Many civilized societies are heavily dependent on maps. News networks produce maps to give viewers a geographical context of a reported event. Individuals use maps to find their way through a building with the help of a building plan or navigate a city using GPS.

However, terrible mistakes can occur with maps. Earlier this year, a Belgian woman who intended to drive 38 miles to a train station was “guided” by her GPS to Zagreb, Croatia, 900 miles away. Most of us may remember seeing maps of electoral results that depict most of the country in red, regardless of the actual election results. 

There are reasons why these things happen with maps, and yet in a society in which people use or encounter maps daily, most people are not aware of why these oddities happen. More importantly, not many people understand what goes into making maps and GPSs.

This semester, I have had the opportunity to take Geography 170, Our Digital Globe: Geographical Information Science and Technology, an introductory course on the art and science of mapmaking taught by professor William Gartner.  This class changed my conception of maps so I no longer see maps as perfectly innocent documents, but instead as liable to abuse. 

There are several major principles that I have come to know and appreciate from this class. An important one is that distortion is inevitable. This is especially true of global maps. Many of us may remember seeing world maps that show that Greenland is three times as large as Australia, even though this is not factually true. The process of producing global maps involve transforming a three dimensional entity into a two dimensional depiction, using what is called a projection – a systematic way of assigning points on the globe to a flat surface with a mathematical formula. There are hundreds of map projections out there, but all of them have distortion in one way or another. A map may preserve area as on the globe, but at the cost making the distorting the shapes of countries, and vice versa. One may ask, “Why not just pick the most accurate projection”? No map projection is “correct.” The point is to choose a projection that accurately depicts what one would like to show.

Another important principle in making maps is selectivity. To say that maps depict phenomena on the earth’s surface is problematic because one can look at a city map that does not show every tree or parking meter. This is an important principle because there are virtually infinite details on Earth, and more detail can appear once we widen our scope of what to include in the map. However, maps cannot simply be a depiction of everything on Earth, for maps will get filled by a dense mass of lines, shapes and colors by which a map becomes comprehensive. This detail is potentially helpful, but not very useful for purposes like navigation. In this case, what to include in a map depends on what are called “map readers.” Having the same representation for a park and a field may be sufficient for map readers concerned about local land use, because what matters is whether an area is developed or undeveloped, but having different representations for parks and fields does matter for birdwatchers.

I cannot sufficiently write about everything I have learned from Geog 170, and it is only an introductory course. The necessary selectivity and distortion involved in mapmaking means that mapmaking involves decision-making. With each decision there are trade-offs, highlighting one thing at the expense of downplaying another. The point is not to see this as an impotency of cartography. What matters is whether the information and perspective sacrificed in making a map is justified.  This leaves cartographers and their clients in the position of authority, because they can vary the message of a map even with the same type of data. Thus, a map is not simply a factual graphical document, but an instrument of argument.

I strongly encourage students to take Geog 170 as a way of enlightening themselves about this piece of paper that shapes our conception of the world around us. If you notice, most of the maps that we encounter daily do not even have the map author’s name, but maps do have human authors, authors who make deliberate decisions and may not be free from bias. At least by recognizing what goes into making maps and the trade-offs involved, we can be more critical map readers and not blindly trust in maps and GPSs. 

Heikal Badrulhisham ([email protected]) is a freshman majoring in economics.