The Arctic is in a death spiral. How much longer
will it exist?
The region is unravelling faster than anyone could
once have predicted. But there may still be time to act
Gloria
Dickie
Tue 13 Oct
2020 10.00 BSTLast modified on Tue 13 Oct 2020 14.14 BST
At the end
of July, 40% of the 4,000-year-old Milne Ice Shelf, located on the
north-western edge of Ellesmere Island, calved into the sea. Canada’s last
fully intact ice shelf was no more.
On the
other side of the island, the most northerly in Canada, the St Patrick’s Bay
ice caps completely disappeared.
Two weeks
later, scientists concluded that the Greenland Ice Sheet may have already
passed the point of no return. Annual snowfall is no longer enough to replenish
the snow and ice loss during summer melting of the territory’s 234 glaciers.
Last year, the ice sheet lost a record amount of ice, equivalent to 1 million
metric tons every minute.
The Arctic
is unravelling. And it’s happening faster than anyone could have imagined just
a few decades ago. Northern Siberia and the Canadian Arctic are now warming
three times faster than the rest of the world. In the past decade, Arctic
temperatures have increased by nearly 1C. If greenhouse gas emissions stay on
the same trajectory, we can expect the north to have warmed by 4C year-round by
the middle of the century.
There is no
facet of Arctic life that remains untouched by the immensity of change here,
except perhaps the eternal dance between light and darkness. The Arctic as we
know it – a vast icy landscape where reindeer roam, polar bears feast, and
waters teem with cod and seals – will soon be frozen only in memory.
A new
Nature Climate Change study predicts that summer sea ice floating on the
surface of the Arctic Ocean could disappear entirely by 2035. Until relatively
recently, scientists didn’t think we would reach this point until 2050 at the
earliest. Reinforcing this finding, last month Arctic sea ice reached its
second-lowest extent in the 41-year satellite record.
“The latest
models are basically showing that no matter what emissions scenario we follow,
we’re going to lose summer [sea] ice cover before the middle of the century,”
says Julienne Stroeve, a senior research scientist at the US National Snow and
Ice Data Center. “Even if we keep warming to less than 2C, it’s still enough to
lose that summer sea ice in some years.”
At outposts
in the Canadian Arctic, permafrost is thawing 70 years sooner than predicted.
Roads are buckling. Houses are sinking. In Siberia, giant craters pockmark the
tundra as temperatures soar, hitting 100F (38C) in the town of Verkhoyansk in
July. This spring, one of the fuel tanks at a Russian power plant collapsed and
leaked 21,000 metric tons of diesel into nearby waterways, which attributed the
cause of the spill to subsiding permafrost.
This
thawing permafrost releases two potent greenhouse gases, carbon dioxide and
methane, into the atmosphere and exacerbates planetary warming.
The soaring
heat leads to raging wildfires, now common in hotter and drier parts of the
Arctic. In recent summers, infernos have torn across the tundra of Sweden,
Alaska, and Russia, destroying native vegetation.
This hurts
the millions of reindeer and caribou who eat mosses, lichens, and stubbly
grasses. Disastrous rain-on-snow events have also increased in frequency,
locking the ungulates’ preferred forage foods in ice; between 2013 and 2014, an
estimated 61,000 animals died on Russia’s Yamal peninsula due to mass
starvation during a rainy winter. Overall, the global population of reindeer
and caribou has declined by 56% in the last 20 years.
Such losses
have devastated the indigenous people whose culture and livelihoods are
interwoven with the plight of the reindeer and caribou. Inuit use all parts of
the caribou: sinew for thread, hide for clothing, antlers for tools, and flesh
for food. In Europe and Russia, the Sami people herd thousands of reindeer
across the tundra. Warmer winters have forced many of them to change how they
conduct their livelihoods, for example by providing supplemental feed for their
reindeer.
Yet some
find opportunities in the crisis. Melting ice has made the region’s abundant
mineral deposits and oil and gas reserves more accessible by ship. China is
heavily investing in the increasingly ice-free Northern Sea Route over the top
of Russia, which promises to cut shipping times between the Far East and Europe
by 10 to 15 days.
The
Northwest Passage through the Canadian Arctic Archipelago could soon yield
another shortcut. And in Greenland, vanishing ice is unearthing a wealth of
uranium, zinc, gold, iron and rare earth elements. In 2019, Donald Trump
claimed he was considering buying Greenland from Denmark. Never before has the
Arctic enjoyed such political relevance.
Tourism has
boomed, at least until the Covid shutdown, with throngs of wealthy visitors
drawn to this exotic frontier in hopes of capturing the perfect selfie under
the aurora borealis. Between 2006 and 2016, the impact from winter tourism
increased by over 600%. The city of Tromsø, Norway, dubbed the “Paris of the
north”, welcomed just 36,000 tourists in the winter of 2008-09. By 2016, that
number had soared to 194,000. Underlying such interest, however, is an unspoken
sentiment: that this might be the last chance people have to experience the
Arctic as it once was.
Stopping
climate change in the Arctic requires an enormous reduction in the emission of
fossil fuels, and the world has made scant progress despite obvious urgency.
Moreover, many greenhouse gases persist in our atmosphere for years. Even if we
were to cease all emissions tomorrow, it would take decades for those gases to
dissolve and for temperatures to stabilize (though some recent research
suggests the span could be shorter). In the interim, more ice, permafrost, and
animals would be lost.
“It’s got
to be both a reduction in emissions and carbon capture at this point,” explains
Stroeve. “We need to take out what we’ve already put in there.”
Other
strategies may help mitigate the damage to the ecosystem and its inhabitants.
The Yupik village of Newtok in northern Alaska, where thawing permafrost has
eroded the ground underfoot, will be relocated by 2023. Conservation groups are
pushing for the establishment of several marine conservation areas throughout
the High Arctic to protect struggling wildlife. In 2018, 10 parties signed an
agreement that would prohibit commercial fishing in the high seas of the
central Arctic Ocean for at least 16 years. And governments must weigh further
regulations on new shipping and extractive activities in the region.
The Arctic
of the past is already gone. Following our current climate trajectory, it will
be impossible to return to the conditions we saw just three decades ago. Yet
many experts believe there’s still time to act, to preserve what once was, if
the world comes together to prevent further harm and conserve what remains of
this unique and fragile ecosystem.
Gloria
Dickie
Tue 13 Oct
2020 10.00 BST
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