[Political actions] has to happen on the local and state level; we have to convince our cities to join the growing number of more than 200 American cities who have signed on to the mayor's climate campaign.

The world is on fire, and I'm doing my best to help steer the firetruck.

There is basically no one not on the payroll of Exxon Mobil or coal companies who any longer contend that this is not something to worry about.

Everybody was cratered after Copenhagen. If the movie had worked the way that it should have, if it had been scripted by Holywood, the world would have come together and addressed the biggest problem it ever had faced and delegates would have embraced each other, and it all would have been a good happy scene instead of the complete farce and debacle that it turned into - maybe in certain ways, an absolute low point for human diplomacy.

We also have to engage - and I think this is important - in national politics because there is no way to address questions of this scale in the short time that we have to address them without engaging in real political change.

When you go to China and the developing world, people understand more clearly the dangers that are coming at them because they're living closer to the margin. They don't have any of the false sense of invulnerability that Americans have. People from developing countries also feel that it's their right, if you're talking in terms of justice, to use fossil fuels like we did for a hundred years to get rich. It's hard for them to give up that vision.

Permafrost in the soil [is melting], in the boreal and arctic areas in the world, and, probably even more alarming in the last six or eight months, the data on what is happening to the ice shelves in Greenland and the west Antarctic has begun to cause people to radically reassess the earlier conviction that those ice shelves were stable on a kind of century-long time scale.