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

Time is short. We have at most a decade to sharply reverse course.

We created a way of raising standards of living that we can't possibly pass on to our children.

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

The great political tragedy of our time is that conservative leaders in America have chosen to use their superior messaging and political skills to thwart serious action on global warming.

As long as a handful of U.S. scientists, most receiving funds from the fossil fuel industry, get equal time with hundreds of the world's leading climate scientists, the public inevitably ends up with a misimpression about the state of our scientific understanding.

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