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.

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

If Americans in 2100 came to see 12 meters sea-level rise as inevitable by 2200, who can even begin to fathom how the nation would respond?

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

The best thing about improvements in health care is that all the climate-change deniers are now going to live long enough to see how wrong they were.

Do believe that if we fail to act in time, it will be the single biggest regret any of us has at the end of our lives.

Replacing half of the U.S. ground-transport fuels with hydrogen from wind power by 2050, for example, might require 1,400 gigawatts of advanced wind turbines or more... replacing those fuels with electricity might require less than 400 GW.