The Peters Map Is Fighting the Last War

News of Boston public schools’ decision to go with the Peters projection has gone viral over the past week, and my teeth have not stopped itching. Largely because this is very much old news: Arno Peters began promoting “his” projection 44 years ago, and the Peters map has been making the rounds in certain circles ever since then. This is not new, and the media is showing its feckless streak in its lack of awareness of that fact. After all, the West Wing episode with the Peters map in it was broadcast 16 years ago.

The Gall-Peters projection is just one of several rectilinear equal-area projections; that Peters promoted it as a tool of social justice and anti-colonialism made it awfully appealing to people who are concerned with such issues. (They are not wrong to be concerned with such issues.) But cartographers have generally always been appalled by the projection, by Peters’s rhetoric and by his general ignorance of what had gone before. (Peters’s map had already been described by James Gall in 1885; the Mercator projection’s insufficiencies as a wall map had long been known; and there were many other projections, from the Van der Grinten to the Mollweide to the Goode homolosine, that were already being used in the Mercator’s stead.)

(The Mercator projection, for its part, makes a crap wall map: its virtue is that rhumb lines—compass headings—are straight lines, making the Mercator ideal for navigation. It’s worth emphasizing that Mercator himself died in 1594. Again, see Monmonier’s book on the subject.)

Cartographers’ response to the Peters projection is essentially, usually (and correctly) that every map projection is a compromise, because every map projection is an attempt to represent a round planet on a flat surface. All maps, in other words, lie; or at least no map is exempt from lying; or at least the Mercator is no more a liar than any other projection. It’s essentially an effort in debunking—the tedious repetition of “well, actually” to a credulous audience that doesn’t care enough to listen all the way through. (And besides: the company selling the Peters map thoroughly agrees with them!)

For the latest examples of this, see Caitlin Dempsey’s piece on teaching context, and Andy Woodruff’s response to the latest round of this. They’re good pieces, worth reading—but I can’t help wonder whether something different needs to be tried. But then again: what problem are we trying to solve? Media and public credulity? The fact that the Peters projection, bluntly, sucks? The campaign—and it is a campaign—behind it?

But the campaign for the Peters map is increasingly irrelevant. In late 2015 I argued that the debate over the right projection for wall maps was the cartographic equivalent of fighting the last war. The Peters map was a 20th-century response to a 19th-century problem (the Mercator on wall maps) that had already largely been solved earlier in the century. Sure, there are still wall maps out there that use the projection (I’m looking in your direction, IKEA), but by and large it’s not used nearly as much as the Peters defenders would have you think.

But 21st-century mapmaking is not about wall maps: it’s about web maps. As I said in 2015:

Every online map service uses a variant of the Mercator projection called Web Mercator. Whatever its shortcomings—and there are many, owing to the fact that its calculations use a spherical Mercator model to save computational cycles—Web Mercator has become the de facto standard. And the size distortions at small scales that have made the Mercator projection the target of so much ire over the decades are simply moot for most use cases.

In many ways the past debates over the Mercator are moot: arguing over the right projection for wall-sized world maps—Mercator vs. Peters vs. Robinson—is fighting the last war. Mercator has become the default option for online mapmaking, simply because so many data visualization maps rely on Google Maps or OpenStreetMap for their base map layer. Other projections will be reserved for the professionals, people with access to more sophisticated mapmaking tools and the skill to use them, but for the most part, when data is mapped on the Internet, it’ll be mapped according to Mercator.

Zoom out in Google Maps or OpenStreetMap, and what do you see? The Mercator projection, with Greenland in all its inappropriately giant glory. (Apple Maps turns into a globe when you zoom out far enough, but Apple Maps are app-only.) The reason why this isn’t generally seen as a problem is that hardly anyone uses Google Maps as a world map: like topographic maps that use UTM, at close range Mercator works just fine.

While there are efforts under way to use other projections in web maps, it’s unlikely that the Mercator-vs.-Peters battle—a false dichotomy if there ever was one—will migrate to the digital arena.

Previously: The Peters Projection Comes to Boston’s Public SchoolsIn Defence of the Mercator ProjectionHow the Mercator Projection Won the Internet.

Book Roundup for March 2017

Out this month: the English translation of Andrea Carandini’s massive two-volume, 1300-page Atlas of Ancient Rome (Princeton University Press), which “provides a comprehensive archaeological survey of the city of Rome from prehistory to the early medieval period.” See the book’s website. [Amazon]

Other books seeing publication this month: Picturing America: The Golden Age of Pictorial Maps by Stephen J. Hornsby (University of Chicago Press), a history of the pictorial map art form during the 20th century [Amazon]; and Zero Degrees: Geographies of the Prime Meridian by Charles W. J. Withers (Harvard University Press), a history of prime meridians and the standardization thereof [Amazon].

An update: Mapping the Holy Land (I. B. Tauris) which I originally understood to be coming out in January, is now slated for publication this week. [Amazon]

Related: Map Books of 2017.

Map Exhibitions Around the World

Mapping the Philippine Seas, an exhibition of 165 maps and sea charts of the Philippine archipelago from the 16th to the 19th century from the private collections of the Philippine Map Collectors Society. At the Metropolitan Museum of Manila. Opened 15 March, runs until 29 April. BusinessWorld. [WMS]

The Osher Map Library’s next exhibition, To Conquer or Submit? America Views the Great War, opens this Thursday (Facebook, Eventbrite). It “commemorates and explores American participation in the Great War—the ‘War to End All Wars’—with a sample of informative and propagandistic posters, maps, and atlases” from the Osher collections, which are based at the University of Southern Maine in Portland.

The World According to Blaeu: Joan Blaeu’s 1648 map of the world, more than two by three metres in size, will be on display at the National Maritime Museum in Amsterdam from 14 April to 31 December. [WMS]

The Peters Projection Comes to Boston’s Public Schools

Gall-Peters projection (Wikimedia Commons)

In a development that just might make academic cartographers pull out their remaining hair in frustration, Boston’s public schools began using the Peters projection in social studies classes last week. The news coverage (see the Grauniad’s) is the usual straw man argument about the Mercator and the false dichotomy between it and the Peters, as though no other map projections have ever been used. (National Geographic has been using other projections since the 1920s, and currently uses the Winkel tripel. The last time I was at a map store, hardly any of the world maps for sale used the Mercator. See Mark Monmonier’s Rhumb Lines and Map Wars: A Social History of the Mercator Projection, which I reviewed in 2008.)

Regions and Seasons

A new exhibition at the Boston Public Library’s Leventhal Map Center: Regions and Seasons: Mapping Climate Through History. “In this exhibition, you will discover how ‘Venti’ were wind personas who directed ancient ships and ‘Horae’ were goddesses of the seasons who dictated natural order during the 15th-17th centuries, how Enlightenment scientists started to collect and map weather data, and how 19th century geographers reflecting the golden age of thematic cartography created innovative techniques to represent vast amounts of statistical data and developed complex maps furthering our understanding of climatic regions.” Runs through August 27; also online.

Mapping Fossil Sites

The PBDB Navigator is a map-based interface to the Paleobiology Database, which among other things includes the locations of every fossil find. A map of every fossil site seems straightforward enough, but there are hidden depths to this one: you can filter by taxonomy (want to look up the fossil sites for eurypterids or tyrannosaurs? no problem!) or by geologic period, but what’s especially neat is that you can factor in continental drift: when searching by geologic period (the Permian, for example), you can show the continents as they were positioned during that period (see above). More at Popular Mechanics. [Leventhal]

Eleanor Lutz’s Goddesses of Venus

Last year Eleanor Lutz published a medieval map of Mars that, while not strictly medieval in style, was a magnificent application of an ostensibly old aesthetic to a very modern map subject. Now she’s produced a sequel: The Goddesses of Venus is an annotated map that explores the etymological origins of each of Venus’s features, nearly all of which are named after women or female mythological figures. [Kottke]

Previously: ‘Here There Be Robots’: Eleanor Lutz’s Map of Mars.

Rodney W. Shirley

According to a Facebook post by the Washington Map Society’s Bert Johnson, Rodney W. Shirley, the author of several books of cartographic antiquarian research, including The Mapping of the WorldCourtiers and Cannibals, Angels and Amazons, and other titles on early printed maps, died last Saturday. I have not been able to find an obituary or other notice; I will update this post if I do.

A ‘Serio-Comic Map’ for the Modern Age

Last December political cartoonist Andy Davey posted a modern-day caricature map that hearkens back to the eve of the First World War, when such “serio-comic” cartographic portraits were common, but fully up-to-date and relevant to the Trump-Putin era. [Maps on the Web]

Cartographers’ Stories

Daniel Huffman and John Nelson have launched A Cartographer’s Story, a website that collects personal essays from mapmakers.

While our community has a rich culture of sharing project walkthroughs and clever tricks, our colleagues also need to hear about the personal and emotional relationships we have with our maps. We invest ourselves in creating works that are meant to stir the hearts and imaginations of others—and in return our works invest in us. What are your stories? How has mapping moved you or changed you? Did it encourage you through a tough time? Teach you something about yourself? Represent a significant relationship in your life?

Seven stories posted so far; they’re looking for more.