrigo","family":"Vargas","sequence":"additional","affiliation":[{"name":"Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19716, USA"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,29]]},"reference":[{"key":"ref_1","unstructured":"Bond, P. 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