OK, I’ll bite. What the hell is my carbon footprint?

Wait, you may be thinking, I’m not like that. But even if you’re not the kind of person who would just dump all your trash on the ground in a park for fun, your actions and energy use are taking a toll on the planet via invisible pollutants, says Charles Barnhart, assistant professor at the Institute for Energy Studies at Western Washington University. “Just as a park is a shared resource, the entire atmosphere is a shared resource.”