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.

There is a tendency at every important but difficult crossroad to pretend that it's not really there.

All the things that we've done as a species have had a limited scope. We're talking about melting the ice caps, raising the level of the seas dramatically, changing the distribution of every other species on Earth, perhaps wiping out one-third or half of them. The changes at work are geologic in scale. The level of change required to deal with it is enormous, too. It will require change in every country. It will require a degree of global cooperation that we haven't seen before.

Profiting from companies that are overloading the atmosphere with carbon and changing the atmosphere is wrong.

The most blatant examples are increased power and frequency in hurricanes and the increased depth and frequency of heat waves.

When we think about global warming at all, the arguments tend to be ideological, theological and economic.

Do I think that people should in the best of all possible worlds have to go to jail for wanting the US government to pay attention to the warnings of scientists about climate change? Not really. I mean, in a rational world, if all the scientists said, "The worst thing that ever happened is about to happen and here's what you should do to stop it," you would expect any rational system to say, "Oh, sure, OK, let's do something about it." But that's not the world we live in. In the world we live in, you do need people willing to stand up, fight, march and sometimes go to jail.