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.

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

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.

The US will increasingly see the risks of being left behind, and ten years from now they would have to start worrying about being shut out of markets because their production is dirty.

Failing to curb the impact of climate change could damage the global economy on the scale of the Great Depression or the world wars by spawning environmental devastation that could cost 5 to 20 percent of the world's annual gross domestic product.

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.

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