Record-breaking
temperatures 'have robbed the Arctic of its winter'
Fort
Yukon has recorded Alaska’s coldest ever temperatures but this
winter temperatures have been much warmer than usual, leading to
dangerously thin ice
Suzanne Goldenberg
in Fort Yukon, Alaska
Tuesday 15 March
2016 17.48 GMT
This year’s
record-breaking temperatures have robbed the Arctic of its winter,
sending snowmobilers plunging through thin ice into freezing rivers
and forcing deliveries of snow to the starting line of Alaska’s
legendary Iditarod dogsledding race.
Last month’s high
temperatures – up to 16C (29F) above normal in some parts of the
Arctic – flummoxed scientists, and are redefining life in the
Arctic, especially for the indigenous people who live close to the
land.
In Fort Yukon, an
indigenous Gwich’in community eight miles inside the Arctic Circle,
the freakishly warm weather is forcing people off the rivers that are
their main transport corridors in the winter time.
“You can’t trust
the ice,” said Ed Alexander, Yukon Flats centre coordinator for the
University of Alaska at Fairbanks. “This is the warmest winter that
we have ever seen up here. We have had less snow. We have had real
thin ice. We have had an explosion of growth in the brush clogging up
trails and that kind of thing. It makes everything dangerous.”
Other communities
downriver lost a number of people this winter when their snowmobiles
fell through soft ice – and these were experienced hunters and
trappers, he said.
Alexander said he
and his wife had a narrow escape when they went out for a Sunday
drive on their snowmobile. “I noticed there was water all the way
across the river and I went to stop my snow machine and say: ‘Oh
maybe we should turn around and go back a different way’.”
By the time he
turned around to his wife, Alexander saw the back of the snowmobile
was already sinking into snow and soft ice. “We just took off and
there was as rooster tail of water coming out 30ft behind us,” he
said. “We made it back to shore but that will wake you up.”
Warm is a relative
term in Fort Yukon. The community nestled between the Yukon and
Porcupine rivers lays claim to the coldest – and hottest –
temperatures ever recorded in Alaska.
Temperatures at the
start of this week were well within the boundaries of what most of
the world would describe as very cold at –6C (20F), but that was
still up to 10C (18F) warmer than expected for this time of year.
“When I was
growing up it would warm up from 60 below to 20 below and we would be
walking around with T-shirts on,” said Craig Fleener, a Fort Yukon
native who advises the governor on climate change. “It’s all a
matter of perspective.”
This year, the
backwaters were already slushy by early March – so much so that
Fort Yukon had to start their dog sled races in the middle of town
rather than on the ice. The smell of sap was already coming off the
willows, and some plants were budding up, Alexander said.
Winter was almost
over – without ever getting cold enough to create the conditions
Arctic villagers rely on for their way of life.
In Fort Yukon, many
people depend on wood for heating in the winter months.
Come freeze-up, they
are out with heavy equipment on the river hauling timber. But without
a consistent run of extremely cold days – about two weeks of
temperatures approaching -51C (-60F) – the snow never gets hard
enough to pack into ramps or roads.
The ice over the
river never gets thick enough for heavy equipment, said Dacho
Alexander, a local magistrate and Ed’s brother.
“I normally like
to have an ice thickness of between 24 and 36 inches and generally up
here we have about 34 to 36 inches,” Dacho Alexander said. The ice
this year never made it beyond 20 inches, at the points where he drew
core samples.
“We really need
50-60 below in order for the ice to thicken up. Even if it is a week
or two weeks that gives us really good ice thickness. It’s not the
same to have two months of 10 below. The ice doesn’t get any
thicker.”
January and February
obliterated global temperature records – and nowhere more so than
in the Arctic which saw some locations 16C (29F) warmer than normal.
In late December,
temperatures at the North Pole rose to a balmy 0C – about 30C (54F)
above average.
“You can’t
overestimate how big the changes in warming we saw in January and
February in the Arctic,” James Overland, an Arctic and climate
change researcher at the National Oceanic and Atmospheric
Administration, told reporters covering the Arctic science summit in
Fairbanks.
“Not only have we
beaten the record, we have beaten it by an unbelievably large amount,
when you think of it in relation to how Arctic temperatures changed
in the past.”
The Arctic had
already been warming twice as fast as anywhere else over the last 30
years but scientists were still taken aback by the February records.
“We would never
have expected such a jump in one year,” Overland said. “It sends
us into a new temperature place that we have never seen before.”
The record
temperatures are already resounding across the Arctic and beyond –
melting the sea ice cover, thawing the permafrost and soil, and
shaking up the orderly patterns of the jet stream.
Researchers are
already beginning to connect such changes in the jet stream to
weather effects in mid-latitudes such as the unseasonable blasts of
cold Arctic air known as the polar vortex.
From where Ed
Alexander sees it, they had better get moving. “To put it in
context: I tell people to imagine what if Los Angeles was 60 degrees
warmer than it was supposed to be – because Fort Yukon is 60
degrees warmer than it’s supposed to be.
“People think the
changes up here are invisible … but if it only changes half as much
down there as it has changed up here you guys are in for a hell of a
lot of trouble.”
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