Coastal Digital Elevation Models (DEMs)

Digital elevation models (DEMs) of U.S. and other coasts that typically integrate ocean bathymetry and land topography. The DEMs support NOAA's mission to understand and predict changes in Earth's environment, and conserve and manage coastal and marine resources to meet our Nation's economic, social, and environmental needs. NOAA's National Centers for Environmental Information (NCEI) has built many of these models, and also distributes DEMs on behalf of other NOAA offices, as well national and international partners. Bathymetric, topographic, and shoreline data used in DEM development come from a variety of sources, including NOAA's National Ocean Service (NOS) and NCEI, the U.S. Geological Survey (USGS), the U.S. Army Corps of Engineers (USACE), and the Federal Emergency Management Agency (FEMA), as well as other federal, state, and local government agencies, academic institutions, and private companies. The DEMs are referenced to a variety of vertical tidal datums, typically mean high water (MHW) or North American Vertical Datum of 1988 (NAVD 88), and usually a horizontal datum of North American Datum of 1983 (NAD 83) or World Geodetic System 1984 (WGS84). DEM cell sizes range from high-resolution models (1/9 to 1/3 arc-second; ~3 to 10 meters) that support coastal inundation studies, to regional models (roughly 3 to 24 arc-seconds) that extend farther offshore, to global models (1 arc-minute; ~2 km).