I think that once people understand the great risks that climate change poses, they will naturally want to choose products and services that cause little or no emissions of greenhouse gases, which means 'low-carbon consumption.' This will apply across the board, including electricity, heating, transport and food.

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.

I think that once people understand the great risks that climate change poses, they will naturally want to choose products and services that cause little or no emissions of greenhouse gases, which means 'low-carbon consumption.' This will apply across the board, including electricity, heating, transport and food.

The scientific evidence is now overwhelming: climate change presents very serious global risks, and it demands an urgent global response.

Looking back, I underestimated the risks. The planet and the atmosphere seem to be absorbing less carbon than we expected, and emissions are rising pretty strongly. Some of the effects are coming through more quickly than we thought then.

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.

The basic scientific conclusions on climate change are very robust and for good reason. The greenhouse effect is simple science: greenhouse gases trap heat, and humans are emitting ever more greenhouse gases.