Melting sea ice means more rain in parts of Europe
British study shows ice retreat shifting jet stream south
Scientists have linked recent heavy rainfall in Britain and northwest Europe with the retreat of Arctic sea ice much farther north.
A new British study published in the journal Environmental Research letters finds that the loss of Arctic sea ice shifts the jet stream further south than normal, creating wetter summers in parts of Europe over the past five years.
“The study suggests that loss of sea ice not only has an effect on the environment and wildlife of the Arctic region but has far reaching consequences for people living in Europe and beyond,” said Dr. James Screen of the University of Exeter.
Jet streams are currents of strong winds found high in the atmosphere which steer weather systems and their rain.
The study compared weather patterns during low sea ice conditions — as seen in recent years — to weather patterns during high sea ice conditions typical of the late 1970s.
During a typical summer, the jet stream lies between Scotland and Iceland, while weather systems pass north of Britain.
But when the jet stream shifts south in summer, it brings unseasonable wet weather to Britain and northwest Europe, in some cases causing havoc for local agricultural and tourism.
According to the this study’s model, the effects of retreating sea ice are not limited to Europe; weather systems as far as North America could also be influenced.
Other studies have suggested that recent ocean warming of the North Atlantic could also be responsible for more summer rain in northwest Europe.
The annual average extent of Arctic sea ice is currently declining at about half a million square kilometres per decade – equivalent to about twice the area of the United Kingdom.
The results suggest that if sea ice loss continues as it has over recent decades, the risk of wet summers may increase.