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Pseudocylindrical Projections

Mollweide Projection
The Mollweide is another conventional equivalent projection. On this projection, the entire Earth is represented within an ellipse. Parallels of latitude are straight lines parallel to the Equator. The spacing of parallels along the central meridian is calculated to ensure that all areas on the map are equal to the corresponding areas on the globe. Like the Sinusoidal projection, distortion is minimal near the intersection of the Equator and the central meridian and increases toward the edges of the map.
Eckert IV projection
The Eckert IV projection, used for world maps, is a pseudocylindrical and equal-area. The central meridian is straight, the 180th meridians are semi-circles, other meridians are elliptical. Scale is true along the parallel at 40:30 North and South.
Eckert VI projection
The Eckert VI projection , used for maps of the world, is pseudocylindrical and equal area. The central meridian and all parallels are at right angles, all other meridians are sinusoidal curves. Shape distortion increases at the poles. Scale is correct at standard parallels of 49:16 North and South.
Robinson Projection
The Robinson projection is based on tables of coordinates, not mathematical formulas. The projection distorts shape, area, scale, and distance in an attempt to balance the errors of projection properties.
Wagner IV
A pseudocylindrical, equal-area projection invented by Putnins and called the Putnins P2' but almost universally known today in GIS circles as the "Wagner IV". Scale True along latitudes 4259’ North and South. Constant along any given latitude and the same for the latitude of opposite sign. Distortion 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 4259’ North and South at the central meridian. Usage Thematic world maps. Origin Presented in 1934 by Reinholds V. Putnins of Latvia. An identical projection, the Wagner IV projection, was presented by Karlheinz Wagner of Germany in 1949.
Wagner VII
A modified azimuthal, equal-area projection invented by Putnins and called the Putnins P2' but almost universally known today in commercial GIS software as the "Wagner IV". Scale Decreases along the central meridian and the Equator with distance from the center of the projection. Distortion Considerable shape distortion in polar areas. Usage Thematic world maps, such as climatic maps prepared by the U.S. Department of Commerce. Origin Presented by Karlheinz Wagner of Germany in 1941, the Wagner VII is a modification of the Hammer projection and is also known as the Hammer-Wagner projection.
Sinusoidal Projection
Sinusoidal equal-area maps have straight parallels at right angles to a central meridian. Other meridians are sinusoidal curves. Scale is true only on the central meridian and the parallels. Often used in countries with a larger north-south than east-west extent.
Homolosine Projection
The homolonsine projection is a hybrid projection formed by using a Sinusoidal projection between 40o 44' N and 40o 44' S. A Mollweide projection is used for areas outside this range. The resulting projection is an equivalent projection, but avoids the pointed look of the Sinusoidal projection.
Van der Grinten
A curved modification of the Mercator projection that is neither equal-area nor conformal. Although it is usually classed with the various pseudocylindrical projections it is not really a pseudocylindrical projection. Scale Only the Equator is true to scale. Distortion The central meridian and Equator are straight lines. All other meridians and parallels are arcs of circles. Great distortion in polar regions. Most maps using this projection do not extend past Greenland and the outer rim of Antarctica. Usage used for world maps. Used by the National Geographic Society for their standard world map until 1988, which resulted in adoption of this projection by many other groups. origin Presented in 1904 by Alphons J. van der Grinten of Chicago writing in a German geographical journal and patented in the United States in 1904. One of four projections published in 1904, the "Van der Grinten" projection used within Manifold is the first one of the series and was invented in 1898. It is the best known and the one commonly used. Van der Grinten published the projection using a geometric construction. Manifold uses the 1979 formulae published by Snyder. Limiting Forms Used only in the spherical form.
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