Former climate skeptic says humans driving crisis

Physics professor Richard Muller, chair of the Berkeley Earth Surface Temperature project.
Physics professor Richard Muller, chair of the Berkeley Earth Surface Temperature project.
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When it comes to the politics of climate change, it’s hard not to enjoy the story of Richard Muller, a Berkeley physics professor.

Not long after the so-called “Climategate” story, Muller, a self-proclaimed skeptic of global warming, created the Berkeley Earth Surface Temperature project to examine all of the available data, and resolve any lingering doubts. Conservatives were thrilled and quickly proclaimed they would accept whatever results Muller came up with. The Koch Foundation even gave Muller’s project $150,000.

To put it mildly, the right was crushed last fall when Muller published the results of his research: the climate scientists have been right all along. “Global warming,” Muller concluded, “is real.”

That was in October. Over the weekend, Muller went even further in the New York Times, calling himself “a converted skeptic,” and highlighting some additional findings of his research.

Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: Humans are almost entirely the cause.

My total turnaround, in such a short time, is the result of careful and objective analysis by the Berkeley Earth Surface Temperature project, which I founded with my daughter Elizabeth. Our results show that the average temperature of the earth’s land has risen by two and a half degrees Fahrenheit over the past 250 years, including an increase of one and a half degrees over the most recent 50 years. Moreover, it appears likely that essentially all of this increase results from the human emission of greenhouse gases.

These findings are stronger than those of the Intergovernmental Panel on Climate Change, the United Nations group that defines the scientific and diplomatic consensus on global warming.

Remember, Muller’s research was intended to prove the opposite. The physicist and his team even took the most common arguments raised by climate deniers, putting them to the test to see if skeptics’ claims had merit. It’s why the Kochs got out their checkbook in the first place.

But Muller is now telling his benefactors what they don’t want to hear (a.k.a., the truth): the climate crisis is real and it’s caused by human activity. Whether humanity chooses to deal with the reality of the crisis remains to be seen, but we can’t say we weren’t warned.