Most people I meet outside Clark express surprise or confusion when I say that I study Geographic Information Systems. At Clark, no one bats an eye, as Geography is actually a very popular major here. Some people might ask me what GIS is, and then I have to say that I basically make maps.
Something a lot of people ask me when they hear that is, “So apparently the world map is biased to make Europe look bigger than it actually is”. For those who don’t know, the most popular map of the world uses a projection called the Mercator projection. A projection is used when displaying a three dimensional spheroid into a flat map. One of the first things taught in the Intro to GIS class, and then re-taught at all successive GIS classes, is that during this process, distortions are bound to happen, as a 3D surface cannot be made into a flat surface without losing certain properties – direction, shape, distance, or contiguity.
Three different types of projections
(Source)
And that’s where the Mercator gains its popularity. First created in the 1950’s, it gained popularity as the map used by sailors for navigation, because of its ability to preserve direction. What this means is that in maps using the Mercator projection, the angles between objects is preserved accurately. If your map says that the road turns at a certain point, it will too in real life. The trade-off for this is that the shapes of countries relative to each other get heavily distorted.
To understand why, we need to take a look at how map projections work. The Mercator uses something called a ‘cylindrical projection’. Imagine a glass globe, with a light source shining inside it. Now if a flat piece of paper were to be wrapped around the glass globe emanating light, the shadows of the countries falling on the paper would be the map. It becomes clear that the middle of the piece of paper, which touches the outer edge of the globe in a tangent, is where the countries appear smallest. This line falls on the equator in a Mercator projection, making the countries on the equator smaller, such as Africa. Farther away from the equator, the shapes become more distorted, which is why the countries of the Northern hemisphere, such as Greenland or Europe appear much larger in relation of the equator.
How a projection works
This might give the idea the Mercator projection’s dominance over hundreds of other projections is due to a bias towards the global North. Europe had dominated trade during the colonial years, and so the map that was used for navigation became the most prominent one. However, even today, it is used for the same purposes of navigation, which leads to its persistence in the general psyche. Google Maps uses a variation of the Mercator, flight systems around the world use its variations, and the NASA’s LANDSAT satellite that maps the entire world uses a projection system derived from the Mercator.
We use maps most commonly for navigation, which is why the Mercator, with its functionality is the preferred map. But those who work with maps beyond that of the purposes of navigation choose from a plethora of other projection. Researchers on the North Pole would use an azimuthal projection, someone looking at the density of a particular factor over space would be more likely to use an Equal-area projection. But for someone who would like to break with the norms of how the world is portrayed today, there exists a Compromise Projection. This projection makes some compromises on size, shape, direction and contiguity, but shows the world closest to how it appears on a globe – without any blatant distortions. Whether or not this Compromise Projection should become the standard global map is the cause of many debates.
Compromise map
