We
know it, but this comes from the Navy
U.S.
Navy researchers predict summer Arctic ice might disappear by 2016,
84 years ahead of schedule
27
November, 2013
Tucked
away on the third floor of the Naval Postgraduate School’s building
of Engineering and Applied Sciences, a small team of researchers is
leading an effort that will change the way the world thinks about the
world. Their project is the Regional Arctic System Model (RASM), and
it is arguably the most advanced – and accurate – Arctic climate
model in existence.
On
a recent, sunny winter day, U.S. Navy Lt. Dominic DiMaggio – a
master’s student in physical oceanography and meteorology and a
RASM team member – lays out the model’s virtues and complexities,
casually throwing around terms like “parameterization” and
“highly non-linear functions.”
Then,
almost 60 dizzying minutes later, he just as casually points to a
graph showing a RASM projection for melting Arctic sea ice, a
phenomenon that occurs every summer but has been accelerated by
climate change: By the summer of 2016, the Arctic Ocean could be
ice-free, opening the door to vast reserves of fossil fuel, and
eventually, freeing up a shipping lane between Europe and Asia.
NPS
Professor Wieslaw Maslowski, who leads the team of researchers behind
RASM, says 2016 is at “the lower bound” of the current range of
projections, while DiMaggio calls it “an aggressive interpretation”
of RASM. But most conventional climate models predict the Arctic
won’t have a sea ice-free summer until 2100. So why is the RASM
model so different?
Mainly,
it’s a matter of scope. Because most climate models are projecting
the global climate, there is not enough computing power to account
for what can often be key regional details.
One
example DiMaggio gives is the Bering Strait, a narrow strip of water
that is too small (51 miles wide) to be accurately accounted for in
the wider lens of global models, but which “is significant in its
impacts to the central Arctic.”
The
amount of detail that RASM is able to capture in the Arctic is at
least 10 times greater than a global model, and not only calculates
projections based on air, ocean and ice conditions (which are
standard in global models), but also includes inputs for land and
riverflow.
“We’re
modeling river runoff, the permafrost, the glaciers, even the
chemical and biological processes,” says DiMaggio. “The ocean
isn’t just the water, it’s the entire environment. And that’s
what we’re trying to capture.”
RASM’s
findings will help inform the Navy’s understanding of a region that
is home to over a thousand miles of U.S. coastline, and which is
changing faster than many expected, a reality charged with
geopolitical implications. The Navy predicts the potential for
extracting fossil fuels and minerals, as well as significantly
shorter shipping routes, will likely attract commercial interests.
The
stark image of an ice-free Arctic, meanwhile, might also impact the
climate change discussion, one that Maslowski hopes “will be a
critical argument against skeptics of global warming.”
RASM
has the potential to greatly alter current global climate models.
“We’re
hoping global modeling groups will use what we’ve learned to
improve their models,” Dimaggio says, “so the decision makers
have a better understanding of what’s actually happening.”
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