My position on "global warming" keeps evolving (as should every sensible person's, as new evidence comes in). I started out skeptical (I start out skeptical about everything...I'm a conservative) but when Ron Bailey of Reason decided the evidence was conclusive, I flipped. Also, I read "The Skeptical Environmentalist" by Bjorn Lomborg, which surprisingly accepts the IPCC estimates on global warming but disputes the cost-benefit analysis that led to Kyoto.
Since then, several prominent people who were on the global warming side have switched back to being skeptics. I don't know whether to believe them or not but my basic position remains about the same.
- the Earth's temperature is currently in a warming phase (though it seem so have stalled in the last decade) (FACT)
- CO2 concentrations are much higher than in recent history (FACT)
- temperature and CO2 have risen and fallen in sync based on ice core samples (FACT)
- ...however, the temperature rises first and CO2 goes up about 800 years later (FACT)
- CO2 is a greenhouse gas that, in the absence of side effects, would lead to a 1-2 degree rise in temperature by 2100 (FACT)
- the side effects of a rise in CO2 are a rise in water vapour, which speeds up the warming, and a rise in cloud cover, which slows it down (COMPUTER MODELS INCONCLUSIVE)
- cost of a 2 degree rise in CO2 is almost certainly less than the cost of Kyoto style controls (MANY PEOPLE'S OPINION, INCLUDING MINE)
My conclusion hasn't changed: We should take modest and inexpensive steps to begin to control the level of CO2. The most important one being to encourage the building of nuclear plants, which do not produces CO2. A much better reason for supporting this goal than the phony global warming "crisis" is that it would reduce our dependence on foreign oil and stop sending trillions of dollars to middle eastern dictatorships.
I favour research into geo-engineering schemes that will give mankind the ability to manage the planet's temperature in the future whether it is going up or down. We are overdue for an ice age and all scientists agree that an ice age would be several orders of magnitude more devastating than global warming. Civilization developed in the interregnum between ice ages.
I write this from Windsor, Ontario. In the last ice age, Windsor was under about a kilometer of ice. For Canada, an ice age would be an extinction level event.