A first assessment of Aster GDEM tiles for absolute accuracy, relative accuracy and terrain parameters

The Global DEM (GDEM) product is being generated from Advanced Space borne Thermal Emission and Reflection Radiometer (ASTER) data by Japan´s Ministry of Economy, Trade, and Industry (METI) and the National Aeronautics and Space Administration (NASA). It is a snapshoot of the reflective surface of the earth during the time period of the mission, and is about 100 times more detailed than existing global elevation data, such as GTOPO 30[1] and GLOBE[2] and nine times more detailed than the existing SRTM[3, 4]. Up to now, only limited evaluation has been performed of the GDEM dataset. From what is known about the processing methodology it is expected that the Aster GDEM contains a significant number of anomalies that prevents immediate use for a wide range of applications.