Comparison of DEMS derived from USGS DLG, SRTM, a statewide photogrammetry program, ASTER GDEM and LiDAR: implications for change detection

Many digital elevation models (DEMs) now exist, enabling quantitative assessments of topographic change through DEM subtraction. However, many of these DEMs are inherently different - their source data, preprocessing, and interpolation procedures introduce varying amounts of error, which are partially correlated with the local topographic situation (e.g. slope, aspect, and elevation of any given location). Understanding of these differences and potential errors is necessary prior to change detection analysis in order to incorporate the inherent uncertainties into the analysis of topographic change. This study evaluated available DEMs in the Mud 7.5 ' United States Geological Survey (USGS) topographic quadrangle in West Virginia, USA. We compare DEMs derived from the USGS digital line graphs (DLGs), the Shuttle Radar Topography Mission (SRTM), a statewide photogrammetric DEM, and the Advanced Spaceborne Thermal Emission and Reflection (ASTER) Global DEM v2, to a LiDAR DEM. Using the LiDAR data as a reference (RMSE 0.12m), the USGS DLG and the SAMB showed low RMSE, while the SRTM and GDEM exhibited high RMSE and a systematic negative bias.