Winkel Tripel

The Winkel Tripel projection is a modified azimuthal map projection created by Oswald Winkel in 1921. It is currently widely used for world maps, replacing the Robinson projection as the preferred projection used by world map publishers such as the National Geographic Society. The Winkel Tripel projection is calculated based on a spheroid, rather than an ellipsoid.

The projection is neither conformal nor equal-area. Scales are constant only along the Equator and true along the central meridian. Parallels are curved except at for the equator and the poles. The distortion of area and size is moderate, but increases toward the poles.

More Information

 * Winkel.org - Winkel Tripel Projections
 * Winkel's Tripel Projection
 * Modified Azimuthal Projections
 * The Nomenclature and Classification of Map Projections Empire Survey Review No. 51, Vol VII January 1944 Pages 190-200 ; L.P. Lee, Lands Survey Department, Wellington, N.Z.
 * Matching the Map Projection to the Need
 * List of ESRI-supported map projections
 * Weisstein, Eric W. Map Projections. From MathWorld--A Wolfram Web Resource.
 * Map Projections''. Atlas of Canada.
 * Cartographical Map Projections'', Carlos A. Furuti website, www.progonos.com.
 * Elements of Map Projection. (26 MB download) U.S. Coast and Geodetic Survey, Special Publication 68 (1938).
 * Map Projections. USGS Publications. December 2000.
 * What are map projections? ArcGIS 10 Online Help
 * University of Colorado at Boulder - Map Projection Overview with Illustrations
 * Data Projections. GeoCommunity Web site.
 * Wiki.GIS.com - Types of Projections