The ASTER GDEM covers land surfaces between 83°N and 83°S and comprises 22,912 1° by 1° tiles. Tiles that contain at least 0.01% land area are included. The ASTER GDEM is distributed in GeoTIFF file format with Geographic latitude/longitude coordinates and a 1 arc-second (30 m) grid of elevation postings. It is referenced to the WGS84/EGM96 geoid. Studies to validate and characterize the ASTER GDEM confirm that accuracies for this global product are 20 meters at 95% confidence for vertical data and 30 meters at 95% confidence for horizontal data.
Compared to Version 2, Version 3 has a decrease in elevation void area due to the increase of ASTER stereo image data and improved process, and a decrease in water area anomaly data due to using new global water body data to be described later.
The United States National Aeronautics and Space Administration (NASA) and the Ministry of Economy, Trade, and Industry (METI) of Japan today jointly released Version 3 of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM). The ASTER GDEM is available at no charge to users worldwide via electronic download from Japan Space Systems and from NASA’s Land Processes Distributed Active Archive Center (LP DAAC).
N.B. With this release, an additional global product is now available: the ASTER Water Bodies Database (ASTWBD). This raster product identifies all water bodies as either ocean, river, or lake. Each GDEM tile has a corresponding Water Body tile. This data product provides the only water mask covering nearly the entire surface of the Earth.