Accuracy Evaluation of SRTM (used in Google Earth) by Comparison with National Topographic maps (1:50,000) in North of Iraq

Abstract

Digital Elevation Models (DEM) of a region can be generated from stereopairs of satellite images , enables the work to improve decision-making, take faster and more informed action based on geospatial information, but some times these data may be unavailable or expensive for students to use it in a mapping and preliminary design. Today Google Earth Enterprise helps organizations with amazing speed, full context, imagery and other geospatial data DEM with incredible resource for downloading topo data, makes that information accessibleto all employees who need access via data with no cost. Google earth Geospatial data DEM it been lunched from (SRTM) NASAs Shuttle Radar Topography Mission. The aim of our study is to assess the quality of the GE-SRTM-DEM derived from the X-SAR system and comparing it with selected national topographical maps for north of Iraq with scale 1:50,000 . An important aspect of the study is to be able to conclude on the real relevancy of the GE-SRTM product compared to the already existing products, for instance is it to be considered as a new global topographic reference or should it be only limited to some applicationssuch as GIS-projects, hydrological, mapping, even it can be used in preliminary design stage for projects.