Learn more about Elevation
The elevation of a geographic location is its height above a fixed reference point, often the mean sea level. Elevation is mainly used when referring to points on the Earth's surface, while altitude is used for points in the air, such as an aircraft. Less commonly, elevation is measured, using the center of the Earth as the reference point. Due to equatorial bulge, there is debate whether the summits of Mt. Everest or Chimborazo are at the higher elevation, as Chimborazo is further from the Earth's center while Mt. Everest is higher above mean sea level.
 Maps and GIS
In a Geographic Information System (GIS), digital elevation models (DEM) are commonly used to represent the surface (topography) of a place, through a raster (grid) dataset of elevations. Digital terrain models are another way to represent terrain in GIS.
The elevation of a mountain usually refers to its summit. The elevation of a hill also refers to the summit. A valley's elevation is usually taken from the lowest point but is often taken all over the valley.
 See also
 External links
- U.S. Geological Survey
- Geographical Survey Institute
- Downloadable ETOPO2 Raw Data Database (2 minute grid)
- Downloadable ETOPO5 Raw Data Database (5 minute grid)de:Höhe über dem Meeresspiegel