The Gall-Peters projection is a variation of the generic Equal Area Cylindrical, in which the latitude of the standard parallel is always 45 degrees. It was originally presented by James Gall in 1855, and is also known as the Gall Orthographic projection.
The Equal-Area Cylindrical projection represents an orthographic projection of a sphere onto a cylinder. Like other regular cylindrical projections, the graticule of the normal Equal-Area Cylindrical projection consists of straight equally spaced vertical meridians perpendicular to straight unequally spaced horizontal parallels. To achieve equality of area, the parallels are spaced form the Equator in proportion to the sine of the latitude. This is the simplest equal-area projection. This projection is supported on spheres only.
The "GallPeters" Projection has the following Parameters:
|
Parameter Name |
Parameter String |
Units |
|
Longitude of the Central Meridian |
central_meridian |
|
|
False Easting |
false_easting |
|
|
False Northing |
false_northing |
NOTE: Only a spherical form of this projection is used. The semi-major axis of the ellipsoid (sphere) is used for forward and inverse projection from grid to geodetic coordinates within the system wherein this projection is incorporated.