In support of military applications, the National Imagery and Mapping Agency (NIMA) has developed standard digital datasets (Digital Terrain Elevation Data (DTED) which is a uniform matrix of terrain elevation values which provides basic quantitative data for systems and applications that require
The LandScan data set is a worldwide population databasecompiled on a 30in X 30in latitude/longitude grid.
Online Resource of GIS datasets
Most images on this CD-ROM are LANDSAT browse images, used to determine image quality and cloud cover. These images are subsampled at a ratio 16 to 1 and have an effective resolution of 480 meters (approximately 3/10 of a mile per pixel.
This database contains extensive cartographicbasemap data for the world at a scale of 1:3 million.It includes cartographic, index, and statistical information suitablefor a wide range of mapping, reference, and analytical application