Researchers might have gotten to the bottom of why the US and Britain have had extremely cold winters recently.
Climate scientists from the University of Sheffield have agreed that climate change may be intensifying the effects of the jet stream, which in turn may cause extreme cold weather on both sides of the Atlantic.
The new study, published in the journal Nature Climate Change, found that the recent pattern of cold winters — such as in 2014-15 which saw record snowfall levels in New York — was mainly caused by changes to the positioning of jet streams, small meandering air currents that flow about 9-16 km (roughly 6 to 20 feet) above Earth’s surface.
Another factor the researchers hit upon is that the warming Arctic appears to be causing cold spells. The location of these spells can vary. In the past, these two ideas — moving jet streams and the warming Arctic — have divided climate scientists, but the team from Sheffield argue that both conditions play a role in what’s happening.
“We’ve always had years with wavy and not so wavy jet stream winds, but in the last one-to-two decades the warming Arctic could well have been amplifying the effects of the wavy patterns,” Professor Edward Hanna, one of the lead researchers involved with the study and a professor of geography at Sheffield, told Business Insider. “This may have contributed to some recent extreme cold winter spells along the eastern seaboard of the United States, in eastern Asia, and at times over the UK.”
When the jet stream is wavy, studies suggest there are more episodes of severe cold weather. On the other hand, when it’s flowing in a straight, strong line from west to east, we tend to see more normal winter weather conditions.
The team believe that their findings could be important for communities and businesses, as it will allow them to have a better idea of when extremely cold winters will strike, so to better prepare for them.
“Improving our ability to predict how climate change is affecting the jet stream will help to improve our long-term prediction of winter weather in some of the most highly populated regions of the world,” Hanna said. “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.”
Business Insider Emails & Alerts
Site highlights each day to your inbox.