Geocart Projections

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Eckert IV


Equal area


Meridians: Central meridian is a straight line half as long as the Equator. Other meridians are equally spaced semiellipses, concave toward the central meridian. The outer meridians (180° east and west of the central meridian) are semicircles.
Parallels: Unequally spaced straight parallel lines, widest separation near the Equator. Perpendicular to the central meridian.
Poles: Lines half as long as the Equator
Symmetry: About the central meridian or the Equator


True along latitudes 40°30' N. and S. Constant along any given latitude; same for the latitude of opposite sign


Free of distortion only at latitudes 40°30' N. and S. at the central meridian.


Thematic and other world maps in numerous atlases and textbooks and for sheet maps


Presented by Max Eckert (1868-1938) of Germany in 1906


Like most projections, transverse and oblique aspects can be prepared, although they are seldom used in this case.

Similar projections

Eckert III has meridians positioned identically, but parallels are equally spaced. Putnins P2' has meridians that are only portions of semiellipses, but parallels are also spaced for equal area.

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.