‘Beyond the extreme’: Scientists marvel at ‘increasingly non-natural’ Arctic warmth
Jason
Samenow
1
February, 2017
Arctic
temperature difference from normal during January. (WeatherBell.com)
The
Arctic is so warm and has been this warm for so long that
scientists are struggling to explain it and are in disbelief. The
climate of the Arctic is known to oscillate wildly, but scientists
say this warmth is so extreme that humans surely have their
hands in it and may well be changing how it operates.
Temperatures
are far warmer than ever observed in modern records, and sea ice
extent keeps setting record lows.
Unfortunately, influxes of "warm" air from both the Pacific/Atlantic Oceans this week will likely continue preventing #Arctic sea ice growth
2016
was the warmest year on record in the Arctic, and 2017 has picked up
right where it left off. “Arctic extreme (relative) warmth
continues,” Ryan
Maue, a meteorologist with WeatherBell Analytics, tweeted on
Wednesday,
referring to January’s temperatures.
Veteran
Arctic climate scientists are stunned.
“[A]fter
studying the Arctic and its climate for three and a half decades, I
have concluded that what has happened over the last year goes beyond
even the extreme,” wrote Mark Serreze, director of the National
Snow and Ice Data Center in Boulder, Colo., in
an essay for Earth magazine.
At
the North Pole, the mercury has rocketed to near the melting
point twice since November, and another huge flux of warmth is
projected by models next week. Their simulations predict some places
in the high Arctic will rise over 50 degrees above normal.
One
chart, in particular, is a jaw-dropping and emblematic display of the
intensity and duration of the Arctic warmth. It illustrates the
difference from normal in the number of “freezing degree days,” a
measure of the accumulated cold since September.
Averaged over the Arctic north of 80 degrees, this chart displays the difference from normal in the cumulative number of freezing degree days September to January. Freezing degree days accumulate according to the number of degrees Celsius below freezing. Minus-5 Celsius would represent five freezing degree days. (Nico Sun)
The
number of freezing degree days is far lower than any other period on
record. Eric Holthaus, a meteorologist and science writer who first
posted the chart to Twitter, remarked it illustrated a “stunning
lack of freezing power”
over the Arctic. “This is happening now,” he
added.
“Not in 50 or 100 years — now.”
The
chart was created by Nico Sun,
a citizen scientist, using temperature data from the high Arctic,
north of 80 degrees latitude, furnished
by the Danish Meteorological Institute.
Because
data is sparse in this region, David Titley, a professor of
meteorology at Penn State and Arctic climate expert, suggested “a
little” caution in interpreting the chart but said he considers it
“basically right” given other data. “This is another ‘smoking
gun’ pointing to rapid climate change,” he said.
Jason
Furtado, a professor of meteorology at the University of Oklahoma,
called the chart an “incredible” depiction of the Arctic warmth.
“While the magnitude of the Arctic warmth is extraordinary in and
of itself, the duration of the warmth has been astounding,” he
said.
Climate
scientists say there is no single cause for the remarkable warmth,
but posit it is due to natural variations in the Arctic climate
superimposed on a long-term warming trend resulting from human
activity.
Walter
Meier, a research scientist at NASA’s Goddard Space Flight Center
and an expert on Arctic sea ice, explained that the recent lack of
sea ice and warmer-than-normal ocean temperatures have “kept air
temperatures higher than normal, especially in the Barents and Kara
Seas” between Greenland and Siberia. “A series of storms tracking
from the south has led to repeated influx of warm air and ocean
waters into the region,” he said. Such an influx is predicted next
week.
Sun,
the chart’s creator, pointed to a recent lack of cold polar high
pressure systems over the Arctic, which block heat and moisture
transfer from mid-latitudes. “Now Atlantic and Pacific storms blow
right into the central Arctic and transform the area from a cold, dry
desert into a wet and stormy ocean,” he said.
But
it’s unclear and perhaps unlikely that this set of conditions,
which has essentially opened the floodgates for an onslaught of
warmth into the Arctic, represents a permanent state.
Zack
Labe, a PhD student at the University of California at Irvine who
is studying
Arctic sea ice and extreme weather,
said that while greenhouse gases will continue leading to a warmer
climate and less ice in the long run, the Arctic will probably
continue to experience significant year-to-year fluctuations.
“I
think we should be cautious, especially considering the resiliency of
sea ice, when discussing the warming trend,” Labe said. “It
remains uncertain the role natural variability may be having in
individual years such as this one.”
Yet
the human influence on climate in the Arctic may be redefining the
so-called natural variability, said Chip Knappenberger, a climate
scientist at the Cato Institute. “Natural variability is itself is
becoming increasingly ‘non-natural’ as it includes influences
which themselves are shaped by anthropogenic activities,” he said.
Such
a statement is notable coming from Knappenberger,who
some consider a climate change skeptic and
is unconvinced climate change is a serious problem.
What
happens next in the Arctic is anyone’s guess. But Penn State’s
Titley, who said we are “headed
into a new unknown” is
concerned: “Science is still trying to figure out the details. We
do know that 2017 will almost certainly start with the weakest,
thinnest, smallest arctic ice pack in recorded history. So we are one
step closer to living with an ice-free arctic in the summer, and
probably sooner than we think.”
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