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

The golden thread of reason that used to be stretched taut to mark the boundary between the known and the unknown is now routinely disrespected.

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 naturally an optimist, but my basis for hope is rooted in my understanding of human nature.

Every day we put another 110 million tons of global warming pollution into the sky as if it's an open sewer, and it's still building up. And the scientists tell us it's a race against time. We've stabilized emissions globally now for the last three years, but they need to start coming down quickly. We've got the momentum, we've got the wind in our sails, we're gonna win this.

I have a personal staff that helps me scour the internet and other media for the latest scientific peer-reviewed findings, the latest examples of climate-related extreme weather events, and the latest examples of progress. The world is in the midst of a sustainability revolution that has the scope of the industrial revolution, but with the speed of the digital revolution. That's not enough without new laws and the right kind of political leadership. But it does give us a base from which to build a movement that will save us from the most catastrophic consequences of the climate crisis.

Scientists with access to data from Navy submarines traversing underneath the North polar ice cap have warned that there is now a 75 percent chance that within five years the entire ice cap will completely disappear during the summer months.