Geocart Projections

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Eckert I

Classifications

Geocart menu class: Pseudocylindric
Geocart family: Eckert
Pseudocylindric
Equally spaced parallels
Neither conformal nor equal area

Graticule

Meridians: Equally spaced converging straight lines broken at the Equator. Central meridian is half as long as the Equator.
Parallels: Equally spaced straight parallel lines, 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 47°10' N. and S. Constant along any given latitude; same for the latitude of opposite sign. Constant along any given meridian.

Distortion

No point free of distortion. 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 graticule

Origin

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

Similar projections

Eckert III has meridians positioned identically, but parallels are 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.