AsterDEM
ASTER Digital Elevation Model
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AsterDEM |
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Data Set Characteristics
Data Type DEM
Swatch Area = ~60 km x 60 km
Dimensions = 2500 rows x 2500 columns
Input Image Resolution = 15 meters
Output Image Resolution = 30 meters
Projection = UTM
Datum = WGS84 (except USA)
File Size = ~25 MB
Data Type = 32-bit real
Product Description
The ASTER Digital Elevation Model is a product generated from a pair of ASTER Level 1A images. The Aster L1A input includes bands 3N (nadir) and 3B (aft-viewing) from the Visible Near Infra-Red telescope's along-track stereo data that is acquired in the spectral range of 0.78 to 0.86 microns.
Aster_DEMs can be generated either with or without Ground Control Points (GCPs). These DEMs have an absolute horizontal and vertical accuracy of up to 7 meters with appropriate GCPs and up to 10 meters without GCPs.
An Absolute DEM is created with GCPs that are supplied by an end-user who has requested the product. Alternatively, a Relative DEM can also be generated without GCPs.
Aster_DEMs meet map accuracy standards for scales from 1:50,000 to 1:250,000 and can be used to derive absolute slope and slope aspect which is good up to 5 degrees over a horizontal distance of over 100 meters.
Aster_DEMs are well suited to produce Digital Terrain Models (DTMs).
3-D Digital
Elevation Model of the Orange River
(border between South
Africa and Namibia)
Naming and Format Description
The typical file name e.g. ASTER_DEM20030311100358, contains only information relative to the processing date and time of the DEM granule i.e. in this case 2003/03/11 at 10:03:58. All ASTER data products are stored in a specific implementation of Hierarchical Data Format called HDF-EOS (extension .hdf). However AsterDEM data is also made available in the more common elevation TIF format.
Software Requirements
Advanced GIS software is required for reading the HDF format. Most GIS software is able to use the TIF format. Global Mapper can read both HDF and TIF format. Oziexplorer cannot read either.
Currently Madmappers is generating a dataset in a common binary format which can be readily used by Oziexplorer.
Additional details regarding the instrument, data products etc. can be accessed from: