What we take for granted might not be here for our children.

We can't negotiate the facts. We can't negotiate the truth about the situation. And for those who are too fearful to finish, it can be done and must be done. Make sure we succeed, . . . It is wrong for this generation to destroy the habitability of our planet and ruin the prospects of every future generation.

We sometimes emphasize the danger in a crisis without focusing on the opportunities that are there.

It should be lifted above partisanship because it's a question of survival. It's a moral issue.

I doubt nuclear power will play a much larger role than it does now.

Most people in politics draw energy from backslapping and shaking hands and all that. I draw energy from discussing ideas.

The entire North Polar ice cap is disappearing before our very eyes. It's been the size of the continental United States for the last 3 million years and now 40 percent is gone and the rest of it is going.