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Balmy Arctic links to global weather High temperatures and melting sea ice appear coupled with Arctic Vortex, ‘beast from the east’ and tropical thunderstorms
Alan Bailey Petroleum News
While not exactly sunbathing weather, the Arctic saw exceptional warmth in February, with temperatures 36 to 54 F above average over the North Pole, and 18 to 22 F above average over the Chukchi and Bering seas. According to the National Snow and Ice Data Center, a flow of warm air from the south resulted in open water developing in the Chukchi, to the north of the Bering Strait, and in largely ice-free water in the eastern Bering Sea.
But northern Europe saw a prolonged period of exceptionally cold weather, nicknamed “the beast from the east,” as frigid cold swept into the region from Siberia, resulting in heavy snow, transportation chaos and some cold-related deaths.
Linked events According to an article in The Conversation written by Peter Innes, a lecturer in meteorology in the University of Reading in the United Kingdom, these recent weather phenomena are all linked and tie back to a massive thunderstorm complex, “as large and strong as have ever been recorded,” that battered the western Pacific in late January.
According to Innes the thread tying all of these phenomena together is a wind system called the Polar Vortex, a westerly wind that normally circles the Arctic. Innes wrote that the thunderstorm system sent a series of pressure waves north through the atmosphere, ultimately disrupting the Polar Vortex and allowing cold Arctic air, normally trapped by the vortex, to spill south over Siberia.
The evolving weather pattern resulted in a high-pressure system over Scandinavia. The wind pattern circulating around this system resulted in frigid air flowing east from Siberia over northern Europe, while also causing relatively warm air to flow north from the Atlantic Ocean into the Arctic, Innes wrote.
The NSIDC also attributed the high temperatures at the North Pole to that northerly flow of air from the Atlantic, saying that low atmospheric pressure off the southeast coast of Greenland had contributed to the effect. The center also commented on low pressure just east of the Kamchatka Peninsula, in the Russian Far East, coupled with high pressure centered over Alaska and the Yukon during February. This pressure pattern sent a flow of warm air from the south, across the Bering Sea region, coupled with the movement of warm ocean water, which together help explain the loss of sea ice in the Bering and Chukchi seas and the exceptionally high temperatures in the region.
Climate change Innes expressed caution about interpreting the recent weather phenomenon as evidence of climate change, saying that one extreme weather event does not by itself say anything about long term climate trends. He characterized the phenomenon as an example of what is referred to as the “butterfly effect,” in which an apparently local weather event in one part of the world can have far reaching impacts elsewhere. That same package of thunderstorms in the western Pacific gave rise to the destructive Cyclone Gita that crossed the South Pacific, he wrote.
However, the NSIDC commented that this is the third winter in a row in which extreme heat waves have been recorded over the Arctic Ocean. The center pointed out that research conducted in the Norwegian Polar Institute has shown that the recent warm winters represent a trend towards the increased duration and intensity of winter warming in the central Arctic.
Scientists tend to view the Arctic sea ice extent as a means of assessing long term temperature trends. According to the NSIDC the ice extent at the end of February was at a record low for the time of year. And a plot of the extent for February since satellite observations began in the late 1970s shows a continuing trend of ice loss of 3.1 percent per decade.
The NSIDC also commented that this February a tanker made the first winter transit by a commercial vessel of the Northern Sea Route, the sea passage around northern Russia. The tanker has a strengthened hull, capable of handling sea ice 1.8 meters thick, the NSIDC said. A South Korean shipbuilder is constructing six ships with similar technology, the center said.
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