How is it that, in the face of overwhelming scientific evidence, there are still some who would deny the dangers of climate change? Not surprisingly, the loudest voices are not scientific, and it is remarkable how many economists, lawyers, journalists and politicians set themselves up as experts on the science.

Enlightened self-interest from those involved in hydrocarbons should lead to the support of technologies enabling the clean use of hydrocarbons, such as carbon capture and storage, and not to the defence of deniers and cranks.

We will not overcome world poverty unless we manage climate change successfully. I've spent my life as a development economist, and it's crystal clear that we succeed or fail on winning the battle against world poverty and managing climate change together. If we fail on one, we fail on the other.

Those who say that climate change doesn't exist are being understood as the flat-earthers that they are, as the people who deny the link between smoking and cancer, as the people who denied the link between HIV and AIDS.

This [climate change] is potentially so dangerous that we have to act strongly. Do we want to play Russian roulette with two bullets or one?

It's very important that there should be cross-fertilisation between government and academia. Both parties can benefit from having a better understanding of how the other works.

What we are talking about is extended world war...People would move on a massive scale. Hundreds of millions, probably billions of people would have to move.