Movie stars feel good about themselves when they buy "carbon offsets," to cover the CO2 they use when tooling about on their private jets. What they do is pay someone to reduce carbon consumption. I own a tree plantation, and have offers to sell my "carbon offsets" to brokers who would, presumably sell the offsets to a movie star or some other rich person to assuage their guilt over living well. I can't figure out how this system reduces CO2 concentration in the atmosphere since I planted the trees a few years ago for reasons that had nothing to do with CO2. I suspect that most of the other people who could sell carbon offsets are similarly situated. This system, as many have noted, is similar to the Catholic Church selling indulgences during the Middle Ages. It does nothing to reduce bad behavior, but it makes some people rich while making others feel less guilty. Some of the things proposed by Al Gore and other global warmists are just detrimental to society by increasing energy prices and are more like primitive societies tossing virgins into the volcano to avoid angering the gods. The "greens" usually do not attempt to figure out what the optimal solution is: they are absolutists adhering to the "precautionary principle." Here is more discussion in this vein.