Least Squares Matching for Comparison of Digital Terrain Models and its Application Potential for the Brazilian models and the SRTM model

Digital terrain models are being used for planning and hydrological applications, but also for visualization and many tasks more. For all applications it is necessary to know the quality of the model, because it has an impact on the quality of the decisions that are drawn from the terrain model applications. In this paper we present a method that is suitable for comparing two terrain models to each other. Vertical, but also horizontal displacement of terrain features can be found automatically, which are systematic errors and are in the main focus of this paper. However, random errors can be quantified, too. This method allows establishing a vector field of differences between two models, measuring the deviation from one to the other. These deviations are a measure of quality of one model against the other. Emphasis will be put on comparing terrain model from NASA's Shuttle Radar Topographic Mission to terrain models of known quality in Brazil.