Using ASTER GDEM and SRTM digital elevation models to generate contour lines over rugged terrain of Makkah

In this paper the medium scale resolution data of ASTER GDEM (Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model) and SRTM (Shuttle Radar Topography Mission) data, which is the most significant space surveys of earth ever undertaken, are used to generate contour lines for the studied area of rugged terrain of Makkah, Saudi Arabia using PCI Geomatica 10.3 software. The range of study sites represents various terrain types in arid environments. Then, the comparison between ASTER GDEM and SRTM for the height distribution and differences of horizontal transect lines were plotted and analyses. The results show that ASTER GDEM that has been generated has mean absolute error up to 22.767 m (compared to SRTM) with 139 m of minimum and maximum height difference and -19 m of mean error in the study area.