ASTER/TERRA DEM (Trentino, Italy)



The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is a 14-channel visible to thermal-infrared sensor that was launched as part of the Earth Observing System (EOS) Terra payload on 18 December 1999. ASTER is an on-demand instrument.

The ASTER data set contains topographic information derived from the along-track, 15 m ASTER optical stereo data acquired in near-infrared bands 3N and 3B. These high spatial resolution DEMs (up to 7 m absolute horizontal and vertical accuracy with appropriate ground control, and up to 10 m relative accuracy without ground control) can be used to derive absolute slope and slope aspect good to 5 degrees over horizontal distances of more than 100 m. ASTER DEMs should meet 1:50,000 to 1:250,000 map accuracy standards ([1]:112). An autocorrelation approach using proprietary software at the LP-DAAC produces DEMs from Level-1A or 1B digital stereo pairs. Both absolute DEMs as well as relative DEMs are produced. For an absolute DEM Ground Control Points (GCPs) must be provided for the area of interest. A relative DEM is generated by using only the satellite ephemeris data and is horizontally not nearly as accurate as the absolute DEM.

In summary, two types of ASTER-DEM are available:

To find out the type of ASTER-DEM, gdalinfo may be used:
gdalinfo ASTER_DEM20020827134235.hdf | grep DEMType
GRASS can directly import ASTER-DEM (import into a UTM/WGS84 location).


[1] Jet Propulsion Laboratories, ASTER Higher-Level Product User Guide, JPL D-20062, May 2001, PDF

See also

ASTER DEM Coverage Map


ASTER data products

ASTER Digital Elevation Model

Markus Neteler 2002 - 2003
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