Application of SAR remote sensing data analysis in road emergency rescue operations during the 2023 Beijing flood disaster

This paper discusses a method to use SAR satellite remote sensing image data before and after the 2023 Beijing flood to extract the flood extent in time through appropriate data processing and band calculation, and provide basic data for postdisaster emergency response and road restoration. The principles and characteristics of SAR satellite remote sensing and the advantages of its application in flood response are discussed. The methods of downloading SAR and DEM data and the steps of data processing using ENVI SARScape software are introduced. Based on the experimental data, in order to accurately extract the flood range, the method of normalizing the image data of the two scenes before and after the flood is summarized, and the appropriate thresholds are set in the operation of each band.