Acclaimed skeptic Michael Shermer, head of the Skeptic Society among other things, has a recent column in Scientific American in which he admits that is is now won over by the evidence for anthropogenic climate change [LINK]. Skepticism is very good, and I think most scientists are skeptics at heart. At this point though, people who are still on the fence about human-induced climate change are either turning a blind eye or are being pulled by non-objective forces toward the other side. Apparently Shermer was just turning a blind eye.
So what was it that made Shermer finally find his way to the side of science on this issue? Did he get a preview of the IPCC 4th Assessment Report? Did he take a critical look at the scientific literature? Did he visit NCAR and talk with leading scientists in the area? No, he saw Al Gore's presentation. Okay, I also saw it, and I must say it is very good. But Shermer says it is "based on the recent documentary film about his work in this area, An Inconvenient Truth. The striking before-and-after photographs showing the disappearance of glaciers around the world shocked me out of my doubting stance." Well, it is an important part of the documentary (and book), An Inconvenient Truth, but it is not Al Gore's work. That is an incredibly inaccurate statement. I'm a big Al Gore fan, but he's not a scientist. Giving a summary of hundreds of other people's work can lead to a significant contribution in a field, but that would be a technical review, this is really just a public outreach project. And to be convinced by before and after photos is a naive approach to understanding an incredibly complex phenomenon. The photos are impressive, no doubt, but taken out of context, such photos can also be extremely misleading. For example, until the last few years some mountain glaciers in North America and Europe were growing, after having shrunk in the middle of the 20th C. The photos are impressive, showing giant sheets of ice coming down the mountain year after year. However it wasn't because the world was cooling, but because of local effects. Today we can look at most glaciers and feel confident that they are receding because of global warming, but it is only because we have the cumulative effects of many glacier observations. I'm glad Shermer has decided to use science and logic on this issue, but it is too bad he had to be convinced by a flashy powerpoint presentation instead of the actual scientific evidence.