Search results
Results from the WOW.Com Content Network
Topographic maps are also commonly called contour maps or topo maps. In the United States, where the primary national series is organized by a strict 7.5-minute grid, they are often called or quads or quadrangles. Topographic maps conventionally show topography, or land contours, by means of contour lines.
The National Map is part of the USGS National Geospatial Program. [3] The geographic information available includes orthoimagery (aerial photographs), elevation, geographic names, hydrography, boundaries, transportation, structures and land cover. The National Map is accessible via the Web, as products and services, and as downloadable data ...
The United States Geological Survey (USGS) topographical survey maps included contour representation of relief, and so maps that show relief, especially with exact representation of elevation, came to be called topographic maps (or "topo" maps) in the United States, and the usage has spread internationally.
Enlargeable map of the 50 U.S. states by mean elevation. This list includes the topographic elevations of each of the 50 U.S. states, the District of Columbia, and the U.S. territories. [1] The elevation of a geographic area may be stated in several ways. These include: The maximum elevation of the area (high point); [a]
Since topographic maps typically show elevation using contour lines, the exact elevation is typically bounded by an upper and lower contour, and not specified exactly. Prominence calculations may use the high contour (giving in a pessimistic estimate [ 10 ] [ 11 ] ), the low contour (giving an optimistic estimate), their mean (giving a ...
In cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. [3] A contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes. [4] The contour interval of ...
Map of countries coloured according to their highest point. The following sortable table lists land surface elevation extremes by country or dependent territory. Topographic elevation is the vertical distance above the reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface.
A map of Europe using elevation modeling. In its contemporary definition, topographic mapping shows relief. In the United States, USGS topographic maps show relief using contour lines. The USGS calls maps based on topographic surveys, but without contours, "planimetric maps."