So far the earth has warmed about a degree Fahrenheit globally averaged. That doesn't seem like an enormous amount but it's unlike what we would have expected twenty years ago.

I guess the underlying principle might be, don't make it too easy for them to stereotype you.

[Kids] will grow up into a world that's difficult and wonderful, and they'll make the best of it they can, and hopefully help turn it in the best possible direction.

There are many places where we need to fight important battles to make sure that customers have access to solar.

The Arctic and the Antarctic are melting quickly. We may have waited too long to get started. But this is a day for optimism because the battle is fully joined, and the idea that big oil is unbeatable is no longer true.

I think we need to go straight at the fossil fuel industry.

The polling data shows not an unbelievable level of concern [on climate issue] but a general awareness of this problem. And now I think it's up to all sorts of people who really care about these things to continue on this new ground to try and make this the central political issue it needs to be.