Directory of Map Projections

What is a projection?

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conformal world in an ellipse

Parameters: Modular angle 0° << ß << 90°

Classifications

conformal

Graticule

Meridians: Central meridian is straight. Other meridians are complex curves.
Parallels: Equator is straight. Other parallels are complex curves.
Poles: Points.
Symmetry: About the central meridian and the equator.

Limiting forms

As the modular angle that controls the shape of the ellipse approaches 90°, the map increasingly resembles the Lagrange circular projection.

Scale

Increases rapidly with distance from the center.

Distortion

Great distortion of area near the poles and the 180th meridians. Conformality fails at the poles.

Other features

The shape of the bounding ellipse can be varied. Lee uses an axial ratio of about 1.97 to 1 for convenience in using tabular values.

Usage

Novel whole-world maps.

Similar projections

See note under Adams projection of the world in a square I.

Origin

Presented by Oscar Sherman Adams (1874–1962) of the U.S. Coast and Geodetic Survey in 1925. Corrected by Andre Gougenheim in 1950 and Laurence Patrick Lee (1913-1985) of New Zealand in 1965.

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.