Accuracy Assessment of SRTM DEM, ASTER GDEM, AW3D30 DSM, and TanDEM-X 90 m DEM Based on Runway Elevation Data

Purpose: DEM is widely used in the analysis of spatio-temporal correlation and clustering, and plays an important role in geographic big data mining. To assist researchers in selecting the most suitable dataset according to the application requirements, a comparative analysis of the accuracy of the highest resolution or the latest version of four freely available DEMs was conducted in this study.[Method: 19 relatively uniformly distributed runway elevation data were used as reference data, and line-based method was adopted to quantitatively analyze DEM elevation accuracy. Based on elevation datum unification, the elevation error at each checkpoint can be calculated. And the error statistical indicators were selected based on the error distribution.Conclusion: The experimental results show that the errors of various DEMs do not follow normal distribution. For ASTER GDEM with the lowest accuracy, there has relatively evident offsets exist in elevation. The accuracy of SRTM DEM and AW3D30 DSM are relative higher. And then, TanDEM-X 90 m has the smallest error statistical indicators and steepest probability density function, indicating its high accuracy and overall sound representation of the topographic relief.