Greenland and the Mercator Projection

If Donald Trump has a world map on his office wall, I’ll bet it is a traditional one based on the Mercator Projection. Perhaps with some sharpie modifications.

Gerardus Mercator, a Flemish geographer, developed his famous mapping methodology in 1569 and it remains one of the most common mapping formats. You’ll recognize it instantly for two reasons. First, the lines of longitude (up and down) are straight and vertical, as if the world were a cylinder rather than a sphere. This is actually useful as it enables navigators to plot rhumb-lines (which, incidentally, yield the typically curved “Great Circle” airline routes.)

The second standout feature of a Mercator map is also its downfall. Because Mercator effectively turned the globe into a vertical cylinder, the closer you get to the poles, the greater the distortion of features. This is why Canada, which is about 1.3 times the size of Australia, appears on Mercator to be three or four times larger. Similarly, Africa appears significantly smaller than North America, although the opposite is actually true.

And Greenland! Mercator makes Greenland out to be continental in size, larger than Australia, Africa, or South America. In reality, Greenland is about the same actual size as Saudi Arabia or Mexico.

So if the Donald has a Mercator projection map on his wall, it’s easy to understand his lust to acquire both Canada and Greenland. Together with the USA, they look like half the world, comparable to all of Eurasia. Why would the Orange One not want to possess all that? When you’re famous, you know…

But let’s talk about something less unpleasant. Let’s consider the lessons of the Mercator projection. First, that it was a simple solution to a vexing problem: how to stretch the skin of a globe across a flat surface. Mercator accomplished this, with the added benefit of simplifying navigation.

He also undoubtedly understood the limitations of his methodology. Unfortunately, most of the rest of us don’t. We’ve grown up with the ubiquitous Mercator world maps, thinking that they accurately represent the earth’s surface. They don’t, and weren’t meant to. But in our mind’s eye, Greenland is as big as Africa. That’s our operating assumption, and not a trivial error.

Our belief systems and our approach to many of life’s issues are often founded upon “facts” which are demonstrably wrong and generally easy enough to rebut with just a few minutes of questioning and critical thinking. Few readers still believe in a literal Santa Claus or Easter Bunny, but many of us, for example, believe that most welfare recipients are fully capable of getting a well-paying job if they weren’t so lazy. Just as Mercator is dead accurate at the equator, so such suppositions are accurate within a small band of examples, but wildly inaccurate the further you get from a handful of proof-cases.

One of the reasons my book is taking so long to finish is that I keep running into inconvenient data, forcing me to re-examine assumptions, sometimes re-writing entire chapters. It’s frustrating, but necessary, if I expect to be taken seriously.

Our Mercator assumptions are often handy in certain everyday situations where we want a “quick and dirty” solution, but when it’s life of death, credible or not, useful or dangerous, we need to question our inputs to ensure that our outputs are reliable.

The other takeaway from all this is that there is no perfect way to spread the surface of a sphere across a flat surface. If I were still teaching geography, I would give the kids beach balls and have them try to spread them across a table. They would soon learn that there just is no fully effective method.

Our lives are like that, too. As much as we may wish for perfection, in many cases it just ain’t gonna happen. Our bodies and our minds and our circumstances are full of hundreds of imperfections (well, in my case for sure, maybe not yours) and we do well to accept working solutions which we know are imperfect, but in a limited lifetime a far more pragmatic approach than getting all upset trying to turn that darned beachball into a tablecloth.