The Global Multi-resolution Terrain Elevation Data (GMTED) 2010 dataset is the elevation dataset of choice for global and continental scale applications. GMTED2010 is the result of a joint development effort between the U.S. Geological Survey (USGS) and the National Geospatial-Intelligence Agency (NGA). GMTED2010 is a major improvement in consistency and vertical accuracy over GTOPO30.
Starting with ENVI 5.1, the software installation includes the GMTED2010 dataset for the mean elevation aggregation method at 30 arc seconds spatial resolution in numerically lossless JPEG2000 format. ENVI provides the GMTED2010 dataset as a convenience for users who need a digital elevation model in their data visualization or image processing workflows. However, for best results, you should use a DEM raster with a higher resolution than GMTED2010. Many DEM products are available from the U.S. Geological Survey National Map and Download Platform or EarthExplorer.Use the File > Open World Data > Elevation (GMTED2010) menu option to open it.
The default paths are as follows:
- Windows: C:\Program Files\INSTALL_DIR\ENVIxx\data\GMTED2010.jp2
- Linux: /usr/local/INSTALL_DIR/ENVIxx/data/GMTED2010.jp2
- Mac: /Applications/INSTALL_DIR/ENVIxx/data/GMTED2010.jp2
A world file (GMTED2010.j2w) and projection file (GMTED2010.prj) accompany the DEM.
RPC Orthorectification and Image Registration workflows automatically use this dataset as the default DEM.
To replace the GMTED2010 dataset in the ENVI software installation with this higher spatial resolution version, overwrite the GMTED2010.jp2, GMTED2010.j2w, and GMTED2010.prj files in the appropriate path listed above (may require administrative privileges).
Reference:
Danielson, J., and D. Gesch. "Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010)." U.S. Geological Survey Open-File Report 2011-1073 (2011), 26 p. http://pubs.usgs.gov/of/2011/10pdf/of2011-1073.pdf