摘要
Digital Elevation Model (DEM) plays an important role in modeling floods. In data scarce developing countries, unavailability of high resolution topography and river cross-sections data are the prime limitations for simulating hydrodynamic models for modeling floods. In the present study, we assess the quality of Cartosat-1 DEMs in providing accurate river cross-sections and floodplain elevations; and hence their suitability in modeling floods. Cartosat-1 DEMs are prepared using Ground Control Points (GCP) of surveyed elevation and bias corrected Shuttle Radar Topography Mission (SRTM) elevation. Surveyed elevation based Cartosat-1 DEM is found to be of best quality while bias corrected SRTM elevation based Cartosat-1 DEM is found to be of reasonable quality on the basis of cross-section representation as well as elevation statistics. Cross-sections derived from the Cartosat-1 DEMs as well as surveyed cross-sections are later used independently in MIKE11 model for 1-dimensional flow modeling. Simulated water levels from models based on Cartosat-1 DEMs are compared graphically with the observed water levels. Modeling performance is also evaluated using different statistical performance criteria. Results show that the models based on Cartosat-1 DEM derived cross-sections perform similar to the model based on surveyed cross-sections. Study concludes that a reasonably accurate DEM, prepared from moderate survey in data scarce region, can be used for deriving requisite river cross-sections for hydrodynamic modeling.