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You won't find many climate deniers in the Arctic. From Sitka, Alaska to Svalbard, Norway, people are living through a period of extraordinarily rapid changes that are altering their ways of life.

Alaska just had its warmest December on record, with a staggering statewide average temperature anomaly of 15.7 degrees Fahrenheit above average for the month.

“To have an entire state that is a quarter the size, almost, of the Lower 48 [states], 15 degrees Fahrenheit above normal for an entire month is extraordinary,” said Brian Brettschneider, a climate scientist at the University of Alaska at Fairbanks, said in an interview.

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He said a huge swath of the state, about equal to the size of California, Washington, and Oregon combined, was close to 20 degrees Fahrenheit above average in December, thanks in large part to a powerhouse area of high pressure that sat near the Frontier State throughout the month.

Average temperature anomaly outlook for the next 7 days, showing unusually warm conditions across the Arctic, while Eurasia and the U.S. see colder than average conditions.Credit: Karsten Haustein

Alaska is set to experience yet another unusual warm-up in early to mid-February, as a gargantuan ridge of high pressure is projected to envelop the state from the North Pacific Ocean. The clockwise circulation around this high pressure area will cool off some parts of Alaska, but warm other areas – particularly in western Alaska – to well above average conditions.

The details of exactly how this weather pattern sets up will determine how drastically the temperatures will depart from normal for this time of year, Brettschneider said.

"Little changes in ridge axes make all the difference,” he said, referring to the orientation and precise location of such a weather system.

The lack of deep cold in a state whose people, natural systems, and economy depend on it has far-reaching consequences, experts say. For one thing, the buildup and maintenance of thick ice and snow cover is vital for establishing travel networks across a state that lacks roadways in most areas.

“It’s just so hard for people to grasp that in 90 plus percent of the state there is no highway network,” Brettschneider said. When people in rural communities need to travel, they usually have to snowmobile across a river, which needs to be reliably frozen in order to safely cross.

Norway. Svalbard Islands. Spitsbergen Island.Credit: UIG via Getty Images

Instead, ice has frozen over late, stayed thin, and been vulnerable to melting and refreezing due to a lack of snow cover. This has had tragic consequences, including travel-related deaths in the past two months.

The climate of Alaska, where minus-30 degree Fahrenheit days are typical in midwinter, helps maintain a deep layer of permanently frozen soil, known as permafrost. Right now, the permafrost is melting, and as it does so, it's releasing sizable quantities of global warming gases, including carbon dioxide and methane. This further speeds up global warming in what is known as a "positive feedback loop."

Bitterly cold days are key to permafrost maintenance and establishing what types of vegetation can be maintained in the state, Brettschneider said. As the state's average temperatures rise, different types of trees may start growing in some spots, as entire ecosystems shift northward with the intense cold.

Sea ice extent has been flirting with record low levels this winter across the Arctic.Credit: zack labe/nsidc

Permafrost is the reason why, in Alaska, students do not get to stay home from school for "snow days" like they do in the Lower 48 states. Instead, it's unusually warm weather that causes schools to be canceled in Alaska, because snowmelt and rain will freeze instantly upon contact with the permafrost. Snow-covered roads turn into skating rinks.

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In Fairbanks, rainfall during the winter used to be nearly unheard of, but in the past several years, including 2018, such weather has occurred.

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One contributor to the extraordinary warmth of December and parts of January was record low sea ice in the Bering and Chukchi Seas, off the southwest and northern coasts of Alaska.

“We had basically the latest ice over of the Chuckhi Sea in the satellite era," said Rick Thoman, a climatologist with the National Weather Service in Fairbanks, in an interview.

It was 65 degrees Fahrenheit, in Alaska, in the middle of January.

The absence of sea ice meant that air transported in from the southwest, west, and northwest, toward Alaska, was milder than it otherwise would have been, since sea ice cover tends to cool the air above it more than air above open ocean waters.

In Utqiaġvik, formerly known as Barrow, Alaska, which juts up against the Chuckchi Sea in far northern Alaska, temperatures were above average for a record 87 straight days, from Oct. 26, 2017 to Jan. 21, 2018, Thoman said.

With sea ice on a steep, long-term decline, this kind of climate feedback will happen more often.

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“The open water part of it shouldn’t be forgotten. What contribution did the open water play to the extraordinary warmth so far? It’s hard to say, but it’s not insignificant,” he said.

The warmth has affected every part of the state at various times this winter. For example, on Jan. 14, longstanding temperature records were obliterated in southeastern Alaska, while the rest of the state also experienced above-average temperatures.

Metlakatla, located in the Tongass National Forest of southeastern Alaska, the thermometer reached 65 degrees Fahrenheit, which is the warmest temperature ever recorded in the state during the month of January.

Think about for a moment: It was 65 degrees Fahrenheit, in Alaska, in the middle of January.

Not your grandparents' climate

This winter, like many other recent weird winters in Alaska, is reinforcing the message to Alaskans that the climate that their elders grew up with is not what they're living with now. Many are playing a game of catchup with the rapidly shifting environment.

“In rural Alaska, everyone knows what’s going on,” Thoman said. In urban Alaska, meaning places like Anchorage and Juneau, there's “more diversity of opinion,” Thoman said.

This winter is not just an oddity in locations such as Utqiaġvik and other parts of Alaska, but elsewhere around the tightly knit Arctic region, which is warming at about twice the rate of the rest of the globe.

Surface air temperature for the Arctic averaged above 80°N. Individual years from 1958-2016 are shown by the sequential blue/purple to yellow lines. 2018 is indicated by the red line and 2017 in yellow.Credit: zack labe

In Svalbard, Norway, which juts out into the Atlantic side of the Arctic, temperatures have averaged an astonishing 9.3 degrees Celsius, or about 16 degrees Fahrenheit, above average for the past 30 days, according to the Norwegian Meteorological Institute. Svalbard's sea ice area has hit the second-lowest level on record recently, as well, posing a challenge to native polar bears and other wildlife that depend on the sea ice for hunting prey.

Arctic sea ice extent across the vast Arctic Ocean is running at record low levels for this time of year, potentially headed for another record low annual peak. Studies have shown that the extent and speed of Arctic ice decline is unprecedented for at least the past 1,500 years, and that these trends are directly tied to increasing amounts of greenhouse gases in the air due to the burning of fossil fuels.

On shorter timescales, sea ice is significantly influenced by natural weather variability, which can push the ice further toward territory or hold it back from a milestone.

Weather patterns during the next several weeks may continue to hamper ice growth, perhaps keeping ice cover at record low levels, as unusually mild air repeatedly floods the Arctic from the Pacific side.

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