According to a new study, scientists have agreed for the first time that recent severe cold winter weather in the UK and US may have been influenced by the climate change in the Arctic.
The research, carried out by an international team of scientists including the University of Sheffield, has found that warming in the Arctic may be related to the jet stream’s position.
Warming in the Arctic in the winter can cause extreme cold weather, such as the winter of 2014/15, which saw record snowfall levels in New York.
Scientists previously had two schools of thought. One group believes that natural variability in the jet stream’s position has caused the recent severe cold winter weather seen in places such as the Eastern United States and the UK.
The other camp includes scientists who are finding possible connections between the warming of the Arctic, such as melting sea ice, warming air temperatures, and rising sea surface temperatures, and the emerging pattern of severe cold winter weather.
In the current study, researchers found evidence supporting both views.
The recent pattern of cold winters is primarily caused by natural changes to the jet stream’s position.
However, the warming of the Arctic appears to be exerting an influence on cold spells, but the location of these can vary from year to year.
Previous studies have shown that when the jet stream is wavy, there is more severe cold weather plunging south from the Arctic into the mid-latitudes.
But when the jet stream is flowing strongly from west to east and not very wavy, scientists tend to see more normal winter weather in countries within the mid-latitudes.
Researchers suggest that improving the ability to predict how climate change is affecting the jet stream will help improve the long-term prediction of winter weather in some of the most highly populated regions of the world.
This would be hugely beneficial for communities, businesses, and entire economies in the northern hemisphere.
The public could better prepare for severe winter weather and have access to extra crucial information that could help make live-saving and cost-saving decisions.
The study, Nonlinear response of mid-latitude weather to the changing Arctic, is published in the journal Nature Climate Change.
The research was partly sponsored by the International Arctic Science Committee (IASC) and the Climate and Cryosphere (CliC) project of the World Climate Research Programme (WCRP).
Citation: Overland JE, et al. (2016). Nonlinear response of mid-latitude weather to the changing Arctic. Nature Climate Change, 6: 992-999. DOI: 10.1038/nclimate3121.
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