I think George W. Bush has a warm, engaging personality. But, you know, the presidency is more than just a popularity contest.

The conversation on global warming has been stalled because a shrinking group of denialists fly into a rage when it's mentioned.

I feel passionate about solving the climate crisis.

At some point, a false belief collides with physical reality.

I do genuinely believe that the political system is not linear. When it reaches a tipping point fashioned by a critical mass of opinion, the slow pace of change we're used to will no longer be the norm. I see a lot of signs every day that we're moving closer and closer to that tipping point.

If there is no cost to be paid for the indiscriminate dumping of pollution into the earth's atmosphere, then it should be a surprise to no one that today we will dump another 70 million tons of global warming pollution into the thin shell of atmosphere surrounding our planet. ... We have to [act] this year, not next year. Mother Nature does not do bailouts.

What we've often seen is that when we Americans say, look, we've got to reduce pollution, business - some businesses complain about it, but almost every time, it's turned out to be easier and cheaper and accomplished faster, and they've gained confidence, and then we go farther.