{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T05:43:30Z","timestamp":1771047810499,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2023,8,8]],"date-time":"2023-08-08T00:00:00Z","timestamp":1691452800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U21A20108"],"award-info":[{"award-number":["U21A20108"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["722403\/067\/004"],"award-info":[{"award-number":["722403\/067\/004"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Double First-Class Project Cultivation Special Project\u2014Key Technology for Intelligent Equipment and Intelligent Processing of Spatiotemporal Information","award":["U21A20108"],"award-info":[{"award-number":["U21A20108"]}]},{"name":"Double First-Class Project Cultivation Special Project\u2014Key Technology for Intelligent Equipment and Intelligent Processing of Spatiotemporal Information","award":["722403\/067\/004"],"award-info":[{"award-number":["722403\/067\/004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In this paper, we investigated the vertical distribution characteristics of surface soil moisture based on ISMN (International Soil Moisture Network) multilayer in situ data (5, 10, and 20 cm; 2, 4, and 8 in) and performed comparisons between the in situ data and four microwave satellite remote sensing products (SMOS L2, SMOS-IC, SMAP L2, and SMAP L4). The results showed that the mean soil moisture difference between layers can be \u22120.042~\u22120.024 (for the centimeter group)\/\u22120.067~\u22120.044 (for the inch group) m3\/m3 in negative terms and 0.020~0.028 (for the centimeter group)\/0.036~0.040 (for the inch group) m3\/m3 in positive terms. The surface soil moisture was found to have very significant stratification characteristics, and the interlayer difference was close to or beyond the SMOS and SMAP 0.04 m3\/m3 nominal retrieval accuracy. Comparisons revealed that the satellite retrievals had a higher correlation with the field measurements of 5 cm\/2 in, and SMAP L4 had the smallest difference with the in situ data. The mean difference caused by using 10 cm\/4 in and 20 cm\/8 in in situ data instead of the 5 cm\/2 in data could be about \u22120.019~\u22120.018\/\u22120.18~\u22120.015 m3\/m3 and \u22120.026~\u22120.023\/\u22120.043~\u22120.039 m3\/m3, respectively, meaning that there would be a potential depth mismatch in the data validation.<\/jats:p>","DOI":"10.3390\/rs15163930","type":"journal-article","created":{"date-parts":[[2023,8,8]],"date-time":"2023-08-08T12:38:59Z","timestamp":1691498339000},"page":"3930","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["The Characterization of the Vertical Distribution of Surface Soil Moisture Using ISMN Multilayer In Situ Data and Their Comparison with SMOS and SMAP Soil Moisture Products"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0923-0681","authenticated-orcid":false,"given":"Na","family":"Yang","sequence":"first","affiliation":[{"name":"School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China"}]},{"given":"Feng","family":"Xiang","sequence":"additional","affiliation":[{"name":"College of Computer Science and Technology, Henan Polytechnic University, Jiaozuo 454000, China"}]},{"given":"Hengjie","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6814","DOI":"10.1109\/TGRS.2020.3026384","article-title":"Soil Moisture Retrieval Depth of P- and L-Band Radiometry: Predictions and Observations","volume":"59","author":"Shen","year":"2021","journal-title":"IEEE Trans. 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