Geocart Projections

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Boggs eumorphic


Equal area


Meridians: Central meridian is a straight line half as long as the Equator. Other meridians are equally spaced complex curves intersecting at the poles and concave toward the central meridian.
Parallels: Unequally spaced straight parallel lines perpendicular to the central meridian
Poles: Points
Symmetry: About the central meridian or the Equator


True along latitudes 40°15' N. and S. Constant along any given latitude; same for the latitude of opposite sign


Distortion is severe near outer meridians at high latitudes but can be substantially reduced by interruption. Free of distortion only at latitudes 40°15' N. and S. at the central meridian.

Other features

Designed as the arithmetic mean of the Sinusoidal and Mollweide projections for north-south (y) coordinates only, when drawn with the same area scale


Thematic world maps in atlases and textbooks, usually in interrupted form


Presented by S. Whittemore Boggs (1884-1954) of the U.S. Department of State in 1929

Similar projections

Several pseudocylindricals, such as the Sinusoidal and Craster Parabolic.

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.