http://www.geometrie.tuwien.ac.at/karto/ On a curved surface, measuring terrain properties is difficult, and it is not possible to see large portions of the Earth at once. In reality, a map can only be distortion-free if the actual shape it represents is also flat. Coronet, to stop Team Galactic's plot to control Dialga and Palkia. This thematic map type is appropriate for this presentation because it does not systematically distort area. This decision normally involves allowing for some type of distortion to occur in order to minimize or eliminate distortion for one or more other properties that are essential to the map's objective. The Mercator projection, for example, distorts Greenland because of its high latitude, in the sense that its shape and size are not the same as those on a globe. In conical or conic projections, the reference spherical surface is projected onto a cone placed over the globe. Similarly, when trying to project a spherical surface of the Earth onto a map plane, the curved surface will get deformed, causing distortions in shape (angle), area, direction or distance of features. On a tangent surface to the reference globe, there is no scale distortion at the point (or along the line) of tangency and therefore scale factor is 1. Some classic azimuthal projections are perspective projections and can be produced geometrically. http://slvg.soe.ucsc.edu/map.html The cartogram is now the final type of thematic map you will need to know for the exam and when it comes to these maps, remember they tend to focus more on expressing the data than the geography. These projections can also be equal area, conformal or equidistant. Distance and shape distortion increase sharply by moving away from the center of the projection. The map resorts to mathematics to curtail three major types of distortion – area, direction, and distance (and hence the German term for ‘triple’, Tripel, is in the name). In the tangent case, the cylinder’s circumference touches the reference globe’s surface along a great circle (any circle having the same diameter as the sphere and thus dividing it into two equal halves). On a secant surface to the reference globe, there is no distortion along the standard lines (lines of intersection) where SF = 1. Equidistant projections are neither conformal nor equal-area, but rather a compromise between them. The projections stretch from east to west according to their geometric constructions and are the same at any chosen latitude. http://demonstrations.wolfram.com/WorldMapProjections/ In the secant case, the cylinder intersects the globe; that is the diameter of the cylinder is smaller than the globe’s. The map projections with the least distortion will have the smallest gaps when folded into a sphere, while map projections with a lot of di. In planar (also known as azimuthal or zenithal) projections, the reference spherical surface is projected onto a plane. Properties Conformal Preserves angles locally, implying that local shapes are not distorted and that local scale is … A feature that has made Mercator projection especially suited for nautical maps and navigation is the representation of rhumb line or loxodrome (line that crosses meridians at the same angle) as a straight line on the map. Some images used in this set are licensed under the Creative Commons through Flickr.com.Click to see the original works with their full license. http://www.flexprojector.com/ © Eric Gaba – Wikimedia Commons user: Sting. 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