Drastic Arctic warm event stuns scientists, as record-breaking temperatures reach the North Pole

On Feb. 25, that weather station remained above freezing for about 24 hours, which is virtually unheard of during February, when there is no sunlight reaching the ground there.

Arctic sea ice in the Bering Sea and to the north of Greenland actually declined during February, a time when sea ice usually expands toward its seasonal maximum in early to mid-March.

Arctic scientists are poring over data coming in from the vast, normally frozen region, after the North Pole's version of a heat wave swept across the area for the past week. Not only was the region near the North Pole the warmest it has been during the month of February since at least the 1950s, but one of the northernmost land-based weather stations, known as Cape Morris Jesup, exceeded the freezing mark on an unprecedented nine separate days during the month. 

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Houses which people evacuated from are pictured after Saturday's avalanche which hit the Norwegian town of Longyearbyen, the biggest settlement on the Arctic archipelago of Svalbard, roughly midway between the North Pole and the northernmost tip of Europe, December 20, 2015. REUTERS/Tore Meek/NTB Scanpix ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. NORWAY OUT. NO COMMERCIAL OR EDITORIAL SALES IN NORWAY. NO COMMERCIAL SALES.
Snow is seen on the research centre, formerly a coal mining town, in Ny-Alesund, Svalbard, Norway October 13, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 04 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES����
Dawn at the scientific base of Ny-Alesund, Svalbard, Norway October 14, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 03 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES��
The old radio station for the mining town which is now a telegraph museum in Ny-Alesund Svalbard, Norway, October 13, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 06 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES����
Breinosa is seen from the research Zeppelin Observatory that is operated by operated by the Norwegian Polar Institute and Norwegian Institute for Air Research in Svalbard in Norway October 17, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna Filipova TPX IMAGES OF THE DAYPICTURE 01 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES
Snow is seen on the Ny-Alesund research centre, that was formerly a coal mining town October 19, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 08 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES��
Workers housing of Longyerbyean, Svalbard are seen covered in snow October 23, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna Filipova TPX IMAGES OF THE DAYPICTURE 05 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES
The northernmost non-military post office in the world in the Kings Bay research station in Ny-Alesund, Svalbard, Norway, October 18, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 10 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES����
An old locomotive train that was used for transporting coal is preserved as a monument at Ny-Alesund, in Svalbard, Norway, October 13, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna Filipova��PICTURE 12 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES
A scupted bust of Norwegian explorer Roald Amundsen is seen at the scientific base of Ny Alesund, in Norway, October 18, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 09 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES��
Warehouses and the old part of the Ny-Alesund, Norway settlement from the coal mining period which closed in 1963, are seen October 11, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 15 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES��
An overview of the residential and research settlement areas for scientists at the Kings Bay in Ny-Alesund, Svalbard, Norway, October 15, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 17 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES����
Snow covers Broggerdalen mountain near Ny-Alesund, Svalbard, Norway October 11, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 18 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES��
Radar dish and antennas systems are seen at the European Incoherent Scatter Scientific Association facility on Breinosa, Svalbard, in Norway, October 24, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna Filipova TPX IMAGES OF THE DAYPICTURE 13 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES
Low clouds are seen in the Kings Bay of Ny-Alesund, Svalbard, Norway, October 12, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 19 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES��
Dinghies and research vessels are pictured in the small harbour near Ny-Alesund on Spitsbergen, Norway October 15, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 16 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES��
The Coast Guard Cutter Healy breaks ice ahead of the Canadian Coast Guard Ship Louis S. St-Laurent (not seen) during an Arctic expedition in this August 31, 2009 handout photo. Government scientists will embark next week on a research expedition to monitor acidification trends in the Arctic Ocean, which is considered vulnerable to the effects of absorption of atmospheric carbon, the U.S. Geological Survey said August 10, 2011. The USGS scientists will journey for seven weeks on the Coast Guard cutter as close to the North Pole as possible to take water samples and test for chemical indicators, officials said. REUTERS/U.S. Coast Guard/Patrick Kelley/Handout (UNITED STATES - Tags: SCI TECH TRANSPORT ENVIRONMENT) FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. IT IS DISTRIBUTED, EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS
Reuters Environment Correspondent Gerard Wynn walks on some drift ice 500 miles (800 km) from the North Pole September 3, 2011. Wynn was with a team of Cambridge scientists trying to find out why Arctic sea ice is melting so fast. Arctic sea ice extent is expected to reach one of the lowest levels recorded by satellite since 1979, the head of the main monitoring station told Reuters. This means the five biggest summer melts will have all occurred in the past five years. Picture taken September 3, 2011. REUTERS/Stuart McDILL (ARCTIC SEA - Tags: MEDIA ENVIRONMENT SCIENCE TECHNOLOGY)
A member of a team of Cambridge scientists trying to find out why Arctic sea ice is melting so fast, walks on some drift ice 500 miles (800 km) from the North Pole September 3, 2011. The sea ice area retreats each summer and this year is closing on a record low in 2007. With one week of the melt season to go, it is now less than two-thirds of the area it covered in the early 1970s. The sea ice, distinct from ice sheets hundreds of metres thick over rock in Greenland, floats on the Arctic Ocean and wildlife including polar bears and walruses depend on it for survival. Picture taken September 3, 2011. REUTERS/Stuart McDILL (ARCTIC SEA - Tags: SCIENCE TECHNOLOGY ENVIRONMENT)
United Nations Secretary-General Ban Ki-moon (C) walks on the sea ice near an Arctic research ship during a tour to boost awareness of climate issues some 1,000 km (600 miles) from the North Pole, in this handout picture taken September 1, 2009. Standing on increasingly vulnerable Arctic sea ice, the Secretary-General made an impassioned plea for politicians to seal a global climate pact this year. Picture taken September 1, 2009. REUTERS/Mark Garten/UN Photo/Handout (ENVIRONMENT POLITICS IMAGES OF THE DAY) FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS
A small fishing boat sits on the shore of an Arctic island as the sun appears above the horizon for the first time following four months of polar darkness in one of Canada's northern most communities 1,921 Kms (1,200 miles) from the North Pole, January 18, 1999. The sun only appears on the horizon for about 10 or 20 minutes before setting again. The appearance of the sun has deep significance in Inuit life and signals the begining of new hunting season. REUTERS/Christopher Wilson (CANADA)
Reindeers graze near houses at an Arctic research base on the Norwegian island of Spitsbergen, 1,200 km (750 miles) from the North Pole, August 22, 2007. REUTERS/Alister Doyle (NORWAY)
The first snow of winter falls on traffic in the Norwegian Arctic research station of Ny Alesund, which calls itself the world's most northerly permanent settlement, August 20, 2007. Ny Alesund is about 1,200 km (746 miles) from the North Pole and was staging a seminar about climate change. In a contrast to the warnings about retreating ice and climate change, snow was falling in Ny Alesund on Monday, several weeks earlier than normal in a region still bathed by the midnight sun. About 30 to 130 people live in the fjord-side settlement, backed by snow-covered mountains. Picture taken August 20, 2007. REUTERS/Alister Doyle (NORWAY)
A man cycles through the Norwegian Arctic settlement of Ny Alesund August 20, 2007, as the first snows of winter arrive. Ny Alesund is about 1,200 km (746 miles) from the North Pole and was staging a seminar about climate change. In a contrast to the warnings about retreating ice and climate change, snow was falling in Ny Alesund on Monday, several weeks earlier than normal in a region still bathed by the midnight sun. About 30 to 130 people live in the fjord-side settlement, backed by snow-covered mountains. Picture taken August 20, 2007. REUTERS/Alister Doyle (NORWAY)
The Russian research vessel the Akademik Fyodorov with miniature submarines on board sails in the Arctic Ocean in this Reuters Television image taken from a television broadcast August 2, 2007. Two Russian submersibles started a dive into the Arctic Ocean on Thursday in a mission to symbolically claim the resource-rich region by planting a flag on the seabed under the North Pole, Russian media reported. REUTERS/Reuters Television (RUSSIA)
Barentsburg, a Russian coal mining town of 500 people sits up against a fjord in Norway's Svalbard archipelago about 1,000 kilometers (621 miles) from the North Pole, June 17, 2006. Fifteen years on from the collapse of communism, Russia is not about to abandon this Arctic outpost. To match feature LIFE ARCTIC RUSSIA. REUTERS/James Kilner (NORWAY)
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SEE ALSO: 'Beast from the East' brings snow to UK, mainland Europe along with frigid temperatures

Scientists interviewed for this story say that the Arctic warming event, technically known as a warm air intrusion, may be a common feature of the Arctic climate, as comparatively mild and moist air from the midlatitudes is transported north by storm systems. However, this event was not like the others, researchers said. 

In Greenland, monitoring stations registered unprecedented warmth at the top of the world's largest island. 

"I think it's fair to say that this event is unprecedented in our record — both in terms of the magnitude and (for Kap Morris Jesup at least) the duration," said Ruth Mottram, a climate scientist at the Danish Meteorological Institute, in a Twitter message, using the Danish spelling for Cape Morris Jessup. "The warm event at KMJ is not record breaking in terms of the highest ever recorded temperature in February, but that event in 2011 was very short-lived compared to what we have seen this year...," she said. "A prolonged period like this has definitely not been seen before."

She said some of the warmth in northern Greenland was likely due to downsloping winds known as Foehn winds, which can increase air temperatures. But that doesn't explain the warmth in the Arctic overall, when compared to average February conditions. "But when we look at the high Arctic overall, the temperature record since 1958 has never seen a warm spike of this magnitude in February," she said. "Having said that, the last few winters have seen similar events of very warm air coming in to the Arctic , though not nearly as large in magnitude," Mottram said. 

"I'm pretty surprised by quite how large the temperature anomaly is this year and how persistent." Noting cold temperatures on the west side of Greenland, Mottram emphasized that this was a weather event that was superimposed on top of rising average temperatures in the Arctic. The rising baseline makes it easier to attain all-time record highs, like a rising basketball floor making it more likely that a player will be able to dunk the ball in the net. 

A study published in 2017 found that these types of warming events have been increasing in frequency and duration during winter as the Arctic continues to warm at more than twice the rate of the rest of the globe. 

"What’s exactly driving these changes is not clear, but having storm tracks move further north (i.e. the North Atlantic storm track) may be tied to the northward retreat of the ice edge," said Julienne Stroeve, a senior research scientist at the National Snow and Ice Data Center in Boulder, Colorado, in an email. 

"Thus, while having temperatures exceed freezing during winter is not uncommon, but it may be becoming more common as the climate changes and the ice edge continues to retreat." 

Stroeve said that it's not just summer and fall sea ice showing steep declines, but that this is occurring year round now. "What it shows us too is that the winter sea ice is now also starting to respond as every winter now for the past 4 winters has been more extreme than the year before in terms of record low sea ice," she said.

The Arctic heat wave — though most wouldn't consider temperatures in the mid 30s to low 40s Fahrenheit to be "hot," this the Arctic in the dead of winter — has its roots in a weather system that pumped mild  and unusually moist air into the Arctic from the Atlantic, while another storm system did the same from the Pacific side of the Arctic. Winds blew from the southeast off the east coast of Greenland for the past week, driving this mild and moist air northward, toward the North Pole, where temperatures were about 45 degrees Fahrenheit higher than average for this time of year.

The warm air intrusion followed two other related and noteworthy weather events, a sudden warming of the stratosphere, known as a sudden stratospheric warming event, and a splitting of the polar vortex. These are both complex phenomena, but a sudden stratospheric warming event typically occurs when energy from the lower atmosphere travels upwards, and this can disrupt the area of low pressure and high westerly winds that comprise the polar vortex. 

One area of the vortex wound up in the Western U.S., while the other went to Eurasia, where it's helping to cause an Arctic outbreak in Europe known as the "Beast from the East." The net result of these events was that the ultra-cold air typically found in the Arctic during February drained out of the region, as if someone opened the Northern Hemisphere's freezer door and left it ajar. 

Zack Labe, a climate scientist at the University of California at Irvine, has a knack for creating compelling visuals of Arctic sea ice trends and air temperatures. His data corroborate this narrative, and this analogy, showing a sharp and persistent spike in air temperatures during February to the north of 80 degrees North Latitude.

"The duration of this warmth is remarkable and a common feature of the last several winters," Labe said in a Twitter message. He said that while warm air intrusions occur every winter, this one is unusual for occurring during February, lasting longer than a week, and for "the extent/magnitude of the moisture transport into the Arctic." 

"I think the takeaway is that the dramatic wintertime warming of the Arctic continues in addition to a long-term trend in decreasing sea ice. These effects, along with others, have significant physical, environmental, social, and political consequences for the Arctic and beyond," he said. 

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