{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T01:05:42Z","timestamp":1773450342499,"version":"3.50.1"},"reference-count":56,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,20]],"date-time":"2021-12-20T00:00:00Z","timestamp":1639958400000},"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>On 20 July 2021, parts of China\u2019s Henan Province received the highest precipitation levels ever recorded in the region. Floods caused by heavy rainfall resulted in hundreds of casualties and tens of billions of dollars\u2019 worth of property loss. Due to the highly dynamic nature of flood disasters, rapid and timely spatial monitoring is conducive for early disaster prevention, mid-term disaster relief, and post-disaster reconstruction. However, existing remote sensing satellites cannot provide high-resolution flood monitoring results. Seeing as spaceborne global navigation satellite system-reflectometry (GNSS-R) can observe the Earth\u2019s surface with high temporal and spatial resolutions, it is expected to provide a new solution to the problem of flood hazards. Here, using the Cyclone Global Navigation Satellite System (CYGNSS) L1 data, we first counted various signal-to-noise ratios and the corresponding reflectivity to surface features in Henan Province. Subsequently, we analyzed changes in the delay-Doppler map of CYGNSS when the observed area was submerged and not submerged. Finally, we determined the submerged area affected by extreme precipitation using the threshold detection method. The results demonstrated that the flood range retrieved by CYGNSS agreed with that retrieved by the Soil Moisture Active Passive (SMAP) mission and the precipitation data retrieved and measured by the Global Precipitation Measurement mission and meteorological stations. Compared with the SMAP results, those obtained by CYGNSS have a higher spatial resolution and can monitor changes in the areas affected by the floods over a shorter period.<\/jats:p>","DOI":"10.3390\/rs13245181","type":"journal-article","created":{"date-parts":[[2021,12,21]],"date-time":"2021-12-21T04:23:47Z","timestamp":1640060627000},"page":"5181","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":49,"title":["Using CYGNSS Data to Map Flood Inundation during the 2021 Extreme Precipitation in Henan Province, China"],"prefix":"10.3390","volume":"13","author":[{"given":"Shuangcheng","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Geology Engineering, Chang\u2019an University, Xi\u2019an 710054, China"},{"name":"State Key Laboratory of Geo-Information Engineering, Xi\u2019an 710054, China"}]},{"given":"Zhongmin","family":"Ma","sequence":"additional","affiliation":[{"name":"College of Geology Engineering, Chang\u2019an University, Xi\u2019an 710054, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8054-7449","authenticated-orcid":false,"given":"Zhenhong","family":"Li","sequence":"additional","affiliation":[{"name":"College of Geology Engineering, Chang\u2019an University, Xi\u2019an 710054, China"},{"name":"Big Data Center for Geosciences and Satellites, Chang\u2019an University, Xi\u2019an 710054, China"},{"name":"Key Laboratory of Western China\u2019s Mineral Resources and Geological Engineering, Ministry of Education, Xi\u2019an 710054, China"}]},{"given":"Pengfei","family":"Zhang","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]},{"given":"Qi","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Geology Engineering, Chang\u2019an University, Xi\u2019an 710054, China"},{"name":"Earth Observation Research Group, Institute of Space Sciences (ICE, CSIC), 08290 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9101-4007","authenticated-orcid":false,"given":"Yang","family":"Nan","sequence":"additional","affiliation":[{"name":"GNSS Research Center, Wuhan University, Wuhan 430079, China"}]},{"given":"Jingjiang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Urban Meteorology, China Meteorological Administration, Beijing 100089, China"}]},{"given":"Shengwei","family":"Hu","sequence":"additional","affiliation":[{"name":"College of Geology Engineering, Chang\u2019an University, Xi\u2019an 710054, China"}]},{"given":"Yuxuan","family":"Feng","sequence":"additional","affiliation":[{"name":"College of Geology Engineering, Chang\u2019an University, Xi\u2019an 710054, China"}]},{"given":"Hebin","family":"Zhao","sequence":"additional","affiliation":[{"name":"College of Geology Engineering, Chang\u2019an University, Xi\u2019an 710054, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,20]]},"reference":[{"key":"ref_1","unstructured":"(2021, November 02). 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