elevation, vertical distance from a datum plane, usually mean sea level to a point above the earth. Often used synonymously with altitude, elevation is the height on the earth's surface and altitude, the height in space above the surface. The elevation of a feature is calculated through such surveying techniques as trigonometric triangulation and aerial photogrammetry. Elevation is represented by using contours of equal elevation lines, three-dimensional computer graphics representation, or molded three-dimensional plastic models.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.