An evaluation of EU-DEM in comparison with ASTER GDEM, SRTM and contour-based DEMs over the Eastern Mecsek Mountains

Abstract

The availability of global coverage digital surface models (like ASTER GDEM or SRTM) and the variation of fused models based on these (like EU-DEM) still has a great impact on scientific researches, as they provides a fairly good base dataset with a low production time and expenses. However, validation reports of the initial DSMs convinced different characteristics and errors, thus it is essential to examine these height datasets prior to application. A verifying process for EU-DEM is more important, because it has been published without a formal validation. Although the base of the EU-DEM was a corrected ASTER GDEM dataset, the visual assessment and the error statistics suggest more similarity to the SRTM DSM. This study goes further than just identifying the errors, it attempts to moderate or correct the height differences. For this reason altering the false values of the land cover and filtering the occurring noise was implemented. The geomorphometric analyses carried out as part of the verification methods propose each improved model as potential base for geomorphological studies, if they meet the certain eff ective resolution requirements.

Keywords

• eu-dem
• aster gdem
• srtm
• denoising
• geomorphometry
• open source gis