Arctic temperature 'rising at twice global mean rate'

The Arctic is entering what is being described as "a new era" as temperatures rise and the ice covering the ocean becomes thinner, according to scientists taking part in an expedition run by the Norwegian Polar Institute.

Since the start of the year, the research vessel Lance has been drifting in the ice-pack to give scientists the chance to investigate how this region is changing.

The BBC's science editor David Shukman was given rare access to the project, and spoke to its director Jan-Gunnar Winther.