Detailed Evaluation of DEM Interpolation Methods in GIS Using DGPS Data

Digital Elevation Model (DEM) is a numerical representation of topography and is made up of equal-sized grid cells, each with a value of elevation. The DEMs that were generated from the spot heights by general interpolation techniques namely Inverse Distance Weighted (IDW), Kriging, Topo to Raster, Natural Neighbor (NN) and Spline approaches have been compared. The relative performance of each method depends on various ground parameters and spatial distribution of sampling points. In this research investigation, performance of the above mentioned five interpolation methods have been evaluated by generating and validating the DEM from Differential Global Positioning System (DGPS) data in the ArcGIS software. With respect to our sample observations´ spatial distribution and densities, the investigation results have shown that IDW method is giving better performance in plane and mild slope area, Natural Neighbor provides better performance in steep slope and whole area as compared to other methods.