Mr. Snyder, chairman of the American Cartographic Association’s Committee on Map Projections, is also a research scientist with the U.S. Geological Survey.
This article appeared in the Christian Century February 24, 1988. Copyright by the Christian Century Foundation and used by permission. Current articles and subscription information can be found at www.christiancentury.org. This material was prepared for Religion Online by Ted & Winnie Brock.
SUMMARY
The projection of the Peter’s map shows all parts of the world in proportion to their true areas, while the Mercator Projection greatly distorts relative areas so that Europe, the Soviet Union, Canada and Greenland are shown as far larger relative to South America and Africa than they really are. Much controversy has surfaced over Peter’s map.
From its initial announcement, the Peters Projection has been surrounded by controversy: in over 40 articles on the subject, cartographers have vigorously denounced a number of Peters’s claims for the map, while he and his supporters have argued that his is the only world map that meets the concerns of people interested in social issues. UNESCO (the United Nations Educational, Scientific and Cultural Organization) , the National Council of Churches, and Lutheran and Methodist groups are among the organizations supporting Peters’s map.
Peters’s principal claim is that his projection shows all parts of the world in proportion to their true areas, while the Mercator Projection greatly distorts relative areas so that Europe, the Soviet Union, Canada and Greenland are shown as far larger relative to South America and Africa than they really are. The latter regions include important parts of the Third World that are populated primarily by dark-skinned peoples, and the former regions are populated mostly by light-skinned, industrialized peoples. Peters concluded that the Mercator Projection draws its popularity in large part from exaggerating the sizes of white-dominated regions and thus reflects a racist attitude -- a serious charge, if actually true.
There is no question about it: small Europe does show up more prominently on the Mercator Projection than it does on others that maintain correct area relationships (and there are scores of these besides Peters’s). If this unfortunate bias deserves to be corrected, why do cartographers object so strenuously to the claims Peters makes for his projection?
Their objections fall into two general categories: first, the simplistic proposal that the Peters Projection should be used exclusively (except possibly for navigation) , and second, the number of incorrect statements made about the projection, and therefore (by implication) about other projections.
Promoting the projection as a cure-all for mapping woes is indeed highly simplistic. No one flat projection, especially for world maps, can be ideal. Whereas a globe may be the most accurate world map, it is awkward to handle and to measure on, and of course we can look at only part of it at a time. And besides the many world map projections that show all areas in true proportion, some others are better for measuring certain distances, some for showing routes, some for showing shapes of landmasses and some for shapes of oceans. Other projections are better for mapping small regions such as continents and countries. The promotion of the Peters Projection thus seems to have taken on some of the same single-mindedness as claims for an "only true faith" or a panacea patent medicine. In the process of trying to raise social consciousness with his map, Peters has cast aside objectivity and important facts. And the financial aspect cannot be ignored: According to a 1987 handbook, A New View of the World: A Handbook to the World Map: Peters Projection, written by Ward L. Kaiser (the leading American proponent of the Peters Projection) and published by the Friendship Press of the National Council of Churches, the "Peters Projection map has reached a worldwide distribution of more than 16 million copies in six languages." The promotion of Peters’s projection clearly takes advantage of general unawareness that many other projections do show all countries in true proportion to their areas.
This article. "Peters Projection -- To Each Country Its Due on the World Map," (clearly credited to the Bulletin, the West German government publication in which it originally appeared in 1977) , was reprinted later that year by the American Congress on Surveying and Mapping (ACSM) , a professional association with some 11,000 members, in the November issue of its publication, also (incidentally) called the Bulletin. A decade later, the Friendship Press handbook quoted from the ACSM article and twice treated it as the ACSM’s endorsement of the Peters Projection. The ACSM’s 16-member board was so incensed by this false inference that it unanimously passed a resolution asking that this misuse of its name be retracted, since the ACSM has taken no official position on the projection.
The same 1977 article and several others say that Peters "created" this ‘new" map projection. Actually, Peters’s 1973 projection is the same as one rendered in 1855 by James Gall of Scotland, who published his developments of the Gall Orthographic Projection, as he wished it to be called, in an 1885 article titled "Use of Cylindrical Projections for Geographical, Astronomical and Scientific Purposes" (Scottish Geographical Magazine, Vol. 1, No. 4) , which is available in many American and European technical libraries. (Gall actually preferred one of his two other proposed projection systems.) The existence of this earlier work has led one committee of American cartographers to refer to the Peters Projection as the "Gall-Peters Projection." Gall in turn was just making a relatively simple modification of the Lambert Cylindrical Equal-Area Projection, published by Johann Lambert of Alsace in 1772 and well known to modern cartographers. Other equal-area projections include the oval-shaped Hammer Equal-Area Projection (1892) and an Eckert Equal-Area Projection (1906)
Sixteenth-century Flemish mapmaker Gerardus Mercator himself often used equal-area projections when he made maps for geographical purposes. He designed the Mercator Projection in 1569 strictly to help navigators; his is the only projection that shows rhumbs as straight lines: a navigator could connect two ports with a straight line on Mercator’s map and then proceed along a constant course based on the direction of this line. The Mercator Projection became so well known that people began to misuse it for geographical purposes -- against Mercator’s intent.
It is ironic that while the socially conscious recommend the Gall-Peters Projection for portraying the Third World with proper area scale, that map in fact represents the industrialized nations halfway between the equator and the North Pole with very little distortion of shape, while vertically elongating the Third World countries near the equator by a ratio of two to one. This has led Arthur H. Robinson, professor emeritus of cartography at the University of Wisconsin and author of the most widely used textbook on cartography, Elements of Cartography (John Wiley, 1984) , to describe the Gall-Peters land-masses as "somewhat reminiscent of wet, ragged, long winter-underwear hung out to dry on the Arctic Circle" ("Arno Peters and His New Cartography," The American Cartographer, October 1985)
On the February 3, 1984, broadcast of National Public Radio’s "All Things Considered," interviewer David Malpus challenged Kaiser, noting that the Peters Projection does not show Africa in its normal shape. Kaiser replied, "Well, one needs to ask what is the normal shape of Africa? Without having seen Africa from outer space, I’m really not in a very good position, nor perhaps [is] any of us, to say how it actually looks." But because we have navigators’ and surveyors’ mapping work applied to our globes, as well as the new evidence of photographs by astronauts, we know very well how Africa looks from space! Any flat projection will distort shapes, but Malpus’s point was that Peters’s distortion of Africa seemed excessive.
Actually, Lambert’s 1772 equal-area projection might serve better for Peters’s purpose, since it eliminates shape distortion at the equator, and applies it instead to other regions of the map, including the industrialized areas. There are other, more technical, problems with the claims for the Peters Projection; for example, he makes the computations for the projection seem very complicated while they are actually relatively simple.
Nevertheless, Peters and Kaiser appear to have successfully accomplished a feat that most cartographers only dream of achieving. Professional mapmakers have been wringing their hands for decades about the misuse of the Mercator Projection, but, as Peters stresses, the Mercator is still widely misused by school teachers, television news broadcasters and others. At least Peters’s supporters are rightly communicating the fact that the Mercator should not be used for geographical purposes, and numerous cartographers agree. The Gall-Peters Projection does show many people that there is another way of depicting the world.
If professional cartographers believe that the Gall-Peters is not a good alternative, at least it is challenging them to offer better ones. If they do not take advantage of the platform provided by this controversy, then they are assenting to the Gall-Peters in much the same way that the nonvoter assents to those holding political office.
The ACSM in 1985, through its member organization the American Cartographers Association, formed a Committee on Map Projections, which has prepared two booklets discussing in lay terms what should be involved in choosing a world map projection, and presents ten alternative projections, including the Mercator and the Gall-Peters. Choosing from several is not as easy as simply using one repeatedly, but the process is much more informative. A simplistic approach to the problems of map projection can result in misleading solutions.