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.

There's no such thing as clean coal. It's non-existent. Theoretically, it might be possible, many years from now, to come up with a way to clean it as it's burnt. But there's not a single demonstration project in the United States. [...] Clean coal doesn't exist.

I'm not a vegetarian, but I have cut back sharply on the meat that I eat.

Our way of life is at stake, our grandchildren are at stake, the future of civilization is at stake.

It's as if we think the laws of physics are subject to debate and amendment and political contributions can sway the laws of physics.

The truth is that we're at a critical juncture in the history of our species and if we don't act soon, we could inhabit a world we don't recognize anymore. But the most important truth is that we are capable of stopping climate change before the worst of its consequences are locked in. The solutions exist - all we need is the will to do something about it.

Every nation has a moral obligation to safeguard the future.