Is Global Warming a bigger threat than terrorism?

Climate change poses a bigger threat to the planet than terrorism - so says the UK government's chief scientific adviser, Sir David King.

Droughts, forest-fires, heat waves, floods and storms have all hit the headlines in recent years.
The World Health Organisation's Europe Global Change and Health Programme has estimated that more than 25,000 people died in last year's European heat wave.

Most mainstream scientists believe that human activity - notably emissions of greenhouse gases - has contributed to a detectable increase in the average surface temperature of the planet.
British Prime Minister Tony Blair says addressing climate change is his key priority during the UK's chairing of the G8.

The Pentagon says climate change should be "elevated beyond a scientific debate to a national security concern."