Decision Support System for Map Projections of Small Scale Data

Decision Support System for Map Projections of Small Scale Data

Mercator

Usage:*

The meridians of longitude of the Mercator projection are vertical parallel and equally spaced lines, cut at right angles by horizontal straight parallels which are increasingly spaced toward each pole so that conformality exists. The spacing of parallels at a given latitude on the sphere is proportional to the secant of the latitude.

It is used for navigation since it allows a sailing route between two points be represented as a straight line. The Mercator projection has been standard since 1910 for nautical charts prepared by the former U.S. Coast and Geodetic Survey.

Though it increasing distorts area as you get near the poles, the Mercator projection is fundamental in the development of map projections, especially those which are conformal. It remains a standard navigation tool. It is also especially suitable for conformal maps of equatorial regions.

* Usage information source:

Snyder, John P. Map Projections - A Working Manual Paper U.S. Geological Survey Professional Paper 1395. Washington: United States Government Printing Office, 1987.

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