Over the course of the last two weeks, two scientists — James E. Hansen of Columbia University and Richard A. Muller at the University of California, Berkeley — took to the pages of two prominent American newspapers to present new and compelling evidence that climate change is real, that it is driven overwhelmingly by human activity, and that its dire effects are already upon us.
And then nothing happened.
“Call me a converted skeptic,” Muller wrote in an essay published July 28 in The New York Times, citing research posted, though not peer-reviewed, to the website of the Berkeley Earth Surface Temperature initiative. “Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. 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.”
Hansen’s turn came a week later. “Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change,” Hansen declared in The Washington Post on Sunday, citing peer-reviewed work published the following day in the Proceedings of the National Academy of Sciences. “To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.”