摘要
依据1:25万地形图DEM对中国西北部高山高原地区来自美国ESRI和NASA的两种SRTM数据进行了质量评价.结果表明两种SRTM高程数据与地形图DEM有很高的一致性.两类SRTM数据大约有38%的栅格单元绝对高程误差小于10 m,58%以上误差小于20 m,90%以上误差小于49 m,99%以上误差小于92 m,99.9%以上误差小于143 m.在地势平坦的高原盆地、宽谷区,高程误差小于±5 m.湖泊水体区域分别存在显著的正负高程误差.冰川、山地针叶林和沙漠地区的高程偏差均呈峰值,位于-20～0 m的正态分布,极少数栅格单元正负偏差超过100 m.总体而言,SRTM数据具有较高的数据质量.
The quality of SRTM3 DEM data for alpine and plateau areas in the northwestern China was evaluated against DEM data extracted from 1：250 000 scale topographic maps. These SRTM data were obtained from an ESRI ArcGIS 9.2 software package and NASA＇s Jet Propulsion Laboratory website, respectively. It is shown that these two data sources provide a greater location precision than a DEM based on topographic maps. The ESRI SRTM data have about 38% of raster units with less than 10 m absolute elevation error, 58% about 〈20 m, 90% about 〈49 m, 99% about 〈92 m, and 99.9% about 〈143 m compared with the topographic maps. In relatively low and flat basins, as well as the wide valleys on the plateau, the absolute elevation error is less than ±5 m. Elevation errors in glacial, deciduous forest and desert settings present a normal Gaussian distribution with all the peaks at -20 to 0 m, and few raster units with absolute errors of more than 100 m. The higher quality SRTM data will be valuable for research in many fields.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2008年第6期1-7,共7页
Journal of Lanzhou University(Natural Sciences)
