We've built a new Earth. It's not as nice as the old one; it's the greatest mistake humans have ever made, one that we will pay for literally forever.

Climate change is a huge problem, an almost insoluble problem.

Between [Speaker of the House] Paul Ryan, [Senate Majority Leader] Mitch McConnell, and Donald Trump's team, I don't see a lot of openings for making real progress.

In the last two years 24 countries have set new all-time temperature records. We've seen flooding on an epic scale in every continent .

In 50 years, no one will care about the fiscal cliff or the Euro crisis. They'll just ask, "So the Arctic melted, and then what did you do?"

Alone among businesses, the fossil-fuel industry is allowed to dump its main waste, carbon dioxide, for free.

For those of us who worry more about working people than about windfall profits for oil companies, it may net out. A better question is: what does it do to our economy if we manage to overheat the earth? This summer's drought provides a small taste.