{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T02:34:42Z","timestamp":1780454082739,"version":"3.54.1"},"reference-count":58,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2016,4,28]],"date-time":"2016-04-28T00:00:00Z","timestamp":1461801600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Water level (WL) and water volume (WV) of surface-water bodies are among the most crucial variables used in water-resources assessment and management. They fluctuate as a result of climatic forcing, and they are considered as indicators of climatic impacts on water resources. Quantifying riverine WL and WV, however, usually requires the availability of timely and continuous in situ data, which could be a challenge for rivers in remote regions, including the Mekong River basin. As one of the most developed rivers in the world, with more than 20 dams built or under construction, Mekong River is in need of a monitoring system that could facilitate basin-scale management of water resources facing future climate change. This study used spaceborne sensors to investigate two dams in the upper Mekong River, Xiaowan and Jinghong Dams within China, to examine river flow dynamics after these dams became operational. We integrated multi-mission satellite radar altimetry (RA, Envisat and Jason-2) and Landsat-5\/-7\/-8 Thematic Mapper (TM)\/Enhanced Thematic Mapper plus (ETM+)\/Operational  Land Imager (OLI) optical remote sensing (RS) imageries to construct composite WL time series with enhanced spatial resolutions and substantially extended WL data records. An empirical relationship between WL variation and water extent was first established for each dam, and then the combined long-term WL time series from Landsat images are reconstructed for the dams. The R2 between altimetry WL and Landsat water area measurements is &gt;0.95. Next, the Tropical Rainfall Measuring Mission (TRMM) data were used to diagnose and determine water variation caused by the precipitation anomaly within the basin. Finally, the impact of hydrologic dynamics caused by the impoundment of the dams is assessed. The discrepancy between satellite-derived WL and available in situ gauge data, in term of root-mean-square error (RMSE) is at 2\u20135 m level. The estimated WV variations derived from combined RA\/RS imageries and digital elevation model (DEM) are consistent with results from in situ data with a difference at about 3%. We concluded that the river level downstream is affected by a combined operation of these two dams after 2009, which has decreased WL by 0.20 m\u00b7year\u22121 in wet seasons and increased WL by 0.35 m\u00b7year\u22121 in dry seasons.<\/jats:p>","DOI":"10.3390\/rs8050367","type":"journal-article","created":{"date-parts":[[2016,4,28]],"date-time":"2016-04-28T10:25:55Z","timestamp":1461839155000},"page":"367","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Assessment of the Impact of Reservoirs in the Upper Mekong River Using Satellite Radar Altimetry and Remote Sensing Imageries"],"prefix":"10.3390","volume":"8","author":[{"given":"Kuan-Ting","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Civil Engineering, National Central University, 32001 Taoyuan, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3581-076X","authenticated-orcid":false,"given":"Kuo-Hsin","family":"Tseng","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering, National Central University, 32001 Taoyuan, Taiwan"},{"name":"Center for Space and Remote Sensing Research, National Central University, 32001 Taoyuan, Taiwan"},{"name":"Institute of Hydrological and Oceanic Sciences, National Central University, 32001 Taoyuan, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9378-4067","authenticated-orcid":false,"given":"C.","family":"Shum","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Geodesy and Earth\u2019s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, 430077 Wuhan, China"},{"name":"Division of Geodetic Science, School of Earth Sciences, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1725-4405","authenticated-orcid":false,"given":"Chian-Yi","family":"Liu","sequence":"additional","affiliation":[{"name":"Center for Space and Remote Sensing Research, National Central University, 32001 Taoyuan, Taiwan"},{"name":"Department of Atmospheric Sciences, National Central University, 32001 Taoyuan, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3449-995X","authenticated-orcid":false,"given":"Chung-Yen","family":"Kuo","sequence":"additional","affiliation":[{"name":"Department of Geomatics, National Cheng Kung University, 70101 Tainan, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ganming","family":"Liu","sequence":"additional","affiliation":[{"name":"Division of Geodetic Science, School of Earth Sciences, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuanyuan","family":"Jia","sequence":"additional","affiliation":[{"name":"Division of Geodetic Science, School of Earth Sciences, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kun","family":"Shang","sequence":"additional","affiliation":[{"name":"Division of Geodetic Science, School of Earth Sciences, Ohio State University, Columbus, OH 43210, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,4,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0022-1694(01)00396-1","article-title":"Modelling the Mekong: Hydrological simulation for environmental impact studies","volume":"253","author":"Kite","year":"2001","journal-title":"J. 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