Geocart Projections

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Eckert II

Classifications

Geocart menu class: Pseudocylindric
Geocart family: Eckert
Pseudocylindric
Equal area

Graticule

Meridians: Equally spaced straight lines broken at the Equator. Central meridian is half as long as the Equator.
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

Scale

True along latitudes 55°10' N. and S. Constant along any given latitude; same for the latitude of opposite sign

Distortion

Free of distortion only at latitudes 55°10' N. and S. at the central meridian. Break at the Equator introduces excessive distortion there. Discontinuous ellipses are shown there owing to the plotting algorithm; actually, the shape is indeterminate on the Equator.

Usage

Novelty showing straight-line equal-area graticule

Origin

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

Similar projections

Eckert I has meridians positioned identically, but parallels are equidistant. Collignon projection has straight meridians and is equal area, but meridians are not broken at the Equator, and the poles are different.

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.