Researchers told Climate Central that the weather pattern driving the extreme cold into the U.S. — with a weaker polar vortex moving around the Arctic like a slowing spinning top, eventually falling over and blowing open the door to the Arctic freezer — fits with other recently observed instances of unusual fall and wintertime jet stream configurations.
Such weather patterns, which can feature relatively mild conditions in the Arctic at the same time dangerously cold conditions exist in vast parts of the lower 48, may be tied to the rapid warming and loss of sea ice in the Arctic due, in part, to manmade climate change.
Can extreme weather events like this weekend's historic outbreak of cold Arctic air across the U.S. be caused by the warming of the Arctic?
Though it seems counterintuitive – global warming bringing about extreme cold – the answer may be yes, according to scientists like Weather Underground's Dr. Jeff Masters and Dr. Jennifer Francis, a research professor at Rutgers University's Institute of Marine and Coastal Sciences.
The cause is believed to lie in the jet stream, the fast-flowing river of air high above the Earth that marks the boundary between cold, polar air to the North and warm tropical air to the South.
As the jet stream shifts position back and forth over North America throughout the year, it plays a major role in the weather patterns and temperatures we experience in the U.S. In recent years, the movement of the jet stream has changed significantly, bringing "weather whiplash" with strange, out-of-season weather events more frequently than in the recent past.
Francis has been a leading voice in recent years for research that points to rapid changes in the Arctic – including a dramatic decline over the past 30 years in Arctic sea ice extent, which exposes more of the Arctic Ocean to the sun's rays in the summer – as the likely culprit behind the jet stream's increasingly odd behavior.
source (archive.org)
These stories are about the record breaking cold of 2014
Is The Record Cold Arctic Outbreak Tied To Global Warming?
By Terrell Johnson
January 07, 2014
Can extreme weather events like this weekend's historic outbreak of cold Arctic air across the U.S. be caused by the warming of the Arctic?
Though it seems counterintuitive – global warming bringing about extreme cold – the answer may be yes, according to scientists like Weather Underground's Dr. Jeff Masters and Dr. Jennifer Francis, a research professor at Rutgers University's Institute of Marine and Coastal Sciences.
Now, new research from the Korea Polar Research Institute published in Nature Communications found a link between global warming and colder temperatures. Their research discovered that polar ice melts because warm water travels up the Gulf Stream from areas of the Atlantic Ocean, journeying towards regions of Europe such as Scandinavia. The melted ice leads to open water areas, releasing warmth into the air during the colder months. The result? A jet stream weakens, before moving south – and it carries cold air. Researchers of the study stated that if global warming continues to increase ocean temperature, then we are likely to experience colder winters.
Meteorologists said that no scientific research had been carried out into the cause of the heavy rain and floods that has blighted much of the country over Christmas and the New Year.
Winds of more than 60mph and huge waves battered the coastline from Cornwall to Scotland, with flooding affecting many parts of the UK, and motorists were tonight being warned that freezing temperatures would cause widespread ice in the morning.
The Met Office comments appeared to be at odds with that of David Cameron, who yesterday said at Prime Minister's Questions that climate change could well be linked to the recent storms.
Although winter persists, global climate change has made winters less harsh overall, say Schreck and other scientists. This phenomenon is evident from wintertime minimum temperature data, as shown in the graph below. During the period between 1910 and the 1980s, the land mass of the United States frequently experienced cold extremes during winter, according to NOAA’s National Centers for Environmental Information.
However, since 1990, few parts of the nation — typically no more than 10% of its area — have experienced extremely cold winters, a sign that bitter U.S. winters have become less widespread.
No comments:
Post a Comment