In trying to solve the world's energy problems on the back of a napkin (see blog), I think I figured this global warming thing out. Mind you, I don't believe in human-caused global warming; but this one's a little more generalized. Basically, the sun and the earth are the same; the earth's a lot dimmer, but it radiates thermal energy out into the universe, and has struck an equilibrium with input (from the sun) versus output. Plants store thermal energy; bacteria and animals eat plants and release thermal energy. Well, every machine running on electricity also releases thermal energy. Whether we burn biofuels or throw up solar panels, we're absorbing energy from the sun that's normally reflected wholesale back to space and/or releasing it faster into the ambient environment than useful (i.e. burning plants in 30 seconds, rather than letting them decay in 3 months). With all the extra absorbed and wholesale-released heat, the equilibrium point shifts upwards, and the earth maintains a higher temperature-- it gets hotter! It gets hotter with every man, animal, and machine that walks the surface of this damn planet!