Baked Alaska: 49th state is having an insanely warm December
20
December, 2017
The
National Weather Service recently described Alaska’s weather so far
this month as “exceptionally mild.” That might be an
understatement.
Freakishly
warm conditions, compared to normal, are happening all over the
state. The snowpack and sea ice conditions are out of sorts. And
people don’t like it.
Fairbanks,
Anchorage and Juneau, as well as many remote towns, are having their
warmest December on record so far, according to Brian Brettschneider,
a climatologist based in Anchorage.
In
Fairbanks, temperatures have averaged an incredible 20 degrees above
normal. Setting aside Dec. 1, every day has been warmer than normal,
often much warmer. Most days have seen highs near 30 and lows near
10. That might sound cold, but the normal high is in the single
digits and the normal low around minus-10.
On
Dec. 8, Juneau soared to 54 degrees, tying its warmest temperature
ever recorded during the month. Three of its 10 highest December
temperatures on record came that week, the Juneau Empire reported.
“It was warmer in Juneau … than it was in Houston,” the
newspaper wrote. “That’s the Houston in Texas, not the one in
Southcentral Alaska.”
During
the middle of the month, Anchorage saw its temperature climb to at
least 45 degrees on four straight days, a record span for December.
It also tied its warmest winter day on record, Dec. 11, with an
average temperature of 41.5 degrees. The low temperature that day of
37 degrees matched the warmest of any winter month in history.
More-remote
Alaska outposts have also witnessed historically warm conditions. The
average temperature in Eagle, Alaska, near the Canadian border, is
running 23.5 degrees above normal so far, Brettschneider said. On
Dec. 14, Bettles, in north central Alaska, and Kotzebue, along the
west coast, tied monthly record highs of 38 and 37 degrees.
In
a place so brutally cold, one might think this mild weather is
welcome. No so, Brettschneider says. “People do not like the warm
temperatures,” he said in an email. “It makes things very icy
when the temperatures get above freezing. Since the ground is frozen
several inches thick, snow melting on the surface freezes to the
ground (or road). Because the sun is so low, it does not melt the ice
directly. Ice can hang around for weeks and even months.”
While
warm weather turns snow into a treacherous sheet of ice on the
ground, it melts ice on Alaska’s rivers or prevents it from
forming, taking away an important travel option. “Many of those
critical travel corridors are shut down,” Brettschneider said.
“Imagine shutting down the Interstate highway connecting Key West
from Miami.”
Bering Sea ice extent from the high resolution multi-sensor@NSIDC MASIE database as of Dec 16th is 2nd lowest (since 2006). Analysis from @NWSAlaska. For longer context, 2017 also 2nd lowest in the lower-res passive mircowave (since 1978). #Arctic #akwx @Climatologist49 @ZLabe
In
addition, sea ice, important for protecting vulnerable coastlines
from wave action during storms, is near-record low levels in the
Bering Sea, Brettschneider noted.
The
warm weather pattern over the state dates back months. In Utqiaġvik,
Alaska, previously known as Barrow, 74 of the last 79 days have been
warmer than normal, going back to Oct. 1.
For
the state as a whole, warmer-than-normal days have outnumbered the
cold 3 to 1 since April.
Weather
forecasting models suggest the remainder of December will also be
abnormally warm. Brettschneider tweeted that it is a “near lock”
that Fairbanks will have its warmest December on record.
In
a bit of irony, the forecast is for colder weather on Hawaii’s Big
Island peaks, where one to two feet of snow is predicted, than in
Anchorage over the next few days.
Alaska’s
pervasive and persistent warmth is the result of a bulging ridge in
the jet stream that has allowed mild air from the Pacific Ocean to
flood the state. This is the same jet stream pattern bringing
unusually warm, dry and fire-inducing weather to California and, on
the flip side, cold to the eastern United States.
High
altitude weather pattern forecast by European model shows massive
upper level ridge over Alaska — the same pattern which has brought
the state warm temperatures for much of this month. (WeatherBell.com)
But
the exceptionally warm weather in Alaska is not a mere reflection of
the current weather pattern but part and parcel of the state’s
long-term temperature trend. Alaska’s average temperature reached
its highest point since records began in 1930.
Extremely
mild this month in Alaska, but that's hardly new. The 60-month
running average temperature (through November), which smooths out
individual El Niño & La Niña years, is higher now than any time
in the past 88 years. #akwx #Arctic
Extremely mild this month in Alaska, but that's hardly new. The 60-month running average temperature (through November), which smooths out individual El Niño & La Niña years, is higher now than any time in the past 88 years. #akwx #Arctic@Climatologist49
Alaska
is responding to climate change, warming the Northern Hemisphere’s
high-latitude regions more than anywhere. Just last week, NOAA’s
latest report on the Arctic said that it “shows no sign of
returning to reliably frozen region of recent past decades.”
In his blog post A new green land, Alaskan journalist Craig Medred lamented the great thaw occurring over his state. “For Alaskans who love real winters,” he wrote, “there are only two words for what it has brought to the start of winter … ‘This sucks.’ ”
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