Each tile is distributed in the UTM Zone in which it lies. All bare earth elevation values are in meters and are referenced to the North American Vertical Datum of 1988 (NAVD88). The spatial reference used for tiles of the one-meter DEM within the conterminous United States (CONUS) is Universal Transverse Mercator (UTM) in units of meters, and in conformance with the North American Datum of 1983 (NAD83). One-meter DEM surfaces are seamless within collection projects, but, not necessarily seamless across projects. USGS standard one-meter DEMs are produced exclusively from high resolution light detection and ranging (lidar) source data of one-meter or higher resolution. The elevations in this DEM represent the topographic bare-earth surface. Scientists and resource managers use 3DEP data for hydrologic modeling, resource monitoring, mapping and visualization, and many other applications.
This is a tiled collection of the 3D Elevation Program (3DEP) and is one meter resolution.The 3DEP data holdings serve as the elevation layer of The National Map, and provide foundational elevation information for earth science studies and mapping applications in the United States.
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