Monday, November 21, 2011

HowTo Mosaic ASTER Global Digital Elevation Model (GDEM)

A second version of ASTER GDEM was released in Oct. 17 2011 by The Ministry of Economy, Trade and Industry of Japan (METI) and the National Aeronautics and Space Administration (NASA). The GDEM is in a 30m pixel resolution and 1x1 degree tiles. The data is distributed as zipped GeoTIFF files. When a larger than 1x1 deg. DEM is needed for Interferometry processing, you can use my GDEM.py script available from my script page. This python script will need a system with pylab and PIL python modules.

Simply:
Download the GDEM zipped files (see here on how to do that).
Unzip the zip files in the working directory.
The working directory should contain sub-directories containing the GeoTIFF files.
Run the script giving -h for help or the final DEM name as arguments.
The Final DEM is aimed for using as DEM in ROI-PAC interferometry processing.
If a -g is added as an argument, the produced DEM will be suitable for interferometric processing using Gamma software.