Accuracy assessment of GDEM, SRTM, and DLR-SRTM in Northeastern China

Abstract

This paper compares the accuracy of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM), Shuttle Radar Topography Mission (SRTM) C-band and German Aerospace Centre (DLR)-SRTM X-band digital elevation models (DEMs) with the Ziyuan 3 (ZY-3) stereoscopic DEM and ground control points (GCPs). To date, the horizontal error of these DEMs has received little attention in accuracy assessments. Using the ZY-3 DEM as reference, this study examines (1) the horizontal offset between the three DEMs and the reference DEM using the normalised cross-correlation method, (2) the vertical accuracy of those DEMs using kinematic GPS data and (3) the relationship between the three DEMs and the reference ZY-3 DEM. The results show that the SRTM and DLR-SRTM have greater vertical accuracy after applying horizontal offset correction, whereas the vertical accuracy of the ASTER GDEM is less than the other two DEMs. These methods and results can be useful for researchers who use DEMs for various applications.

Keywords:

• Digital elevation model (DEM)
• Co-registration
• Horizontal shift
• Accuracy assessment
• ZY-3 DEM

Acknowledgements

This work was supported by the China Geological Survey Project under Grant 1212011220106, the National Natural Science Foundation of China under Grants 41001248 and 41301026, the Youth Science and Technology Morning Program of Wuhan under Grant 2013070104010027 and the Fundamental Research Funds for the Central Universities under Grants 106112013cdjzr160005, CUG100706 and CUG130106.