Climate change causing intensely cold winters

Bob Kist of Mars, Pa. pushes his shopping cart of groceries to his car in the snowy store parking lot on Monday, Jan. 26, 2015 in Cranberry, Butler County, Pa. The Philadelphia-to-Boston corridor of more than 35 million people began shutting down and bundling up Monday against a potentially history-making storm that could unload a paralyzing 1 to 3 feet of snow. (AP Photo/Keith Srakocic)

When we think of climate change, we think of global warming and melting icebergs. But a new study is suggesting that climate change could also be the cause of incredibly cold winters on both sides of the Atlantic.
Warming in the Arctic is believed to be causing changes to the jet stream, which is a high-altitude corridor of fast-moving air. This is leading to severe spells of very cold weather.
It is now believed this phenomenon was responsible for the record amounts of snow which fell in New York during the winter of 2014, and the very cold winters felt by the UK in 2009 and 2010.
This latest research follows earlier studies which found when the jet stream follows an irregular route, more cold weather fronts come from the Artic, bringing freezing conditions which remain for weeks on end.
However, when the jet stream flows in a stronger, steadier manner from west to east, rather than in a wavy line, the winter weather in the UK and US is much milder.
Professor Edward Hanna, from the University of Sheffield, was the lead researcher on this study. He explained: “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.
“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.”
He explained that by making sure we better understand how climate change is having a major impact on the jet stream, we will be able to more accurately predict what sort of weather we will have each winter.
More accurate predictions could bring huge benefits for communities, businesses and the wider economy of areas within the UK and the US and other countries in the northern hemisphere.
Professor Hanna added: 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.”
He was part of an expert team made up of climate change scientists from across the world. Their research has been reported in the latest edition of the respected journal Nature Climate Change.
It could bring clarity following divisions among scientists who have been split on the cause of recent unnaturally cold winter seasons. One school of thought is that they are just part of a natural variability in the jet stream but the other belief is they are firmly connected with global warming as a whole.