On our current path, all our great Gulf and Atlantic coast cities are at risk of meeting the same fate as New Orleans.

The entire western Siberian sub-Arctic region is melting, and it has all happened in the last three or four years.

Ideology trumps rationality. Most conservatives cannot abide the solution to global warming - strong government regulations and a government-led effort to accelerate clean-energy technologies in the market.

Since 1955 the oceans have absorbed roughly twenty times more heat than the atmosphere.

Would PBS go so far as to give air time to an even more extreme kind of disinformer, a Holocaust denier?

When people ask me what they should do, I reply, "Get informed, get outraged, and then get political."

On moral grounds, I think that if you believe a certain outcome is a very possible outcome, you have an obligation to tell people that. With global warming, the probability of a bad outcome if we stay on our current emission trends is incredibly high. If you know a bad outcome is likely to happen, what right do you have not to communicate that? You go into a doctor's office, what are they going to do - not tell you the diagnosis?