VERTICAL ACCURACY COMPARISON OF ALOS AW3D30 DSM AND TRIGONOMETRIC SURVEY POINTS

摘要

Topographical information is fundamental to many geospatial related information and applications on Earth. Remote sensing satellites have the advantage in such fields because they are capable of global observation and repeatedly. One of the newest free of charge global digital surface model (DSM) is ALOS World 3D 30m mesh (AW3D30) and it is provided by Japan Aerospace Exploration Agency (JAXA). The AW3D30 version 1 released on May 2016 and on March 2017 the newer version 1.1 released with changes in specific areas. In Greece, the National Trigonometric Network established by the Hellenic Military Geographic Service (HMGS), the network includes 26,739 trigonometric control points but are not systematically maintained and many do not exist anymore. The trigonometric control points located in areas without vegetation, so the vegetation height does not influence the comparison. This paper calculates the vertical difference of the AW3D30 DSM and the trigonometric survey points of 1st, 2nd, 3rd, and 4th order. Also, a map identifying the areas with low and high height difference is presented.