(Roughly) Daily

A map’s most basic assumption is a question of orientation (or persective, if you will). For most of us, “up” on a map is north… but it needn’t be– and in Australia, it often isn’t…

Perhaps more impactfully, there’s another matter of perspective: the question of a map’s projection (of areas on a sphere onto a plane). A couple of years ago, (R)D featured The True Size (source of the image at the top), which noted that…

It is hard to represent our spherical world on flat piece of paper. Cartographers use something called a “projection” to morph the globe into 2D map. The most popular of these is the Mercator projection.

Every map projection introduces distortion, and each has its own set of problems. One of the most common criticisms of the Mercator map is that it exaggerates the size of countries nearer the poles (US, Russia, Europe), while downplaying the size of those near the equator (the African Continent). On the Mercator projection Greenland appears to be roughly the same size as Africa. In reality, Greenland is 0.8 million sq. miles and Africa is 11.6 million sq. miles, nearly 14 and a half times larger…

Maps are in the news again, and for exactly that reason. As the estimable Frank Jacobs reports in Big Think, The African Union is arguing that the Mercator projection distorts the continent, both in size and global attention…

On a world map in the Mercator projection, Russia appears larger than Africa. In fact, Africa (11.7 million sq mi, 30.4 million km²) is nearly twice as large as Russia (6.6 million sq mi, 17.1 million km²). Africa has finally had enough.

“(Mercator) is the world’s longest misinformation and disinformation campaign, and it just simply has to stop,” Moky Makura, executive director of advocacy group Africa No Filter, told Reuters. The group champions the introduction of the Equal Earth projection, which aims to give Africa its magnitudinal due.

The African Union (AU) — the association bringing together all of Africa’s 55 countries — has joined Correct the Map, a campaign that urges national governments and international organizations such as the UN or the World Bank to replace Mercator with Equal Earth [here]…

… “Maps are not neutral,” Fara Ndiaye, the co-founder of Speak Up Africa, told The Washington Post. “They were never meant to be. They shape how we learn, how we imagine power, how we see ourselves.”

But, as Jacobs notes, the switch could be tricky…

In 1569, Flemish mapmaker Geert De Cremer — known by his Latinized name as Gerardus Mercator — introduced a map projection that revolutionized navigation. Simply put: a straight line on a Mercator map is a straight line at sea.

That’s not as obvious as it might seem. If you flatten a three-dimensional object, such as the Earth, onto a two-dimensional surface, like a map, you’ll inevitably create some distortion.

Mercator’s radical solution was to reduce directional distortion to zero: His projection maintains accurate angles and directions. That so-called conformal map projection made life (a little bit) easier for the ships swarming out all over the world in the Age of Sail.

But that decision came with a trade-off: It grossly inflated the size of land masses closer to the poles…

… traditions are hard to break. Case in point: The AU itself is still using Mercator for some of the maps on its websites. But secondly, and most importantly, maps aren’t about fairness; they’re about function. Despite its advanced age, the Mercator projection has an in-built advantage over most others.

Mercator’s rectangular grid wasn’t just instrumental for 19th-century whaling vessels tracking their prey; it’s just as useful for 21st-century digital cartography. All those straight angles make Mercator the projection of choice for zoomable maps…

Eminently worth reading in full: “Africa wants its true size on the world map,” from @bigthink.com.

See also: “The True Size of Africa” (an inspiration for The True Size)

* popular idiom

###

As we scrutinize scale, we might spare a thought for Joseph Nicollet; he died on this date in 1843. A  geographer, cartographer, astronomer, and mathematician, he is best known for mapping the Upper Mississippi River basin during the 1830s.

Nicollet’s maps were among the most accurate of the time, correcting errors made by Zebulon Pike, and they provided the basis for all subsequent maps of the American interior. They were also among the first to depict elevation by hachuring and the only maps to use regional Native American placenames.

Nicollet is memorialized in the names of several places in the region he explored, including Nicollet Island, Nicollet Avenue in Minneapolis, Nicollet County, and the city of Nicollet, all located in Minnesota.

source