What we have lived through, the 20th century, has been like a great party. Adults now have had the best time humanity has ever had. Now the party is over and the Earth is reckoning up.

I'm not religious, but I put it that way because I feel so strongly. It's the one thing you do not ever do. You've got to have standards.

We thought we knew 20 years ago. That led to some alarmist books – mine included – because it looked clear-cut, but it hasn’t happened. The climate is doing its usual tricks. There’s nothing much really happening yet. We were supposed to be halfway toward a frying world now. The world has not warmed up very much since the millennium. Twelve years is a reasonable time. The temperature has stayed almost constant, whereas it should have been rising - carbon dioxide is rising, no question about that.

Climate change now represents so urgent a threat to mankind that the only way to deal with it is by suspending democracy.

I have heard that the Saudi Arabians are paying Greenpeace to campaign against Nuclear Power. It wouldn't surprise me at all.

By 2040, the Sahara will be moving into Europe and Berlin will be as hot as Baghdad. Atlanta will end up a kudzu jungle. Phoenix will become uninhabitable, as will parts of Beijing (desert), Miami (rising seas) and London (floods). Food shortages will drive millions of people north, raising political tensions.

The tropical rain forests are a telling example. Once cut down, they rarely recover. Rainfall drops, deserts spread, the climate warms.