When you go to China and the developing world, people understand more clearly the dangers that are coming at them because they're living closer to the margin. They don't have any of the false sense of invulnerability that Americans have. People from developing countries also feel that it's their right, if you're talking in terms of justice, to use fossil fuels like we did for a hundred years to get rich. It's hard for them to give up that vision.

Remember...this year has already seen more billion-dollar weather-related disasters than any year in US history. Last year was the warmest ever recorded on planet Earth. Arctic sea ice is near all-time record lows. Record floods from Pakistan to Queensland to the Mississippi basin; record drought from the steppes of Russia to the plains of Texas...This is what climate change looks like in its early stages.

Scientists had said, "If you keep burning coal and gas and oil, you will melt the Arctic." And then the Arctic melted just as they had predicted. Did Shell Oil look at the melt and say, "Huh, maybe we should go into the solar-panel business instead?" No, Shell Oil looked at that and said, "Oh, well, now that it's melted it will be easier to drill for more oil up there." That's enough to make you doubt about the big brain being a good adaptation.

It's our own throat that we are cutting in the end along with everyone else's. We need to be exercising precisely the kind of leadership that might allow us to nudge China and India, say, onto different energy trajectories, in order to improve our own chances of surviving this century.

If we had about 100 years, that sort of slow cultural conversion would be exactly the thing to do. But physics is calling the tune here. We've got to respond to a timetable that physics has set for us.

There is nothing that will discombobulate and degrade [more] the lives of people near the margin on this planet. You don't have to look much past New Orleans to see that. Who took the hit? Some of the poorest people in the U.S.

When you go to China and the developing world, people understand more clearly the dangers that are coming at them because they're living closer to the margin. They don't have any of the false sense of invulnerability that Americans have. People from developing countries also feel that it's their right, if you're talking in terms of justice, to use fossil fuels like we did for a hundred years to get rich. It's hard for them to give up that vision.