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受限于洪灾时期的天气，用于洪灾评估的遥感数据多为雷达影像或者航拍数据，而众多夜间灯光和光学影像数据在评估洪灾时发挥的作用亟待进一步挖掘。本研究以7-8月份的阜阳为研究对象，基于Sentinel-1、Sentinel-2及Landsat 8等卫星数据，借助遥感大数据平台(GEE，Google Earth Engine)提取水体信息，并利用夜间灯光数据建立的夜间灯光总强度(TNL，Total Night-time Light)和综合灯光指数(CNLI，Compounded Night Light Index)来探讨水体变化与夜间灯光之间的关系，从而监测和评估洪灾动态。结果显示：(1)阜阳7-8月南部水体分布变化明显，特别是蒙洼蓄洪区水体面积明显增加，7月31日水体面积达到最大值323 km2，比洪灾前水体面积多出6倍，随后水体覆盖范围呈下降趋势，该趋势与王家坝开闸蓄洪和泄洪的时间对应。(2)基于夜间灯光指数TNL指数和CNLI指数对阜阳夜间灯光变化进行结合分析，发现灯光指数的变化趋势与水体的变化趋势相反，说明夜间灯光指数可以有效地反映出洪灾的变化过程。(3)对数据较完整的阜阳东部的水体及夜间灯光指数进行结合分析，进一步说明夜间灯光与水体数据均可用来监测洪灾。本研究以阜阳市今年的洪灾为例，拓展了夜间灯光数据和光学影像的应用范围，同时也证实了在经过严格的数据处理后，基于Sentinel-1的雷达影像、Sentinel-2和Landsat 8的光学影像等多源遥感数据均可有效监测洪灾的变化情况，在以后的洪灾监测中发挥重要的作用。
Limited by the weather during floods, the remote sensing data used for flood assessments are mostly radar images or aerial data, and the role of numerous night lights and optical image data in flood assessments needs to be further explored. This study took Fuyang from July to August as the research area, based on the monitoring data of Sentinel-1, Sentinel-2 and Landsat 8, and extracted water body information with the help of Google Earth Engine (GEE). This study used night light data (NPP-VIIRS DNB) to establish the Total Night-time Light (TNL) and Compounded Night Light (CNLI) to explore the relationship between water changes and night lights to monitor and evaluate the impact of floods. The results showed that: (1) The distribution of water bodies in the southern part of Fuyang changed significantly from July to August, especially the water bodies in the Mengwa Flood Diversion Project increased significantly. On July 31, the water body area reached the maximum of 323 km2, which was 6 times larger than the water body area before the flood. And then coverage of water bodies was declining. This trend corresponded to the time of flood storage and discharge of Wangjiaba gate. (2) The combined analysis of Fuyang night light index TNL index and CNLI index found that the change trend of the light index was opposite to that of the water body, indicating that the night light index can effectively reflect the changing process of flood disasters. (3) Analyzing the water body and night light index of eastern Fuyang with relatively complete data, it further showed that night light and water body data can be used to monitor floods. This research expands the application range of night light data and optical images, at the same time, it is also confirmed that after rigorous data processing, multi-source remote sensing data such as radar image based on sentinel-1, optical image based on sentinel-2 and Landsat 8 can effectively monitor the change of flood disaster and play an important role in flood monitoring in the future.