https://www.washingtonpost.com/news/capital-weather-gang/wp/2017/02/01/beyond-the-extreme-scientists-marvel-at-increasingly-non-natural-arctic-warmth/
[images, video and links in on-line article]
‘Beyond the extreme’: Scientists marvel at ‘increasingly non-natural’
Arctic warmth
By Jason Samenow February 1 at 12:26 PM
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.
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.
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.”