期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2008
卷号：XXXVII Part B4
页码：1847-1852
出版社：Copernicus Publications
摘要：There are two major freely available global digital elevation datasets, known as GTOPO30 and SRTM. To know the accuracies of those data in global scale, relative evaluation of these data and validation with global scale are performed. We compared elevation values of GTOPO30 and SRTM 30 arc second datasets globally and found there are places in the world with more than kilometres differences in elevation especially in mountainous areas. Not only in mountainous areas, in planes also differed much. The values of SRTM are not always higher than that of GTOPO30. These differs exist randomly in global scale. Not only elevation, but also slope inclination and aspect of those data also very differ. To evaluate these differs, we develop a system, namely "Science DCP", which enables to validate these global DEMs at degree confluences, latitude and longitude integer degree intersections, in the world. ASTER DEM elevation data, field visit GPS elevation information from Degree Confluence Project, where in DCP were used as validation data. By using this system, we found that there exist distortions in the two datasets especially near 60-70 west longitudes. So we focused on 13°S 73°W where the values of these two datasets elevation differs about 600 m and where the values of these datasets much well. By using this system, user can easily validate global DEMs and the accuracy of global DEM will be improved
关键词：DEM; Validation; GTOPO30; SRTM; ASTER; Data Integration
