Arctic sea-ice loss not the reason for cold winters
Research suggests a ‘minimal influence’ at best.
The dramatic loss of Arctic sea ice through climate change is not to blame for severe cold winter weather across Asia and North America, new research has shown.
When a British-Dutch team combined observations over the past 40 years with results from climate modelling, they found that reduced regional sea ice and cold winters often coincide because they are driven by the same, large-scale atmospheric circulation patterns.
However, the reduced sea ice only has a minimal influence on whether a harsh and severe winter will occur.
"The correlation between reduced sea ice and cold winters does not mean one is causing the other,” says mathematician and lead author Russell Blackport, from the University of Exeter, UK.
“We show that the real cause is changes in atmospheric circulation which moves warm air into the Arctic and cold air into the mid-latitudes."
The work, which involved colleagues from Exeter and researchers from the Royal Netherlands Meteorological Institute and the Energy and Sustainability Research Institute in Groningen, Netherlands, is described in a paper in the journal, Nature Climate Change.
The Arctic region has experienced warming temperatures through climate change over recent decades, leading to a large decline in sea-ice cover.
This decline means areas of open water increase, which in turn allows the ocean to lose more heat to the atmosphere in winter. This can potentially alter the weather and climate, even well outside the Arctic.
Recent studies have suggested reduced sea ice or Arctic warming has contributed to recent cold winters – leading to fears that such winters will become more frequent and severe.
But that’s not necessarily going to be the case.
"The are many reasons to be concerned about the dramatic loss of Arctic sea ice, but an increased risk of severe winters in North America and Asia is not one of them," says Exeter climate scientist James Screen.