> Surely this can't be right, because if it were, air conditioning (the normal everyday kind) would be impossible, right? Keep in mind that air conditioners ar

> Surely this can't be right, because if it were, air conditioning (the normal everyday kind) would be impossible, right? Keep in mind that air conditioners are net generators of heat. The work they do moving heat around generates more heat. If you build a sealed sphere 100 feet in diameter around an air conditioner and plug it in, the air inside the sphere will heat up. This is why you cannot just open your refrigerator door to cool your house. Earth's atmosphere is warmer today around cities where a lot of air conditioners are in use. (Although excess CO2 has a much bigger effect of course.)