Peters Projection

No map of the world is perfect, since the surface of a sphere cannot be projected onto a flat surface without some degree of distortion. For hundreds of years, the most popular projection of the planet's surface onto a flat map was the Mercator projection, even though it seriously distorted the relative sizes of many countries. For example, Mercator maps show Greenland to be roughly the same size as Africa, when, in reality, Africa is actually fourteen times larger. Africa also looks considerably smaller than Russia on a Mercator map, even though Africa is actually 33% larger. However, generations of navigators weren't bothered much by Mercator's misrepresentations, since they cared most about longitude and latitude, which the Mercator projection handles rather well.

In 1974, a historian and cartographer named Dr. Arno Peters introduced a map which projected the world onto an equal and consistent grid, which made it possible to accurately compare the sizes of countries and visualize the true distance between any two points on the earth. For those who grew up with the Mercator map, the Peters projection map appears to be stretched vertically, and Africa suddenly looks huge.

A variety of social and religious groups fervently argue that since the Mercator map makes many countries appear smaller than they really are, people (especially children) reading them may infer that certain countries are innately more important than others. This rhetoric has often escalated to the point where the Mercator map is openly described as being "racist". Many of these groups are working to address this perceived problem by lobbying schools around the world to adopt the Peters projection map in classrooms. This seemingly noble movement is not without controversy, however, since educators, well-aware of the Mercator map's deficiencies, were already adopting maps based on other projections, some of which are even more accurate than Peters's. Others argue that Arno Peters wasn't even the first person to devise such a projection, since James Gall had come up with the same idea in 1855 (which is why some refer to it as the Gall-Peters projection).

The movement to promote the Peters projection map got a big boost when it was featured on an episode of the second season of NBC's Emmy-winning show, The West Wing, entitled "Somebody's Going to Emergency, Somebody's Going to Jail", which aired on February 28th, 2001.

Another sad example of self-promotion disguised as social theory.

In a 1973 speech to the United Nations, historian Arno Peters declared that the Mercator projection was "racist", and promoted a map projection that didn't distort areas.  Coincidentally, it was called the "Peters Projection". More about this below.

(What's this? Any ship's captain who wants a map showing his course as a straight line is a racist?)

He convinced several United Nations agencies (e.g. UNICEF) and the World Council of Churches to adopt his projection for all uses. I first learned about the Peters Projection from Irving Wallace's fascinating work The People's Almanac.

What's more, in 1983, Mr. Peters somehow convinced the World Council of Churches' publication arm Friendship Press to publish his book The New Cartography: A New View of the World.   This book revealed the unsoundness of his reasoning.

Peters took some valid basic points:

• The Mercator projection distorts areas.
• Maps using the Mercator projection are often used in schools to teach world geography.
• Perhaps this is an attempt to inculcate notions of racial superiority in young minds.

and added a whole lot of anti-intellectual baggage on top of it:

• He realized that most people had better things to do with their time than learn enough mathematics to understand map projections.   He turned this into a statement that cartographers try to confuse the masses with mathematics.
• He invented several properties that a "perfect" map should have.  One of these was a rectangular grid; any map that had a curved grid was an attempt to "trick" people into believing the earth was flat. (Hello? Any line you draw on a globe will be curved!) Somehow, only the Peters projection had all these properties.
• Although a conformal projection (such as the Mercator projection) doesn't distort angles, it does distort distances in a continuous fashion. As a result, shapes covering a large part of the Earth aren't represented correctly.  Because of this, he dismissed the Mercator projection as "useless".
• In general, he threw away the notion of selecting a map projection to suit a map's purpose, stating that the Peters projection should be used for all purposes. (We'd never have discovered the ozone hole that way).

If Peters had said "The Mercator projection isn't being used for the purpose it was designed for, use a better projection", he would be accepted.  Instead his message was, "Use my projection for all purposes. All other projections are evil.", revealing himself to be either a confidence trickster or a dangerous fool.

In 1985, Arthur H. Robinson, a professor at the University of Wisconsin, published a scathing denunciation¹ of The New Cartography.  In it, he revealed that Peters had received his Ph. D. in 1945 from the University of Berlin.  The topic of Peters' dissertation? Der Film als Mittel der öffentlicher Fürhung, that is, The use of film as a propaganda medium.

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So anyway, what's left of Peters' ideas?

• You should try not to distort the sizes of countries when teaching schoolchildren about them.
• The Mercator projection distorts areas; don't use it in a classroom setting.

These points are correct.  However, cartographers have known this and have been telling people this for years.

There are many, many types of equal-area map projections (follow the link for a list).  Most of them distort shapes far less than the Peters projection does.  Thus, Mr. Peters invented his spurious properties to weed out the competition.

Peters' projection is a special case of the Gall Cylindrical Equal-Area projection with its standard parallels set at 45 degrees.  It's nothing new; in fact, any example of the Cylindrical Equal Area projection has the "properties" Peters so highly touted.

On the Earth, Africa is extends almost the same distance north-to-south that it does east-to-west. On Peters' map, it is about twice as high as it is wide.  If you move the standard parallels closer to the Equator, say to 30 degrees, things begin to look much more realistic.  And areas still aren't distorted.

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¹Robinson, Arthur H. "Arno Peters and his New Cartography."
American Cartographer 12 (2 1985): 103-11.

Other sources:
http://www.nypl.org/research/sc/sources/aboutmap.html
http://www.ncccusa.org/friend/maps.html#anew
http://www.csulb.edu/~rodrigue/geog140/lectures/projections.html