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View all inventor worksheets. View all athlete worksheets. View all civil rights worksheets. View all natural wonders worksheets. View all landmark worksheets. Using a cylinder and a globe with light is a simplified explanation as to how the Mercator projection works. In reality it is very complicated to derive the projection and it takes complex mathematical formulas to fully explain it Israel, In , Edward Wright, an English mathematician, first explained the very complicated mathematics of the Mercator projection and throughout the s several other mathematicians attempted to find easier explanations.
Today, most basic explanations as to how the Mercator projection work use the cylinder and a globe with light description. This distortion stretches landmasses like Greenland and Europe and they appear much bigger than places that are close to the equator such as South America and Africa. Despite these errors the popularity of the projection as a navigation aid and its easily readable rectangular grid meant that it was easy to reproduce in printed materials like atlases and wall maps.
As a result, it became a standard map for classrooms. Throughout the s geographers and scholars have claimed that the Mercator projection is incorrect and that it should only be used for navigation.
It was not until the s though that the projection began to receive wide criticism. In for instance, seven professional geographic organizations in North America adopted a ban on this and other rectangular coordinate maps Rosenberg. Greenland, for instance is not bigger than South America, but it appears to be on Mercator maps. Other critics say that this projection and the large size of continents like Europe gave an advantage to the colonial powers because it made them appear larger than they really are.
Mercator variant A differs from variant B only in projection parameters. They share the same algorithm. Mercator variant C differs from variant B only in projection parameters.
The poles cannot be represented on the Mercator projection. Large area distortion makes the Mercator projection unsuitable for general geographic world maps and thematic mapping. It is the de facto standard for web maps and online services. With this coordinate system, the geodetic coordinates defined on the WGS 84 datum are projected as if they were defined on a sphere, using a sphere-based version of the Mercator projection. The sphere's radius is equal to the WGS semimajor axis, Combining geodetic coordinates on the ellipsoid with spherical equations consequently leads to a coordinate system that does not preserve the scale factor in all directions.
Therefore, the Web Mercator coordinate system is not conformal, and besides enormous area and distance distortions away from the equator, it also does not project rhumb lines as straight lines. Two methods exist for emulating the Mercator projection used by the web services.
If the Mercator implementation supports spheroids ellipsoids , the projected coordinate system must be based on a sphere-based geographic coordinate system.
This will force the use of sphere equations. The implementation of Mercator auxiliary sphere has sphere equations only. Among cartographers and geographers, the name Gerardus Mercator is not simply well-known, but is uttered with reverence.
As far as we know, he was the first person to apply the term atlas to a collection of maps in book form. The book was actually published after Gerardus's death by his son. It has also been said that Mercator saw a new form of lettering in Italy and introduced it to Northern Europe , naming it italics in honor of its place of origin. Although neither story can be substantiated absolutely, they help form the basis of a cartographic legend.
Gerardus Mercator. Mercator's main claim to fame can be ascribed to two cartographic applications. He was the first cartographer to use latitude and longitude as an aid on sailors' maps. By applying a grid of intersecting lines invented centuries earlier by the Greeks to navigational maps, he paved the way for modern nautical charts. His second contribution was a map that still bears his name—the Mercator projection, published in No wonder future cartographers and laymen simply called it the Mercator projection.
This map revolutionized navigation because any line drawn between two points on a map is a sailor's compass setting that only needs to be adjusted to compensate for magnetic north. Because most navigators in the sixteenth century relied on their own personal and very secret maps, acceptance of the map projection wasn't immediate. Drawing a line between two points on the map or chart shows a sailor the direction he needs to sail.
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