Unprecedented warming has sent the Arctic into uncharted territory, says latest NOAA report, as its science faces potential hostility from the Trump administration.
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| Secretary of State John Kerry, center, visited Norway this year, witnessing the impacts of a melting Arctic. Credit: Getty Images |
The
ill winds of climate change are irrevocably reshaping the Arctic,
including massive declines in sea ice and snow and a record-late start
to sea ice formation this fall. Those were the sobering conclusions of
the 2016 Arctic Report Card released Tuesday.
The
report card is sponsored by the National Oceanic and Atmospheric
Administration (NOAA) and co-authored by more than 50 scientists from
Asia, North America and Europe. The data shows that the Arctic is
warming at double the rate of the global average temperature. Between
October 2015 and September 2016, temperatures over Arctic land areas
were 2.0 degrees Celsius above the 1981-2010 baseline, the warmest on
record going back to 1900.
The
report, released at the American Geophysical Union meeting in San
Francisco, clearly links the Arctic heatwave to a record-late start to
formation of sea ice this fall, and to record high and low seasonal snow
cover extent in the Northern Hemisphere. If the extreme warmth recorded
in the Arctic this fall persists for the next few years, it may signal a
completely new climate in the region, scientists said.
Jeremy
Mathis, director of NOAA's Arctic Research Program, said the report
highlights the clear and pronounced global warming signal in the Arctic
and its effects cascading throughout the environment, like the spread of
parasitic diseases in Arctic animals.
"We've
seen a year in 2016 like we've never seen before ... with clear
acceleration of many global warming signals. The Arctic was whispering
change. Now it's not whispering. It's speaking, it's shouting change,
and the changes are large," said co-author Donald Perovich, who studies
Arctic climate at Dartmouth College.
Sustained
observations of the Arctic is crucial to making science-based policy
decisions, he added, a goal threatened by the inclusion of numerous
climate deniers in President-elect Donald Trump's cabinet. This week,
Trump's transition team posted a new "Energy Independence" website
that repeats his previous intentions to open up vast areas for fossil
fuel development and to scrap existing climate action plans.
Arctic
ice doesn't care about politics, and what happens in the region now is
critically important to the U.S., said Rafe Pomerance, chair of Arctic
21 and a member of the Polar Research Board of the National Academies of Sciences, Engineering and Medicine.
"What
kind of Arctic do we want to have? It has to be one that maintains the
stability of the climate system," he said. "The melting of Greenland is
going to put an enormous hit on real estate values. The fate of
Greenland is the fate of Miami. It's in the U.S. national interest to
stop Greenland's ice sheet from melting. How are we going to bring it to
a halt?"
The
scientific report stands in stark contrast to the incoming
administration's apparent intention to foster more fossil fuel
development, he said.
"This
is a byproduct of the poison of denialism, a political issue that has
taken hold so deeply so that this is the kind of stuff that can be
contemplated," he said. "Evidence doesn't mean anything, science doesn't
seem to mean anything. They ought to take what's going on in the Arctic
really seriously. This is a crisis. The Arctic is unraveling."
The
report card underscores nearly a year of unusual conditions, said Lars
Kaleschke, an Arctic researcher at the University of Hamburg who was not
among the report's authors. Extremely warm air temperatures last
January and February led to the smallest maximum winter sea ice extent
on record, equaling the record set in 2015. And the return of extreme
warmth in November led to a short period of ice retreat at a time when
it's usually growing fast.
Kaleschke
said he's become concerned by reports that the incoming U.S.
administration may cut NASA's Earth observation budget, which includes
many programs critical to understanding Arctic global warming changes.
"That
would be a huge loss for the climate research community," he said.
Those programs are critical to efforts to understand rapid Arctic
changes. NASA's airborne IceBridge program, for example, helps confirm ice thickness measurements made by the European Space Agency's CryoSat program.
Kaleschke
said Trump appears to have a clear anti-science attitude that will
affect the world's ability to respond to climate change.
The
global warming signal was particularly evident in Greenland in 2016,
said Marco Tedesco, a climate researcher with Columbia University's
Lamont-Doherty Earth Observatory who was involved in the report.
"The
Greenland Ice Sheet continued to lose mass in 2016. The melt onset was
the second earliest and the melt season was 30 to 40 days longer than
average in the northeast, he said. Spring snow cover extent in Greenland
and other parts of the Arctic reached new record lows in spring and
there's new evidence that snow depth is also decreasing, which would be a
precursor to even earlier and faster melting."
Arctic
permafrost is also releasing more greenhouse gases in the winter than
plants can take up in the summer, making the Arctic a net source of
heat-trapping pollution, he added.
Snow
cover on land helps cool the entire Northern Hemisphere climate system,
insulates soil and regulates the water cycle through the seasons.
Highlighting the the recent changes in the Arctic is even more
important in light of the current political context, said University of
Sheffield geographer Edward Hanna, who co-authored the report's chapter
on air surface temperatures.
Air temperatures across the Arctic between January and March 2016
soared past previous record highs, with some locations reporting
anomalies of more than 8 degrees Celsius. In recent decades, there have
been more frequent surges of warm air from mid-latitudes far north into
the Arctic. That lends support to the emerging hypothesis that the
Arctic meltdown is changing the path of the jet stream, possibly leading
to more sustained extreme weather events in the Northern Hemisphere,
Hanna said.
The steady trend toward thinner, younger ice in the Arctic is also notable, suggesting the meltdown is irreversible.
"It's hard to see how the summer sea ice will survive," he concluded.
Links
The steady trend toward thinner, younger ice in the Arctic is also notable, suggesting the meltdown is irreversible.
"It's hard to see how the summer sea ice will survive," he concluded.
Links
- Obama Halts Arctic Oil Leases and Undoing It Won't Be Simple for Trump
- How Much Arctic Sea Ice Is Each of Us Melting? Quite a Bit, New Study Says
- Obama Halts Atlantic Drilling, but Keeps Arctic and Gulf Open for Business
- Wobbly Jet Stream Is Sending the Melting Arctic into 'Uncharted Territory'
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