Accuracy Assessment of Srtm-Dem Using GpsMeasurments and Gis Techniques

Abstract

Shuttle Radar Topographic Mission (SRTM) has created datasets of globalelevations that is freely available for modeling and environmental applications. Theglobal availability (almost 80% of the Earth surface) of SRTM data providesbaseline information for geospatial applications such as mapping, hydrology,navigation, GIS applications, and reconnaissance. Assessment of the accuracy ofSRTM requires regional studies involving points with known elevations at higherlevel of precision than the SRTM, usually measured with Global PositioningSystem (GPS).This study based on datasets collected with a differential GPS system in differentlocations in Iraq. These measurements were corrected with differential methods toreach to sub – centimeter accuracy. Statistical analysis included estimation ofabsolute errors by Root Mean Square Error (RMSE), Standard Deviation (SD).RMSE was found as (5.15m) for Iraq and the SD was (3.93). This is higher thanthe standard SRTM-DEM accuracy which is (16m)