Comparing a DTM created with ASTER data to GTOPO 30 and to one created from 1/50.000 topographic maps

摘要

In this paper we present the use of ASTER data for the creation of a Digital Terrain Model (DMT) of high accuracy. The area of study is Milos Island in the Aegean Sea. For the creation of the DTM we used an ASTER stereo-pair dating August 07, 2002. The images cover an area of 60X60 km. The images have been received in the near infrared (0,78-0,86 μm) part of the spectrum with a spatial resolution of 15m. We created a DMT a 30m-pixel size. Then we compared the DTM with the following DTM's: a) A GTOPO 30 DTM b) A DTM created from digitized contours of 1/50.000 scale topographic maps. We first made an optical comparison of the DTM's. Then, we proceed to statistical control of the histogram values of the three DTM's. From the first two controls we conclude that the GTOPO30 DTM is less accurate than the other two DTM's and we proceed in more detailed control only for the DTM from the digitized contours and for the DTM from the ASTER stereo-pair. We verified the DTM's accuracy using different points of well-known elevation. All the results demonstrated that DTM's derived from ASTER data have better accuracy than the other two DTM's.