Possibly the greatest con in the history of mankind; a theory made up by Al Gore and liberal scientists to try to tell you that you are killing the planet and should be ashamed of your lifestyle. After you are completely convinced of this, Al Gore then tries to guilt you into giving him money to buy bullshit "carbon credits" from his website. Al uses this money to buy more private jets and 20,000 square foot homes. It is also used as an excuse by liberal politicians to raise taxes on every citizen in the United States, even though there's absolutely no scientific basis to suggest that would lower carbon emissions.
Bob: What are you doing?
Joe: Buying more carbon credits from Al Gore; I drove my SUV 20 miles today!
Bob: Dude, you know global warming is complete BS, right?