A diet that relies heavily on meat production results in higher emissions than a typical vegetarian diet. Different individuals will make different choices. However, the debate about climate change should not be dumbed down to a single slogan, such as 'give up meat to save the planet.'

I think it's important that people think about what they are doing and that includes what they are eating. I am 61 now and attitudes towards drinking and driving have changed radically since I was a student. People change their notion of what is responsible. They will increasingly ask about the carbon content of their food.

If you look at all the serious scientists in the world, there is no big disagreement on the basics of this... it would be absolute lunacy to act as if climate change is not occurring.

I’ve never really had much of a career plan, and interesting opportunities kept cropping up.

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.

If coal is going to be used, the only response – because it is the dirtiest of all fuels – is that we have to learn how to do carbon capture and storage and we have to learn how to do it quickly on a commercial scale.

As an undergraduate, I did maths and physics. That doesn’t make me a scientist. So I try to read and understand and talk to scientists.

Do politicians understand just how difficult it could be, just how devastating rises of 4C, 5C or 6C could be? I think, not yet.

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.

You’d see more floods like you’ve seen in Mozambique in 2000, you’d see more droughts like you saw in Kenya in the late 1990s, there would be a serious threat to the water flow down the Nile on which 10 countries depend.