{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T17:34:17Z","timestamp":1777484057847,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2019,6,18]],"date-time":"2019-06-18T00:00:00Z","timestamp":1560816000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Key R&amp;D Program of Ministry of Science and Technology, China","award":["2017YFB1201500"],"award-info":[{"award-number":["2017YFB1201500"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41501360"],"award-info":[{"award-number":["41501360"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Spaceborne global navigation satellite system reflectometry (GNSS-R) data collected by the UK TechDemoSat-1 (TDS-1) satellite is applied to retrieve global lake levels for the first time. Lake levels of 351 global lakes (area greater than 500 km2 and elevation lower than 3000 m each) are estimated using TDS-1 Level 1b data over 2015\u20132017. Strong correlations (overall R2 greater than 0.95) are observed among lake levels derived from TDS-1 and other altimetry satellites such as CryoSat-2, Jason, and Envisat (the latter two are collected by Hydroweb), although with large root-mean-square error (RMSE) (tens of meters) mainly due to the fact that TDS-1 is not dedicated for altimetry measuring purpose. Examples of the Caspian Sea and the Poyang Lake show consistent spatial and temporal variations between TDS-1 and other data sources. The results in this paper provide supportive information for further application of GNSS-R constellations to measure altimetry of inland water bodies.<\/jats:p>","DOI":"10.3390\/rs11121438","type":"journal-article","created":{"date-parts":[[2019,6,19]],"date-time":"2019-06-19T02:42:46Z","timestamp":1560912166000},"page":"1438","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Spaceborne GNSS-R Observation of Global Lake Level: First Results from the TechDemoSat-1 Mission"],"prefix":"10.3390","volume":"11","author":[{"given":"Liwen","family":"Xu","sequence":"first","affiliation":[{"name":"Institute of Remote Sensing and GIS, School of Earth and Space Sciences, Peking University, Beijing 100871, China"},{"name":"Engineering Research Center of Earth Observation and Navigation (CEON), Ministry of Education, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei","family":"Wan","sequence":"additional","affiliation":[{"name":"Institute of Remote Sensing and GIS, School of Earth and Space Sciences, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiuwan","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Remote Sensing and GIS, School of Earth and Space Sciences, Peking University, Beijing 100871, China"},{"name":"Engineering Research Center of Earth Observation and Navigation (CEON), Ministry of Education, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0273-1336","authenticated-orcid":false,"given":"Siyu","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2390-2889","authenticated-orcid":false,"given":"Baojian","family":"Liu","sequence":"additional","affiliation":[{"name":"Institute of Remote Sensing and GIS, School of Earth and Space Sciences, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yang","family":"Hong","sequence":"additional","affiliation":[{"name":"Institute of Remote Sensing and GIS, School of Earth and Space Sciences, Peking University, Beijing 100871, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wan, W., Liu, B., Zeng, Z., Chen, X., Wu, G., Xu, L., Chen, X., and Hong, Y. 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