Terrain or relief is an essential aspect of physical geography, and as such its portrayal presents a central problem in cartography, and more recently GIS and 3D Visualization. True-color image of the Earths surface and atmosphere Physical geography (also know as geosystems or physiography) is a subfield of geography that focuses on the systematic study of patterns and processes within the hydrosphere, biosphere, atmosphere, and lithosphere. ... Cartography or mapmaking (in Greek chartis = map and graphein = write) is the study, practice, science and art of making maps or globes. ... A geographic information system (GIS) is a system for managing data that has a spatial specialized form of an information system. ... Visualization of how a car deforms in an asymmetrical crash using finite element analysis. ...

The most obvious way to depict relief is through physically molding the map, thus molded or carved solid terrain models and molded-plastic raised-relief maps.

On flat paper maps, terrain can be depicted in a variety of ways, outlined below:

Contour lines or Isohypses are isolines showing equal elevation. This is the most common way of numerically showing elevation, and is familiar from topographic maps. Most 18th and early 19th century national surveys did not record relief across the entire area of coverage, calculating only spot elevations at survey points. 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. Elevation contour map A contour line (also level set, isopleth, isogram or isarithm) for a function of two variables is a curve connecting points where the function has a same particular value. ... An isohypse is a line of equal or constant elevation on a graph, plot, or map; an isopleth of elevation. ... Isolines are lines on a map describing the intersection of a real or hypothetical surface with one or more horizontal planes. ... Example of a topographic map with contour lines Topographic maps, also called contour maps, topo maps or topo quads (for quadrangles), are maps that show topography, or land contours, by means of contour lines. ... (17th century - 18th century - 19th century - more centuries) As a means of recording the passage of time, the 18th century refers to the century that lasted from 1701 through 1800. ... Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... The United States Geological Survey (USGS) is a scientific agency of the United States government. ... Example of a topographic map with contour lines Part of the same map in a perspective shaded relief view illustrates how the contour lines of the original follow the terrain Topographic maps, also called contour maps, topo maps or topo quads (for quadrangles), are maps that show topography, or land...

Example of a topographic map with contour lines

Hypsometric tints are a variant on contour lines. They depict ranges of elevation as bands of graduated color. The most common color scale runs from greens in the lowlands through yellows ans browns to greys and whites on alpine peaks. Description: Example of a topographic map with contour intervals Source: Sample taken from the public domain USGS Digital Raster Graphic file o44072d6. ... Description: Example of a topographic map with contour intervals Source: Sample taken from the public domain USGS Digital Raster Graphic file o44072d6. ...

Hachures are an older mode of representing relief. They show orientation of slope, and by there density they provide a general sense of steepness. Being non-numeric, they are less useful to a scientific survey than contours, but can successfully communicate quite specific shapes of terrain. Look up Slope in Wiktionary, the free dictionary. ...

Shaded relief or hill-shading simulates the cast shadow thrown upon a raised relief map, or more abstractly the shadow of the sun. The conventional angle of the light source for such models (upper left) makes such depictions in the northern latitudes non-represeetnative of actual light/shadow patterns. Traditionally drawn with charcoal and other traditional media, Shaded relief is today almost exclusively computer-generated, with a resulting different look and feel. Much work has been done in digitally recreating the work of Swiss master Eduard Imhof, widely regarded as the master of manual hill-shading technique and theory. Eduard Imhof Signature Eduard Imhof (1895-1986) was a professor of cartography at the Swiss Federal Institute of Technology, Zurich, from 1925 - 1965. ...

Portrayal of relief is especially important in mountainous regions. The Commission on Mountain Cartography of the International Cartographic Association is the best-known forum for discussion of theory and techniques for mapping these regions. A mountain is a landform that extends above the surrounding terrain in a limited area. ...