Using SRTM DEM, Landsat ETM+ images and a distributed rainfall-runoff model to define inundation hazard maps on urban canyons

摘要

Landsat 7 ETM+ images, a SRTM Digital Elevation Model (DEM) and a distributed Rainfall-Runoff Model were used to generate inundation hazard maps on urban canyons. Return periods were calculated and interpolated by means of ordinary kriging to generate 24 hours precipitation maps. These maps were disaggregated to 15 minutes precipitation maps using empirical relations. The land cover map was obtained by a supervised classification of a Landsat 7 ETM+ image. Flow directions and flow accumulations and a topographic position map were obtained by processing the SRTM DEM to route the obtained effective precipitation along the drainage network. The topographic map was used to define the geographic extension of the drainage lines. We believe that our approach to estimate channel dimensions of each segment in the drainage system without field measurements is an interesting contribution of remote sensing and geomatics to the field of flood hazard mapping.