Encyclopedia > Digital elevation model

  Article Content

Digital elevation model

A digital elevation model' (DEM) is a representation of the topography of the Earth in digital format, that is, by coordinates and numerical descriptions of altitude. DEMs are used often in geographic information systems.

A free DEM of the whole world called GTOPO30 (30 arcsecond resolution, approx. 1km) is available (see Link below). It can be used to generate maps such as in the International gliding online contest (http://www.onlinecontest.org/). Several other DEMs are available, but the better they are, the more they cost.

External links

All Wikipedia text is available under the terms of the GNU Free Documentation License

  Search Encyclopedia

Search over one million articles, find something about almost anything!
  Featured Article
Quadratic formula

... it a perfect square trinomial of the form x2 + 2xy + y2. Since "2xy" in this case is (b/a)x, we must have y = b/(2a), so we add the square of b/(2a) to both sides, ...

This page was created in 41.9 ms