Hillshaded grid based on 70 m cell digital elevation model (DEM)

Hillshade created by Ecotrust based on the U.S. Geological Survey ( USGS) Digital Elevation Model (DEM) data files. DEMs are digital representations of cartographic information in a raster form. DEMs consist of a sampled array of elevations for a number of ground positions at regularly spaced intervals. The 70m DEM is equivalent to the 15-minute DEM data which corresponds to the USGS 1:63,360-scale topographic quadrangle map series of Alaska by unit size.