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This layer of the 3D Elevation Program (3DEP) is 1/3 arc-second (approximately 10 m) resolution. The 1/3 arc-second 3DEP products and services are derived from diverse source data that are processed to a common coordinate system and unit of vertical measure. These data are distributed in geographic coordinates in units of decimal degrees, and in conformance with the North American Datum of 1983 (NAD 83). All elevation values are in meters and, over the continental United States, are referenced to the North American Vertical Datum of 1988 (NAVD88). The 1/3 arc-second 3DEP products and services provide seamless coverage of the conterminous United States, Hawaii, Puerto Rico, other territorial islands, and in limited areas of Alaska. The 1/3 arc-second 3DEP projects and services are available as pre-staged products tiled in 1 degree blocks in Erdas .img, ESRI arc-grid, and grid float formats. 3DEP products and services are updated continually as new data become available. All 3DEP data are in the public domain.