The U.S. Geological Survey (USGS) and the National Geospatial-Intelligence Agency (NGA) have released an updated and more accurate global elevation model that pulls data from Digital Terrain Elevation Data (DTED®) from the Shuttle Radar Topography Mission (SRTM); Canadian elevation data; SPOT 5 Reference 3D data; data from NASA’s Ice, Cloud, and land Elevation Satellite (ICESat); and updated Antarctica and Greenland terrain models. This new elevation data called Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010), replaces the thirty year old GTOPO30 terrain model.
GMTED2010 is a suite of seven raster data products: minimum elevation, maximum elevation, mean elevation, median elevation, standard deviation of elevation, systematic subsample, and breakline emphasis. The spatial resolution of GMTED2010 ranges from 30, 15 and 7.5 arc-seconds (approximately 1 kilometer, 500 meters and 250 meters, respectively). The data was created by aggregating the highest resolution data available in a given geographic area. At this spatial resolution, the data can be appropriate for GIS analysis at the regional, continental, and global level.
GTOPO30 is georefenced to the World Geodetic System 1984 (WGS 84) horizontal datum and, in most cases, to the Earth Gravitational Model 1996 (EGM96) geoid as the vertical datum.