The National Elevation Dataset (NED) is a new raster product developed by the U.S. Geological Survey (USGS) to provide national elevation data in a seamless format with consistent datum, elevation unit, and projection. The NED has a resolution of 1 arc-second (approximately 30 meters) for the conterminous United States, Hawaii, and Puerto Rico, and 2 arc-seconds for Alaska. Data corrections were made during the NED assembly process to minimize artifacts, permit edge matching, and fill sliver areas of missing data. The NED uses decimal meters as a consistent unit of measure, North American Datum 1983 as the horizontal datum, and a geographic projection. Older digital elevation models (DEM) were filtered to minimize artifacts. Artifact removal improves the quality of slope, shaded-relief, and synthetic drainage information. The NED is updated as higher resolution or higher quality data become available. The NED will incorporate new data from the USGS's 7.5-minute and 15-minute digital elevation products. For areas not yet covered, lower resolution DEM products were interpolated. The NED is documented using the Federal Geographic Data Committee's content standard for digital geospatial metadata. Spatially referenced metadata provides spatial context and links attributes of source datasets to their polygonal footprints. The NED is essential for earth science applications, including shaded-relief backgrounds, land cover classification, and synthetic drainage network analysis. The NED will be publicly available by late 2000 in the Spatial Data Transfer Standard (SDTS) raster profile. Data can be downloaded via the Internet or on standard distribution media. For more information, contact Customer Services at the EROS Data Center. Additional information is available at the USGS home page and other USGS product websites.The National Elevation Dataset (NED) is a new raster product developed by the U.S. Geological Survey (USGS) to provide national elevation data in a seamless format with consistent datum, elevation unit, and projection. The NED has a resolution of 1 arc-second (approximately 30 meters) for the conterminous United States, Hawaii, and Puerto Rico, and 2 arc-seconds for Alaska. Data corrections were made during the NED assembly process to minimize artifacts, permit edge matching, and fill sliver areas of missing data. The NED uses decimal meters as a consistent unit of measure, North American Datum 1983 as the horizontal datum, and a geographic projection. Older digital elevation models (DEM) were filtered to minimize artifacts. Artifact removal improves the quality of slope, shaded-relief, and synthetic drainage information. The NED is updated as higher resolution or higher quality data become available. The NED will incorporate new data from the USGS's 7.5-minute and 15-minute digital elevation products. For areas not yet covered, lower resolution DEM products were interpolated. The NED is documented using the Federal Geographic Data Committee's content standard for digital geospatial metadata. Spatially referenced metadata provides spatial context and links attributes of source datasets to their polygonal footprints. The NED is essential for earth science applications, including shaded-relief backgrounds, land cover classification, and synthetic drainage network analysis. The NED will be publicly available by late 2000 in the Spatial Data Transfer Standard (SDTS) raster profile. Data can be downloaded via the Internet or on standard distribution media. For more information, contact Customer Services at the EROS Data Center. Additional information is available at the USGS home page and other USGS product websites.