HIGH-RESOLUTION REMOTE SENSING ELEVATION MODELS FOR APPROPRIATE USE IN 3D LANDSCAPE VISUALISATION
C. Zenner1, E. Schmeer1, M. Wolff1, M. Jobst2
1 - Potsdam University, Germany
2 - Vienna University of Technology, Austria
To illustrate complex spatial facts, 3d visualization has gained major interest in science, economy, and publicity. The continuously improvement of the geometric resolution and accuracy of the underlying data enables 3d visualisations with an increasing quality.
Visualisations with a high level of detail result from high-resolution digital elevation models (DEM) as well as image data from remote sensing. The application of 3d visualisation as an instrument for the communication process facilitates the knowledge transfer and contributes to a better comprehension of spatial and time relevant issues.
The composition of virtual landscapes is based on the combination of an elevation model with overlaid pictorial data as well as additional geometric 3d models. Digital elevation models provide the foundation of virtual landscapes. Their quality depends on the accuracy of the elevation values as well as the grid dimension. To generate these virtual landscapes it is possible to apply two different types of elevation models: On the one hand a digital terrain model (DTM) which represents the shape of the Earth’s surface and on the other hand a digital surface model (DSM) which describes the topographic surface including all objects situated on the terrain.
Due to their different model characteristics, the DEMs suit for several thematic applications. Furthermore classification of different purposes offers various applications to visualise results which aim to explore or to represent information for professionals or the public.
For a detailed cartographic representation of the earth’s surface the scale plays a decisive role.
If using both models for visualisation with small and middle scales, the differences in the results might be disregarded. But when adapting to larger scales they are of special interest. In this context it is pointed out for which geo-scientific issues (e.g. visibility analysis, monitoring of flood situations or planning), target group the cartographic presentation method the particular model is suitable.
A direct comparison of both models for 3d visualisation is an often neglected topic. This paper will discuss the potentials and the deficits of both types of elevation models. To mark up their capability it will be necessary to compare by means of different thematic geo-spatial applications - for example in the field of urban and natural landscape.