Romney Skeptical on Human Role in Climate

Mitt Romney's views on global warming are back in the news. This week, he reaffirmed his skepticism about humans contributing to climate change. CBS News detects a "rightward shift" as the campaign goes on, and both Democrats and Rick Perry agree, notes CNN. Judge for yourself, as Politico rounds up some of his statements on the subject:

• Thursday: "My view is that we don’t know what’s causing climate change on this planet. And the idea of spending trillions and trillions of dollars to try to reduce CO2 emissions is not the right course for us."
• August: "Do I think the world's getting hotter? Yeah, I don't know that, but I think that it is. I don't know if it's mostly caused by humans."

• June: "I don't speak for the scientific community, of course, but I believe the world is getting warmer, and I believe that humans have contributed to that. ... I don't know how much our contribution is to that, because I know there's been periods of greater heat and warmth than in the past, but I believe we contribute to that. And so I think it's important for us to reduce our emissions of pollutants and greenhouse gases that may well be significant contributors to the climate change and global warming that you're seeing."
• His 2010 book No Apology: "I believe that climate change is occurring—the reduction in the size of global ice caps is hard to ignore. I also believe that human activity is a contributing factor. I am uncertain how much of the warming, however, is attributable to man and how much is attributable to factors out of our control."

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