Melting Arctic link to severe winters
27 February 2012 Last updated at 23:39 GMT
The severe winters experienced in the UK and other areas of Europe, North America and China in the past few years could be linked to the melting of Arctic sea ice.
Research from a team of US and Chinese scientists suggests the strongest link yet between the volume of ice, which has shrunk by a third in the past 30 years, and changing weather patterns across the northern hemisphere.
David Shukman reports.