Katrina opened a good door and Al Gore went through it with his movie.

I think we need to think of lots of ways to communicate. And we tried some at 350. We organised what they called the largest art project in the planet's history. We do a lot with art and music and things.

If the Holy Spirit is capable of the heavy lifting required to get Pat Robertson to change his mind, then that strikes me as a very good sign.

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.

It drives me crazy to see so much of this planet's life so casually endangered. The first steps are so easy (drive smaller cars, for instance) that it's very hard to understand why we haven't taken them. But I know that this is the issue our generation will be judged by.

We'd won the argument 15 years before, we were just losing the fight. And so it became clear to some of us that we would need to organise to fight, that we weren't going to win.

Between [Speaker of the House] Paul Ryan, [Senate Majority Leader] Mitch McConnell, and Donald Trump's team, I don't see a lot of openings for making real progress.