These metadata describe the 1-degree digital elevation model holdings of the USGS for the conterminous United States. The standard DEM consists of a regular array of elevations cast on a designated coordinate projection system. The DEM data are stored as a series of profiles in which the spacing of the elevations along and between each profile is in regular whole number intervals. The normal orientation of data is by columns and rows. Each column contains a series of elevations ordered from south to north with the order of the columns from west to east.
Coverage is for the United States.
DEM's can be used as source data for digital orthophotos, and, as layers in geographic information systems, for earth science analysis. DEM's can also serve as tools for volumetric analysis, for site location of towers, or for drainage basin delineation. 1-degree DEM's have rows and columns which are based on the geographic coordinate system. The use of this system results in a rectangular DEM which shares a common edge and therefore duplicate points with other adjacent 1-degree DEM's. Acknowledgement of the U.S. Geological Survey would be appreciated in products derived from these data.