The fight around climate change, which I've spent my life on, is somewhat more difficult than gay marriages because no one makes trillions of dollars a year being a bigot, and that's how much the fossil-fuel industry pulls in pumping carbon into the air. But the principle is the same, I think.

All the science in the last few years, or almost all of it, really serves to show that the [climate] effects are larger and more rapid than we had thought even a decade ago.

everyone knows, at some level, that the sharp line between "good weather" and "bad weather" is a fiction, that we need rain as surely as we need sun.

There's no huge mystery. If you dig up huge amounts of carbon, huge amounts of ancient biology, hundreds of millions of year's worth of ancient biology, and flush it into the atmosphere in a matter of decades, then it stands to reason that we're going to have enormous effects, and now we can see those effects all around us.

All the signs of incipient activism and uprising, from Tahrir square to Zuccotti Park to [the recent] shutdown of the Internet to protest web censorship. People are getting smart and getting connected.

It was huge mistake to avoid working with the rest of the world because (a) we're the largest source of the problem: 4% of us who are in the U.S. produce 25% of the world's carbon dioxide.

Most of the men and women who vote in Congress each year to continue subsidies have taken campaign donations from big energy companies.