<oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"><dc:creator>World Wildlife Fund (WWF)</dc:creator><dc:description>This raster layer is a void-filled digital elevation model (DEM) of North America at 15 arc-seconds resolution. Elevation is expressed in meters and referenced to the WGS84 EGM96 geoid. The primary data s ource of HydroSHEDS is the digital elevation model of the Shuttle Radar Topography Mission. SRTM elevation data were obtained by a specially modified radar system that flew onboard the Space Shuttle Endeavor during an 11-day mission in February of 2000. Regions of no-data (voids), specifically mountainous regions, or those over large water bodies prevented the production of reliable elevation data. The existence of no-data in the DEM causes significant problems for deriving hydrological products, which require continuous flow surfaces. Therefore, a void-filling procedure has been applied to provide a continuous DEM for HydroSHEDS.</dc:description><dc:description>The goal of developing HydroSHEDS was to generate key data layers to support regional and global watershed analyses, hydrological modeling, and freshwater conservation planning at a quality, resolution and extent that had previously been unachievable.</dc:description><dc:description>This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.</dc:description><dc:format>ArcGRID</dc:format><dc:identifier>https://purl.stanford.edu/wj406qc5431</dc:identifier><dc:language>eng</dc:language><dc:publisher>U.S. Geological Survey</dc:publisher><dc:rights>Public</dc:rights><dc:subject>Digital elevation models</dc:subject><dc:subject>Elevation</dc:subject><dc:subject>Imagery and Base Maps</dc:subject><dc:title>North America: Void-filled digital elevation model, 15s resolution, 2009</dc:title><dc:type>Datasets</dc:type><dc:coverage>North America</dc:coverage><dc:date>2009</dc:date><dc:contributor>Stanford</dc:contributor></oai_dc:dc>