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The Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM) Version 3 (ASTGTM) provides a global digital elevation model (DEM) of land areas on Earth at a spatial resolution of 1 arc second (approximately 30 meter horizontal posting at the equator). The geographic coverage of the ASTER GDEM extends from 83° North to 83° South latitude. The data are broken up into 1° by 1° tiles, with each tile distributed in GeoTIFF / Cloud Optimized GeoTIFF (COG) format and projected on the 1984 World Geodetic System (WGS84)/1996 Earth Gravitational Model (EGM96) geoid. Each of the 22,912 tiles in the collection contain at least 0.01% land area. ASTER GDEM data are now freely available in the public domain.  

There have been two previous versions of ASTER GDEM data. The latest version, ASTER GDEM Version 3, was released on August 5, 2019. NASA’s Land Processes Distributed Active Archive Center (LP DAAC), the distributor of the data, released a news announcement with more information about the data and the differences between Version 2 and Version 3. The news announcement can be found here:

Notable differences between the Version 2 and Version 3 product include:

  • Expansion of acquisition coverage to increase the amount of cloud free input scenes from about 1.5 million in Version 2 to about 1.88 million scenes in Version 3.  
  • A decrease in elevation void area due to an increase of ASTER Stereo image data and improved processing
  • A decrease in water area anomaly data due to a new global water body data product called the “ASTER Water Bodies Dataset (ASTWBD).” This raster identifies all water bodies as either ocean, river, or lake. Each GDEM tile has a corresponding  ASTWBD tile. This data product provides the only water mask covering nearly the entire surface of the Earth.  More information on this product can be found here:  
    • Minimum water body detection size decreased from 1 square kilometer (km²) to 0.2 km².

ASTER GDEM data are available via a variety of download methods.

  • Performing transformation services including subsetting, reprojecting, and mosaicking via the Application for Extracting and Exploring Analysis Ready Samples (AppEEARS)  

There have been several discussions about the ASTER data on the talk mailing list:

Have questions about ASTER GDEM data? Contact NASA's LP DAAC.

See also