2012年10月11日星期四

Arctic winds caused Britain's washout summers


Cool temperatures and endless rain could become the norm for British summers in future, according to experts from Sheffield University who studied the effects of climate change on wind patterns in the Arctic.

By analysing six years' worth of summer weather data, they found that changes in the direction of Arctic winds were linked to global warming and a rise in unseasonal weather.
Winds which normally blow from west to east have adopted a more wavy pattern, with stronger gusts blowing up from the Bering Strait, across the North Pole, and out to the Atlantic.
This process shifts warm air and sea ice further north, contributing to warmer temperatures and the record loss of summer sea ice recorded this year, scientists said.
It causes high pressure over Greenland, making for warmer and sunnier summers and increased melting of land ice, which leads to the increased likelihood of extreme weather in mid-latitude areas including Britain.
Dr Edward Hanna, one of the authors of the study published in the Geophysical Research Letters journal, said: “It's virtually impossible to predict the weather for any particular summer but we could have cooler, wetter summers on average in the UK because of this effect.
"That's not to say we won't get hot, dry summers but just that these might not be as frequent as you might expect from a straightforward global warming effect. There seems to have been a new regime in summer 2007 that has more or less stayed in place since."

more related:


没有评论:

发表评论