ASTER
The ASTER GDEM, 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.
Older versions
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: https://lpdaac.usgs.gov/news/nasa-and-meti-release-aster-global-dem-version-3/
Difference between version 2 and 3
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: https://doi.org/10.5067/ASTER/ASTWBD.001
- Minimum water body detection size decreased from 1 square kilometer (km²) to 0.2 km².
- The removal of redistribution requirements, although the LP DAAC requests that you properly cite the data in your research. Pre-populated citations for the product can be found on the DOI Landing Page for the ASTER GDEM product under the "Citation" section. That page can be found here: https://doi.org/10.5067/ASTER/ASTGTM.003 (Note: The LP DAAC provides this information on DOI Landing Pages for all of the data products distributed by the LP DAAC.)
- More information about the Data Citation and Policies from the LP DAAC can be found here: https://lpdaac.usgs.gov/data/data-citation-and-policies/
Download Data
ASTER GDEM data are available via a variety of download methods.
- Direct download of individual files via the LP DAAC’s Data Pool: https://e4ftl01.cr.usgs.gov/ASTT/ASTGTM.003/
- Finding data directly in your study area via NASA’s Earthdata Search: https://search.earthdata.nasa.gov/search?q=ASTGTM
- Performing transformation services including subsetting, reprojecting, and mosaicking via the Application for Extracting and Exploring Analysis Ready Samples (AppEEARS)
- Visualize ASTER GDEM on the Earth via NASA’s Worldview: https://go.nasa.gov/3869Gml
Discussions
There have been several discussions about the ASTER data on the talk mailing list:
Questions ?
Have questions about ASTER GDEM data? Contact NASA's LP DAAC.
See also
On the wiki
Resources
- A list of publications that have previously used ASTER GDEM data.
- The ASTER GDEM User Guide. (PDF)
- General information about the Terra ASTER satellite sensor from the LP DAAC.
- Additional elevation products distributed by NASA’s LP DAAC.
- Additional Terra ASTER products distributed by NASA's LP DAAC.
- "Aster - Not Worth It Yet" by Gravitystorm - Published in 2010.
- Viewfinder Panoramas on ASTER - Published in 2009, updated in 2011.