Comparison of Vertical Accuracy of Open-Source Global Digital Elevation Models: A Case Study of Adama City, Ethiopia

DEM can be generated from a wide range of sources including land surveys, Photogrammetry, and Remote sensing satellites. SRTM 30m by The Shuttle Radar Topography Mission (SRTM), the Global Digital Elevation Model Advanced Spaceborne Thermal Emission Reflectance Radiometer (ASTER GDEM) global surface model called ALOS Worldview 3D 30 meter (AW3D30) Land Observing Satellite (ALOS) are satellite-based DEMs open-source datasets. This study aims to assess vertical accuracy ASTER GDEM2, 30m, over Ethiopia in area-Adama using DGPS points available accurate reference data. method used evaluate those ranges simple visual comparison relative absolute comparisons providing quantitative assessment (Statistical) that elevation differences between datasets result this showed better (having RMSE ± 4.63 m) closely followed which scored 5.25 m respectively. GDEM 2 least scoring 11.18 area. second was done analysis derived products such as slope drainage networks. also resulted quality for than GDEM.