Warming hits ‘tipping point’

A vast expanse of western Sibera is undergoing an unprecedented thaw that could dramatically increase the rate of global warming, climate scientists warn today.

Researchers who have recently returned from the region found that an area of permafrost spanning a million square kilometres – the size of France and Germany combined – has started to melt for the first time since it formed 11,000 years ago at the end of the last ice age.