Solar power seems to be truly bipartisan in its appeal.

The idea that China and India will just abandon climate action is not true, because they're doing it for more reasons than we are.

To me, it's more important to take the 60-70% of people who really understand that there's a problem [of climate change] and get some percentage of them active than to try and stamp out the last embers of pre-scientific thought.

The thing about global warming is that you can address it on a great number of levels - in fact you have to.

When you are in a hole, stop digging!

There is no real scientific debate over what is happening; of course there is debate over exactly how it is going to play out in the decades ahead, because this is a large experiment that we haven't done before, and no one knows precisely how one can ever precisely predict what effects this heat will have. But all the science in the last few years, or almost all of it, really serves to show that the effects are larger and more rapid than we had thought even a decade ago.

I think [George W.] Bush has done nothing right about global warming.