A new method of generating grid DEM from contour lines

Digital elevation model (DEM) data are widely used in many research areas such as hydrological analysis and soil erosion models. To generate an accurate DEM is very important to the validity of such researches. Generating DEM from contour lines is now a main method to get grid DEM. In the implementation of GIS software, usually the elevation of a cell with only one contour line (SVC) is simply assigned with the contour line elevation when discretizing vector contour lines. But most of the time, the elevation of the contour line can´t characterize the elevation of the SVC accurately. In this paper, we choose different resolutions (cell size) to investigate the frequency of SVCs during DEM generating and the errors created by simply assigning their elevations with the contour line elevations. A new method is given, in which we analyze the spatial relationship between the SVC and the corresponding contour line. And at last, a zone of Inner Mongolia is chosen to prove the validity of the new method.