Mitt Romney is well-known as someone who will shamelessly change his position for political expediency, and now he’s applying his famous mental gymnastics to the issue of global warming.

The details are here, but basically he’s realizing that his rational statement on climate change in the past are not doing him any good in a GOP primary dominated by voters who hate science.

This is pretty interesting, as all of the global warming skeptics will now have to face this study from a former skeptic.

Climate change deniers thought they had an ally in Richard Muller, a popular physics professor at UC Berkeley.

Muller didn’t reject climate science per se, but he was a skeptic, and a convenient one for big polluters and conservative anti-environmentalists — until Muller put their money where his mouth was, and launched the Berkeley Earth Surface Temperature project, in part with a grant from the Charles G. Koch foundation.

After extensive study, he’s concluded that the existing science was right all along — that the earth’s surface is warming, at an accelerating rate. But instead of second-guessing themselves, his erstwhile allies of convenience are now abandoning him.

“When we began our study, we felt that skeptics had raised legitimate issues, and we didn’t know what we’d find,” Muller wrote in a Friday Wall Street Journal op-ed. “Our results turned out to be close to those published by prior groups. We think that means that those groups had truly been very careful in their work, despite their inability to convince some skeptics of that. They managed to avoid bias in their data selection, homogenization and other corrections. Global warming is real. Perhaps our results will help cool this portion of the climate debate.”

This does not speak to the issue of whether humans are causing the warming, but it’s another persuasive set of data on this issue of warming itself.