Squaring the Sphere

This post was a comment on a shite Stalinst apologist site regarding the virtues of the Peters Map over the older Mercator Projection. The comment, shown below:

“Peter’s World Map is only one that represents countries, continents, and seas accurately according to their surface areas…..We have been duped into believing false facts about the Earth and for self serving political reason. Traditional Mercator maps show countries incorrectly in proportion or relative size to one another, to the advantage of the European colonial powers who drew the maps as they dominated and exploited the world, while the southern continents (Africa, South America, Australia) are shown far too small. “

I am neither a cartographer nor geographer but I have always loved maps. The comment struck reminded me of arguments years back over this issue, one where Mercator was portrayed as a cartographical demon and Peters as an angel.

The Demon

Mercator Projection

The Mercator projection was devised by Flemish mathematician Gerhard Kremer (= merchant in English or Mercator in Latin) in 1569 as a tool for navigation. Its layout is such that a navigator can simply draw a line between two points and he will know the correct compass bearing.

As a navigational aid the Mercator projection is excellent but it was never intended for use in world maps as it increasingly inflates the size of land masses, the further they are away from the equator: as a result Greenland appears to be as big as Africa. Sadly that did not stop its use by non geographers in wall maps, atlases and just about anywhere else. This would appear to give some credence to the argument that its flaws - making Western Europe appear much larger than it is reality - suited the colonial powers and thus ensured its longevity. In reality the most likely reason for its continued use outside the world of navigation is inertia rather than racism.

Geographers have criticised the use of the Mercator Projection for over 100 years. For example, in 1902, a cartographer warned, "People's ideas of geography are not founded on actual facts but on Mercator's map." In 1953 Arthur Robinson in the fist edition of Elements of Cartography textbook, called the Mercator projection "of little use for purposes other than navigation.”

The Angel

Peters Projection

In 1973 historian and journalist Arno Peters announced a new map projection that that treated countries fairly by representing area accurately. Peters claimed that his projection more fairly displayed third world countries than the Mercator projection because of its distortion of Eurasia and North America. When announced it was also claimed in some quarters that the Peters Projection was the only "area-correct" map, it had no “extreme distortions of form" and was "totally distance-factual.

Gall Orthographic Projection

While the Peters map does more or less show the attribute the correct area to land masses, to say that it is the only “area correct” map is simply not true. Equal area maps have been around for centuries. The Peters Projection itself is identical to one described in 1855 by Scotsman James Gall. In turn the Gall Orthographic Projection was a modification of the Lambert Cylindrical Equal-Area Projection, published in 1772. It would appear that Peters arrived at his projection independently and there is no suggestion of plagiarism on his behalf.

Lambert Cylindrical Equal Area Projection

Many of the other claims are also false. The Peters projection still has extreme distortion in the polar regions and significant distortion along the equator. Surprisingly the minimum distortion actually occurs at 45 degrees of latitude (where Germany sits). This in itself partly undermines any assertion that it treats the Third World more justly, for it significantly changes the shape of both Africa and South America.. Where it does work, is to challenge our perceptions of the planet


Squaring the sphere

Presenting Cartography as a straight fight between Mercator and Peters ignores the hundred of projections developed over the centuries. However, because any projection tries to render a globe onto a cylinder there is not a world map in existence that does not distort distance, shape, area, or direction in some way shape or form. Neither the Peters nor the Mercator projection gives a good indication of what the earth really looks like.

Winkel Tripel Projection

Other projections do give a rather better representation of the Earth than either Mercator or Peters. For example The National Geographic Society uses the Winkel Tripel projection, It is still flawed in many ways but it does presents the world in a more globe-like manner. At the end of the day, however, if you want to see the world as it really is, get a globe

Further Reading

Peters v Mercator

Diversophy An explanation and Guide to the Peters Map

Social Consciousness and World Maps by John P Snyder

Winkel Triple Projection

Wikipedia article on Gall-Peters Projection

Wikipedia article on the Mercator Projection


Mercator
Peters
Maps