Geocart menu class: Pseudocylindric
Geocart family: Wagner
Meridians: Central meridian is a straight line half as long as the Equator. Other meridians are equally spaced portions of ellipses (less than semiellipses) that would intersect beyond the poles and are concave toward the central meridian. The meridians at 103°55' east and west of the central meridian are circular arcs.
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 42°59' N. and S. Constant along any given latitude; same for the latitude of opposite sign
Distortion is not as extreme near outer meridians at high latitudes as it is on pointed polar pseudocylindrical projections, but there is considerable distortion throughout polar regions. Free of distortion only at latitudes 42°59' N. and S. at the central meridian.
Presented by Reinholds V. Putnins of Latvia in 1934
Wagner IV projection (1949) is identical.
Werenskiold III projection (1944) is identical, except that true scale is maintained along the Equator by enlarging the map.
Putnins P2 equal-area projection (1934) uses the same portions of ellipses, but the poles are points.
Putnins P1 and P1' projections (1934) have meridians identical in shape and position to those of Putnins P2 and P2', respectively, but parallels are equally spaced, and the projections are not equal area.
Robinson projection is not equal area, meridians are not elliptical, and parallels are spaced differently.
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.