Digital Elevation Model (DEM)

Définition

A Digital Elevation Model (DEM) is a digital representation of the topography of a land surface or terrain. It is a digital 3D model of the Earth's surface that captures the elevation or height of each point on the surface, as well as the slope, aspect, and other terrain characteristics.

DEM is commonly created using remote sensing techniques, such as LiDAR (Light Detection and Ranging) or photogrammetry, which use laser or aerial images to measure the elevation of the terrain. DEMs can be used in a variety of applications, such as in environmental modeling, land management, flood risk assessment, and urban planning.

Here are some examples of how DEMs are used:

  1. Hydrology: DEMs are used to model the flow of water in rivers and streams, as well as to identify watersheds and wetlands.
  2. Terrain analysis: DEMs are used to study the land surface and its characteristics, such as slope, aspect, and curvature. This information is used in geology, forestry, and agriculture, among other fields.
  3. Urban planning: DEMs are used to model and visualize the built environment, such as buildings and roads, as well as to assess the suitability of a location for different types of development.
  4. Natural resource management: DEMs are used to map and monitor the distribution of natural resources, such as forests, minerals, and water resources.

Overall, DEMs are an important tool for understanding and managing the Earth's surface, and are used in a wide range of fields to study and plan for the impacts of natural and human-made changes on the environment.