Climate change response
(Steve Connor/Herald, 24 December 2010) -- We may have to get used to the extreme weather after scientists established a link between cold snaps here and melting sea ice in the Arctic. They are now warning that long periods of freezing weather are likely to become more frequent. An analysis of the ice-free regions of the Arctic Ocean has found that the higher temperatures there caused by global warming, which have melted the sea ice in the summer months, have paradoxically increased the chances of colder winters in northern Europe. The findings are being assessed by climate scientists, who have been asked for advice on whether the past two cold winters are part of a wider pattern. Some believe the dramatic retreat of the Arctic sea ice over the past 30 years has begun to change the wind patterns over much of the northern hemisphere, causing cold, Arctic air to be funnelled over Ireland during winter. The study was carried out in 2009, before this year's harsh winter started to bite, and is all the more prescient because of its prediction that cold, snowy winters will be about three times more frequent. The researchers used computer models to assess the impact of the disappearing Arctic sea ice, particularly in the area of the Barents and Kara Seas north of Scandinavia and Russia, which have had unprecedented losses of sea ice during summer. Their models found that, as the ice cap over the ocean disappeared, this allowed the heat of the relatively warm seawater to escape into the much colder atmosphere above, creating an area of high pressure surrounded by clockwise-moving winds that sweep down from the polar region over Ireland.
Posted 28 December 2010; 1:17:51 PM. Permalink