Directory of Map Projections

What is a projection?

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equidistant cylindric

equirectangular

rectangular

Marinus

la carte parallélogrammatique

Parameters: Standard parallel

Classifications

cylindric
equidistant

Graticule

Meridians: Equally spaced straight parallel lines more than half as long as the equator.
Parallels: Equally spaced straight parallel lines, perpendicular to and having wider spacing than meridians.
Poles: Straight lines equal in length to the equator.
Symmetry: About any meridian or the equator.

Scale

True along two standard parallels equidistant from the equator and along all meridians.
Too small along the equator but increases with distance from the equator along the parallels.
Constant along any given parallel; same scale at the parallel of opposite sign.

Distortion

Infinitesimally small circles on the globe (indicatrices) are circles on the map at latitudes 30°N and S. For this choice of standard parallels. Elsewhere, area and local shape are distorted.

Other features

Simple modification of Plate Carree having east-west compression.
Conceptually projected onto a cylinder secant to the globe along the chosen standard parallels.
Not perspective.

Usage

Simple outline maps of regions or of the world or for index maps Used only in the spherical form.

Origin

Marinus of Tyre about A.D. 100.

Description adapted from J.P. Snyder and P.M. Voxland, An Album of Map Projections, U.S. Geological Survey Professional Paper 1453. United States Government Printing Office: 1989.