We are altering the most basic forces of the planet's surface - the content of the sunlight, the temperature and aridity - and that brings out the most powerful questions about who is in charge. If you wanted to give a name to this theological problem, I think you could say that we are engaged in decreation.

Until it's understood to involve justice for those in poverty, a future for generations yet unborn, and a commitment to the rest of creation, it's unlikely we'll be able to overcome the status quo.

The polling data shows not an unbelievable level of concern [on climate issue] but a general awareness of this problem. And now I think it's up to all sorts of people who really care about these things to continue on this new ground to try and make this the central political issue it needs to be.

We're putting more carbon into the atmosphere than the atmosphere can absorb. And everybody told us when we started, coz we knew nothing when we started - we still don't know very much - but everybody told us 'this is crazy, you don't use a scientific data point, it's a number, people don't respond to numbers'.

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.

I don't know how to make people who absolutely have to be obsessed with paying a week's energy bills... obsessed with climate change... It's very hard.

For the first time in 150 years, the USDA reported there were more farms in America, not fewer. That has to make you happy.