Flash Flood Hazard Mapping Using Landsat-8 Imagery, Ahp, And Gis In The Ngan Sau And Ngan Pho River Basins, North-Central Vietnam

Flash floods have been blamed for significant losses and destruction all around the world are widely, including Vietnam, a developing nation that has particularly hard hit by climate change. Therefore, flash flood hazards essential reducing risks. The topographic wetness index (TWI), altitude, slope, aspect, rainfall, land cover, normalized difference vegetation (NDVI), distances to rivers roads, flow length were used in this study create spatial database of ten exploratory factors influencing occurrence Ngan Sau Pho river basins (North-Central Vietnam). Subsequently, analytic hierarchy process (AHP) was applied calculate weights these factors. threat then mapped using GIS techniques. validation involved 151 inventory sites total. findings demonstrate (i) distance from (0.14) TWI greatest influence on flooding, whereas roads (0.06) NDVI found least influence; (ii) good conformity 84.8 percent between moderate very high levels hazard areas also discovered; (iii) covering 275 621.1 km 2 mainly detected along close main streams, respectively. These results demonstrated effectiveness techniques, AHP, Landsat-8 remote sensing data mapping.