The term "carbon footprint"

[One Earth]

I hear the term "carbon footprint" frequently, but I have never really heard the definition of that term, and I don't have an understanding of this concept. Can someone explain?

[EcoChic]

I understand carbon footprint to mean your total negative environmental impact. That includes how much gas, water, and other natural resources you use, as well as any pollution you create.

[Greenerly]

Carbon footprint, if I'm not mistaken, is the amount of CO2 that your household produces per certain period of time. Apparently this can be calculated. It's interesting that there is absolutely no proof that human produced CO2 causes global warming, which brings me to entirely new issue; if they want to tax us for carbon production wouldn't that be a criminal act by the government?