Topography
Overview
Topography is the arrangement of the natural and artificial physical features of an area, including its terrain, elevation, and landforms. In GIS, topography is typically represented through elevation data such as contour lines, digital elevation models (DEMs), and hillshade renderings.
Key Concepts
Elevation is the height above a reference surface (usually mean sea level). Relief is the difference between highest and lowest elevations in an area. Slope is the steepness or gradient of the terrain surface. Aspect is the compass direction that a slope faces. Contour lines are lines connecting points of equal elevation. Landform is a natural feature of the Earth’s surface (mountain, valley, plain).
Representation Methods
| Method | Description |
|---|---|
| Contour lines | Isolines of equal elevation |
| Digital Elevation Model (DEM) | Raster grid of elevation values |
| Digital Terrain Model (DTM) | Bare-earth elevation (no vegetation/buildings) |
| TIN (Triangulated Irregular Network) | Vector-based elevation model |
| Hillshade | Shaded relief visualization |
Appendix
Created: 2025-12-13 | Modified: 2025-12-13
See Also
- Geographic Information System (GIS)
- Cartography
- Digital Elevation Model (DEM)
- United States Geological Survey (USGS)