Arctic ice-melting affecting the weather in the northern hemisphere
The Guardian reports, 1st June 2015: The string of massive snowstorms and bone-chilling cold on the US east coast, as well as flooding in Britain and record temperatures in Europe, are linked to rapid ice loss in the Arctic, new research appears to confirm.
While the rapidly-thawing Arctic cannot be held responsible for specific weather events like the “snowmageddon” in 2009, Hurricane Sandy, or European heatwaves, researchers at Rutgers university said it appears to be a prime reason why the polar jet stream — a ribbon of winds that encircles the globe — gets ‘stuck’ with increasing frequency.
Western Europe and large parts of North America will experience more extreme weather because of “Arctic amplification” — the enhanced sensitivity of high latitudes to global warming, the team suggested in a paper published in the journal Philosophical Transactions of the Royal Society
Arctic is warming faster than elsewhere, triggering changes in the jet stream which will create more extreme weather in western Europe and North America, researchers say.
Photograph: Alamy
“We are seeing these extremes because the Arctic is warming faster than elsewhere. The whole lower atmosphere is heating up but the sea ice is the most observable. This is having this effect on the jet stream, making it extend further south and stay longer,” said co-author Jennifer Francis.
“The jet stream creates weather of all sorts and where you are in relation to it dictates whether it is hot or cold. When we have a ridge, or a big bulge, in the jet stream, it makes it extend further and stay longer. When that ridge is stronger it tends to be more persistent,” she said. The study builds on other research which shows how the changing Arctic may be affecting weather in mid latitudes. According to some, a slower jet stream takes a more meandering path as it encircles the northern hemisphere. Other studies have linked ice loss in the Barents and Kara seas to the north of Russia with extremely cold winters in central Asia.
According to the US Snow and Ice data centre, Arctic sea ice extent last month averaged 5.4 million square miles), the second lowest April ice extent in the satellite record. It is 313,000 sq m) below the 1981 to 2010 long-term average of 6m sq m) and 31,000 sq m) above the previous record low for the month observed in 2007.
Source: The Guardian, 1st June 2015. For the full text see www.theguardian.com/environment/2015/jun/01/rapid-arctic-ice-loss-linked-to-extreme-weather-changes-in-europe-and-us
