Geocart Projections

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Craster parabolic

Putniṇš P4

Classifications

Geocart menu class: Pseudocylindric
Pseudocylindric
Equal area

Graticule

Meridians: Central meridian is a straight line half as long as the Equator. Other meridians are equally spaced parabolas intersecting at the poles and concave toward the central meridian.
Parallels: Unequally spaced straight parallel lines, farthest apart near the Equator; spacing changes very gradually. Perpendicular to the central meridian.
Poles: Points
Symmetry: About the central meridian or the Equator

Scale

True along latitudes 36°46' N. and S. Constant along any given latitude; same for the latitude of opposite sign

Distortion

Distortion is severe near outer meridians at high latitudes but somewhat less than that of the Sinusoidal projection. Can be substantially reduced by interruption. Free of distortion only at latitudes 36°46' N. and S. at the central meridian.

Usage

Thematic world maps in textbooks

Origin

Presented by John Evelyn Edmund Craster (1873-?) of England in 1929. Developed further by Charles H. Deetz and O.S. Adams in 1934

Aspects

Oblique aspect used for map of Asia by National Geographic Society

Other names

Putnins P4, independently presented in Latvia in 1934.

Similar projections

Several pseudocylindricals, such as the Sinusoidal and the Boggs Eumorphic
Putnins P3 projection (1934) has meridians, poles, and Equator identical to those of the Craster, but parallels are equally spaced.

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.