Elevation

About Elevation

Elevation histogram of the surface of the Earth – approximately 71% of the Earth's surface is covered with water.

The 'elevation' of a geographic location is its height above a fixed reference point, often the mean sea level. Elevation, or 'geometric height', is mainly used when referring to points on the Earth's surface, while 'altitude' or 'geopotential height' is used for points above the surface, such as an aircraft in flight or a spacecraft in orbit.
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.

Contents
Maps and GIS
Topography
See also
External links

Maps and GIS


A topographical map is the main type of map used to depict elevation, often through use of contour lines.
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.
To determine elevation of a place, it must be surveyed, in reference to a ground control point.
Part of a topographic map of Haleakala (Hawaii), showing elevation.

Topography


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



★ altitude

★ geodesy

★
★ geodesy of North America

★
★
★ Sea Level Datum of 1929 later National Geodetic Vertical Datum of 1929 (NGVD 29)

★
★
★ North American Vertical Datum of 1988 (NAVD 88)

★ List of highest mountains

★ List of highest towns by country

★ physical geography

★ summit (topography)

★ summit eminence

★ topographic isolation

★ topographic prominence

★ topographical map

★ topography

External links



★ U.S. National Geodetic Survey website

★
★ Geodetic Glossary @ NGS

★
★ NGVD 29 to NAVD 88 online elevation converter @ NGS

★ United States Geological Survey website

★ Geographical Survey Institute

★ Downloadable ETOPO2 Raw Data Database (2 minute grid)

★ Downloadable ETOPO5 Raw Data Database (5 minute grid)

★ bivouac.com Canadian Mountain Encyclopedia

★ peakbagger.com

★ peaklist.org

★ peakware.com World Mountain Encyclopedia

★ summitpost.org

This article provided by Wikipedia. To edit the contents of this article, click here for original source.