Digital Terrain Model (DTM)

A Digital Terrain Model (DTM) is a three-dimensional digital representation of the bare ground surface, excluding vegetation, buildings, and other surface objects. It captures the topographic features of the Earth’s surface using elevation data points arranged in a regular grid or as triangulated irregular networks (TINs).

DTMs are derived from various remote sensing technologies such as LiDAR (Light Detection and Ranging), aerial photogrammetry, or satellite-based radar systems. The raw data is processed to remove above-ground features and interpolate a continuous surface representing ground elevations.

DTMs provide vital information for understanding natural landforms, slopes, and hydrological flow. Unlike Digital Surface Models (DSMs), which include all surface features (e.g., trees, buildings), DTMs represent only the ground level, making them particularly useful for geological and engineering applications.

In industry, DTMs are applied in land-use planning, flood risk assessment, environmental modelling, infrastructure design, and excavation volume calculations. Their precision enables accurate simulations, cross-section analyses, and compatibility with BIM and GIS platforms for integrated spatial planning.

See also: Geo Radaring