A carbon footprint is the total amount of greenhouse gases (including carbon dioxide and methane) that are generated by our actions.The average carbon footprint for a person in the United States is 16 tons, one of the highest rates in the world.
Globally, the average is closer to 4 tons. To have the best chance of avoiding a 2℃ rise in global temperatures, the average global carbon footprint per year needs to drop under 2 tons by 2050.

Lowering individual carbon footprints from 16 tons to 2 tons doesn’t happen overnight! By making small changes to our actions, like eating less meat, taking less connecting flights and line drying our clothes, we can start making a big difference.

It works by summing up the emissions from all your activities -- everything from what you eat to what setting you wash your clothes with. It's all measured in CO2e, which stands for carbon dioxide equivalent and is a standard unit for measuring carbon footprints. It essentially takes any quantity or type of greenhouse gas and expresses it in the amount of CO2 that would have the equivalent global warming impact. It just allows us to easily compare impacts across different gases.