The United States puts out as much greenhouse gas emissions as the UK, Brazil and China combined. That’s a pretty damning statistic in itself, and it’s something people should think about. But there’s also something Science magazine and the World Research Institute should think about: bad infographics.

Unfortunately, the Science article that contains this map is behind a pay wall, and the Climate Analysis Indicators Tool requires registration and possibly affiliation with an organization. In any case, very few people are going to take the extra steps to register and sift through the raw data to figure out what the map means. That’s the whole point of infographics like these—to distill mountains of data and highlight the main findings. The map is supposed to give you an idea of how the United States stacks up against other countries when it comes to emissions.
So tell me this: what fraction of the United States’ emissions does Brazil represent?
Not so easy to figure out, is it? Here’s some questions that pop into my mind when I see this. First, the map is split into states, and each nation’s footprint fits neatly inside state lines. Does that mean that Brazil’s emissions footprint is equal to exactly the emissions from the specific midwestern states it covers? Or is it equal to the fraction of the United States represented by the area those states cover? After all, the World Research Institute claims California is one of the top 30 emitters in the world, and it’s included in the UK’s footprint. Comparatively, the midwestern states probably produce fewer emissions (based solely on my assumption that population density is lower and thus emissions are lower—I may very well be wrong, but that’s somewhat besides the point). So, even though Brazil’s footprint appears larger on the map, is its emissions footprint perhaps smaller than that of the UK, whose footprint includes California? Who knows? The map gives you no way to tell.
That one issue makes the whole map harder to understand. When China is shown to take up more than half of the United States, does that actually mean China produces half the emissions of the United States? But China’s footprint includes all of the high-emission states except California, so does China actually produce substantially more? What about Canada, stuck in the dense northwestern states. How does its emissions footprint compare to, say, South Korea? Are they, in fact, roughly equal? Are they each only about a fifth of Brazil’s footprint? The map implies relationships that may or may not be there; it’s ambiguous, a very bad thing when you’re trying to clarify a complicated issue.
It’s nice to be able to slap together some fancy graphics in order to make a point, but this is one of those cases where a simple bar chart would’ve told you so much more about where each country stands compared to the States. All I get out of this graphic is the message that the States produces a lot of emissions—an important message, but blindingly obvious. Once you get past that revelation, the map gives you little idea of just how bad things are. Since that’s sort of the whole point of the map, it can be classified a failure.