Terrænmodellering

Terrænmodellering, often translated as terrain modeling or digital elevation modeling, is the process of representing the three-dimensional shape of the Earth's surface. It involves creating digital representations of topography, which can be used in a wide range of applications. These models typically consist of a collection of data points with x, y, and z coordinates that define the elevation of specific locations.

Common methods for acquiring terrain data include aerial photogrammetry, where overlapping aerial photographs are used to create a 3D model, and LiDAR (Light Detection and Ranging), which uses laser pulses to measure distances and generate highly accurate elevation data. Satellite imagery and ground-based surveying are also utilized.

The resulting terrain models can take various forms, most notably Digital Elevation Models (DEMs), Digital Surface Models (DSMs), and Digital Terrain Models (DTMs). A DEM generally represents the bare earth surface, excluding vegetation and buildings, while a DSM includes these features. A DTM is a more specific representation of the terrain's surface itself, often derived from a DEM.

Applications of terrænmodellering are extensive. They are crucial in geographic information systems (GIS) for tasks like hydrological analysis, landslide susceptibility mapping, urban planning, and infrastructure design. In forestry and agriculture, they aid in understanding water flow and optimizing land use. Furthermore, terrain models are fundamental in computer graphics for creating realistic virtual environments, in video games, and in the film industry for visual effects.