Extract from The Guardian
Fort Yukon has recorded Alaska’s coldest ever
temperatures but this winter temperatures have been much warmer than
usual, leading to dangerously thin ice
A lack of snow in south central Alaska forced race
organisers to move the Iditarod dog sled race north. Photograph:
Loren Holmes/AP
Suzanne
Goldenberg in Fort Yukon, Alaska
Wednesday 16 March 2016 04.48 AEDT
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
(61F) 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.
Persistent above-freezing temperatures have melted
much of the local snow in Anchorage, leading to snow being sent in by
train for the start of the famous Iditarod dog sled race. Photograph:
Rachel D'Oro/AP
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 (50F) 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 (61F)
warmer than normal.
In late December, temperatures at the North Pole
rose to a balmy 0C – about 30c (86F) 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 degree 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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