There are good people, who are in politics - in both parties - who hold this at arm's length, because if they acknowledge it and recognize it, then the moral imperative to make big changes is inescapable.

Traditionally the United States has been the natural leader of the world. That's not just pride as an American speaking; it's just the reality. Without the U.S. being involved in Paris Climate Agreement, it's hard for the world community to move forward as effectively.

I have faith in the United States and our ability to make good decisions based on the facts.

Most people talk as if Miami and Bangladesh still have a chance of surviving: most of the scientists I spoke with assume we'll lose them within the century, even if we stop burning fossil fuel in the next decade.

The task of saving the earth's environment must and will become the central organizing principle of the post-Cold War world.

I take no pleasure in the fact that the scientific predictions I’ve relayed to popular audiences turn out to be true.

A lot of people go straight from denial to despair without pausing in the middle and doing something about it.