The old joke is 100% correct in regard to the ecoparanoid AGW obsession.
Con man:(addressing mark) Elephants are very dangerous. I can provide some elephant repellant to you for a very fair price
Mark: (outraged) What the Hell are you talking about? There haven't been any elephants in this part of the world for 10,000 years!!
Con Man: (without missing a beat) See how GOOD it works?