Without a movement pressing for change, there's little hope. We've got to work the political system to make this happen fast. The physics and chemistry are daunting. The resources on the other side are very large.

I just keep trying to explain what's going on with our planet - and now, to explain what's going on with our politics, which explains why we're not doing anything about the former.

In fact, corporations are the infants of our society - they know very little except how to grow (though they're very good at that), and they howl when you set limits. Socializing them is the work of politics. It's about time we took it up again.

That's why people are standing up again to fight the Keystone pipeline in Nebraska and South Dakota and Montana. Everyone is well aware of what this industry is about. It engages not only in those kind of practices, polluting people's water, but it has polluted our political life now for a quarter century.

I'm guessing the most efficient way would be to transfer an awful lot of technology, but also direct aid to deal with climate emergencies already underway. Hillary [Clinton] has already said $100 billion a year would be appropriate.

Permafrost in the soil [is melting], in the boreal and arctic areas in the world, and, probably even more alarming in the last six or eight months, the data on what is happening to the ice shelves in Greenland and the west Antarctic has begun to cause people to radically reassess the earlier conviction that those ice shelves were stable on a kind of century-long time scale.

There's no happy ending where we prevent climate change any more. Now the question is, is it going to be a miserable century or an impossible one, and what comes after that.