So much for the “yellow peril.” It was red all over. During the Cold War, we were used to seeing lots of red ink spilled across maps, portending the onslaught of the communist hordes from the east. You can check out this post at strangemaps that adds some “perspective” to the Red Menace.
Here, I’m talking about a different sort of red, the type that signals danger, alert, alarm, something bad happening! Color is used in maps for all sorts of reasons, including just making them easier to read, but often, in “thematic maps,” i.e., maps that convey information and data about a particular topic, the colors are related to a scale of values that is described in a key, or legend. The image below is from a recent article in the New York Times Science section about the mapping of the impact of humans on the oceans of the world. This map shows the distribution of shipping lanes over the seas.
Notice that red is the highest value, i.e., “most impact.” Clearly, that’s bad, isn’t it? But…how are we to know? Compared to what? Maybe it’s all horrible. Maybe none of it is. Maybe it doesn’t matter. I’m not saying that’s true, but the map doesn’t illuminate this point, while it does give the clear impression, with all that red splotched around, that humans are just mucking up the oceans everywhere!
Well, not quite everywhere – the southern hemisphere looks okay. What if we had chosen a projection of the earth like this one? The effect would be quite different, less alarming, less informative?
Maps tell stories, and the mapmaker decides what to emphasize and what to downplay…suppress. Color and cartographic projection are part of that storytelling. No problem here, except that for some reason, people tend, I think, to regard maps as purely scientific documents that are totally precise and objective.
One could see the map in the NYTimes, and the others to be found at that link, as part of a sustained effort to propagandize for the view that the earth is fragile, in need of support and tender care, and that the cause of the problem is the brutish, unthinking behavior of stupid, destructive humans. Is this a true story or a myth?