|
ASTER Digital Elevation Model – AST14DEM-Absolute
Version 2.00, October 2001
This is the final version of the Absolute Digital Elevation Model (DEM) product created from ASTER Level 1A bands 3N and 3B, and is a VALIDATED product. This product is an absolute digital elevation model from ASTER Level 1A bands 3N and 3B. This product requires input of ground control points (GCPs) by the requestor.
Table of Contents
1. Where to get detailed information on this product
2. How to report problems
3. Description of this version
* Product Quality
* Problems and limitations
4. Version history
1. Where to get detailed information on this product
There are several sources of information that users will find useful:
* Product descriptive information. EDC DAAC provided information on DEM products
http://edcdaac.usgs.gov/aster/ast14dem.html
* ASTER Digital Elevation Models Algorithm Theoretical Basis Document. Describes the algorithm used to create the product. Available at
http://eospso.gsfc.nasa.gov/eos_homepage/for_scientists/atbd/viewInstrument.php?instrument=24
* ASTER Higher-Level Product User Guide. Describes each of the ASTER Higher Level products in detail, including definitions of each metadata attribute and the science data fields. Available at the ASTER website (see below).
* US ASTER Website. Describes the ASTER instrument, how to obtain data, the various data products that are available, the activities of the US ASTER Science Team, etc.
http://asterweb.jpl.nasa.gov/
* Level 1 product information. Because the Digital Elevation Model product is derived from a Level 1 product, understanding the L1 products is useful.
Level 1 ATBD available at
http://eospso.gsfc.nasa.gov/eos_homepage/for_scientists/atbd/viewInstrument.php?instrument=24
Level 1 User Guide available at
http://www.science.aster.ersdac.or.jp/en/index.html
2. How to report problems
To report a problem with the product, please send mail to edc@eos.nasa.gov
or call EDC DAAC User Services at (605) 594-6116 or (866) 573-3222 (toll-free)
3. Description of this version
Digital Elevation Model V2.00
Changes
Final Release
Product Quality
Validation of the DEM product has been undertaken by the US Geological Survey, Jet Propulsion Laboratory, and University of Georgia. The production of absolute DEMs appears to be satisfactory. For the data sets evaluated thus far, differences of the means between reference DEMs and ASTER DEMs range from +4 m to +27 m.
Problems and limitations
The software introduces occasional small pits and hills as artifacts, particularly in flat areas. In areas of clouds, water, or featureless terrain (dry lakes, snow, etc.), correlations fail, and the data values are reported as –150.
The geocoding information of the DEM in HDF-EOS format can only currently be ingested by one commercial image processing package. In most cases, the user must manually georeference the DEM using coordinates found in the metadata files. Alternatively, a GEO-TIFF version of the DEM is produced and provided to the requestor on an FTP site.
Projection and datum information is missing from the metadata fields; this problem will be solved soon. The information is currently inserted in the metadata file as a text field.
4. Version History
Initial Release
|
