Accuracy of Digital Elevation Model According to Spatial Resolution

There are many kinds of DEM (Digital Elevation Model) generation methods such as a stereomatching from aerial photograph or satellite image, an interferometry from SAR data and an interpolation of topographic maps. On the other hand, we can use some accomplished DEMs. For example, NGDC NOAA offers global land one-km base elevation (GLOBE). And USGS offers Digital Chart of the World that has elevation information also. Each DEM has various grid size and various elevation accuracy. DEM is indispensable for many analyses such as topographic feature extraction, runoff analysis, slope stability analysis, landscape analysis and so on. We must consider which accuracy is appropriate for any analyses. Therefore, study of DEM accuracy is very important. In this study, an accuracy of DEM according to spatial resolution will be evaluated. We prepared a various grid size of DEMs. The DEMs will be used for topographical analysis, slope stability analysis and runoff analysis. After that, results from resampled rough DEM will be compared with result from original DEM. A relationship between spatial resolution and DEM accuracy will be concluded.