Temperature: Fair?

This Sunday, "60 Minutes" aired a piece on global warming. The piece, which featured correspondent Scott Pelley, largely took the existence of global warming as a given. But there are those who claim that global warming – and, specifically, the notion that humans are responsible for it – is a myth. I asked Pelley why the voices of the skeptics were not heard in the piece.

"There is virtually no disagreement in the scientific community any longer about global warming," he says. "The science that has been done in the last three to five years has been conclusive. We talked to the chairman of the National Academy of Sciences (NOTE: This word was incorrectly transcribed and has been corrected), Ralph Cicerone. Jim Hansen at NASA, who's considered the world's leading expert in climate change. The people in the story, who are well respected in the field. There's just no longer any credible evidence that suggests that, a, the earth is not warming or, b, that greenhouse gasses are not the cause. What you do see in the data again and again and again is this almost lockstep increase between the levels of CO2 and the rise of temperature in the atmosphere. And the climate models that predicted these things happening 15 years ago have proven to be accurate."

"It would be irresponsible of us to go find some scientist somewhere who is not thought of as being eminent in the field and put him on television with these other guys to cast doubt on what they're saying," he continues. "It would be difficult to find a scientist worth his salt in this subject who would suggest this wasn't happening. It would probably be someone whose grant has been funded by someone who finds reducing fossil fuel emissions detrimental to their own interests."

Pelley cites the Michael Crichton novel "State of Fear," which suggests the dangers of global warming are unproved and overstated, as driving the "popular myth" around the issue. Crichton reportedly met with President Bush last year after the president "avidly read" the novel, "fueling a common perception among environmental groups that Crichton's dismissal of global warming…has undermined efforts to pass legislation intended to reduce emissions of carbon dioxide," according to the International Herald Tribune.

But Bush has talked in his State Of The Union address about reducing greenhouse gasses, and the administration spends $5 billion per year researching climate science. The White House's official line is that Bush believes that it is necessary to confront global warming, though the president questions humanity's role in contributing to it.

The Reagan administration, Pelley points out, was initially dead set against acting to reduce chlorofluorocarbons, but as the evidence that they were damaging the environment became overwhelming, it came around. He believes the Bush administration might be reaching a similar "tipping point," thanks to the "remarkable unanimity" among scientists on the impact of global warming.

Still, skeptics remain.

"A favourite ploy by [Anthropogenic Global Warming] alarmists is to repeat ad infinitem that the science about AGW has been settled and that there is consensus among scientists that it is happening and that it will have cataclysmic consequences for our planet," writes Gerrit J. van der Lingen in the National Business Review. "People using these consensus arguments forget that scientific truth is not determined by consensus."