An analysis of temperature data since 1500 all but rules out the possibility that global warming in the industrial era is just a natural fluctuation in the earth's climate, according to a new study by McGill University physics professor Shaun Lovejoy."This study will be a blow to any remaining climate-change deniers," Lovejoy says. "Their two most convincing arguments - that the warming is natural in origin, and that the computer models are wrong - are either directly contradicted by this analysis, or simply do not apply to it."
Lovejoy's study applies statistical methodology to determine the probability that global warming since 1880 is due to natural variability. His conclusion: the natural-warming hypothesis may be ruled out "with confidence levels great than 99%, and most likely greater than 99.9%."
To assess the natural variability before much human interference, the new study uses "multi-proxy climate reconstructions" developed by scientists in recent years to estimate historical temperatures, as well as fluctuation-analysis techniques from nonlinear geophysics. The climate reconstructions take into account a variety of gauges found in nature, such as tree rings, ice cores, and lake sediments. And the fluctuation-analysis techniques make it possible to understand the temperature variations over wide ranges of time scales.http://www.sciencedaily.com/releases...0411153453.htmFor the industrial era, Lovejoy's analysis uses carbon-dioxide from the burning of fossil fuels as a proxy for all man-made climate influences - a simplification justified by the tight relationship between global economic activity and the emission of greenhouse gases and particulate pollution, he says. "This allows the new approach to implicitly include the cooling effects of particulate pollution that are still poorly quantified in computer models," he adds.
I don't want to quote much more, as it's a relatively short article, and I'm not sure how much discussion this is really going to generate considering the relatively liberal nature of the forum, but it is great to see the data supporting a theory that's been held by most scientists, and rejected by a pretty vocal minority for a while now.
Hard to argue with the math here.