Maps of Malaysia

Japan’s Ministry of Economy, Trade and industry (METI) and NASA released a GDEM on 29 June 2009. This GDEM (Global Digital Elevation Model) was created by stereo-correlating the 1.3 million scene ASTER VNIR archive, covering the Earth’s land surface between 83N and 83S latitudes from the year 2000 onwards. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) is an imaging instrument flying on Terra, a satellite launched in December 1999 as part of NASA's Earth Observing System (EOS).

The GDEM covers land surfaces between 83°N and 83°S with estimated accuracies of 20 meters at 95% confidence for vertical data and 30 meters at 95% confidence for horizontal data. By contrast the horizontal resolution for the SRTM data is 90m.

The raw data is available for free from http://asterweb.jpl.nasa.gov/gdem.asp

At the moment, only one version has been released.

Version 1

Version 1 of the ASTER-GDEM is not perfect. Areas persistently covered by clouds are badly distorted. Although there are few of these areas because the data was collected over years, these distortions are quite jarring and compare badly with SRTM v4 which appears on casual inspection to be free of artefacts.

It is obviously much more detailed though as attested by its size in megabytes (more than double). The mountains are a lot more intricate.

Completed maps

Malaysia, Singapore and Brunei (including portions of Kalimantan and Sumatra) 10m contours v1.00

Malaysia, Singapore and Brunei 10m contours v1.01

Thailand and some neighbours, 10m contours v1.00

Future maps

I intend to do a map for South East Asia at some (distant) point, starting with Thailand. A map of SEA with comparable detail as the current Malaysia map would be rather large and tedious to compile. Perhaps I will wait for a future more refined version of the ASTER-GDEM.