New data reveals extraordinary global heating in
the Arctic
Temperatures in the Barents Sea region are ‘off the
scale’ and may affect extreme weather in the US and Europe
Damian
Carrington Environment editor
@dpcarrington
Wed 15 Jun
2022 10.00 BST
New data has revealed extraordinary rates of global
heating in the Arctic, up to seven times faster than the global average.
The heating
is occurring in the North Barents Sea, a region where fast rising temperatures
are suspected to trigger increases in extreme weather in North America, Europe
and Asia. The researchers said the heating in this region was an “early
warning” of what could happen across the rest of the Arctic.
The new
figures show annual average temperatures in the area are rising across the year
by up to 2.7C a decade, with particularly high rises in the months of autumn of
up to 4C a decade. This makes the North Barents Sea and its islands the fastest
warming place known on Earth.
Recent
years have seen temperatures far above average recorded in the Arctic, with
seasoned observers describing the situation as “crazy”, “weird”, and “simply
shocking”. Some climate scientists have warned the unprecedented events could
signal faster and more abrupt climate breakdown.
It was
already known that the climate crisis was driving heating across the Arctic
three times faster than the global average, but the new research shows the
situation is even more extreme in places.
Sea ice is
good at reflecting sunlight but is melting away. This allows the darker ocean
below to absorb more energy. Losing sea ice also means it no longer restricts
the ability of warmer sea waters to heat up the Arctic air. The more ice is
lost, the more heat accumulates, forming a feedback loop.
“We
expected to see strong warming, but not on the scale we found,” said Ketil
Isaksen, senior researched at the Norwegian Meteorological Institute and who
led the work. “We were all surprised. From what we know from all other
observation points on the globe, these are the highest warming rates we have
observed so far.”
“The
broader message is that the feedback of melting sea ice is even higher than
previously shown,” he said. “This is an early warning for what’s happening in
the rest of the Arctic if this melting continues, and what is most likely to
happen in the next decades.” The world’s scientists said in April that
immediate and deep cuts to carbon emissions and other greenhouse gases are
needed to tackle the climate emergency.
“This study
shows that even the best possible models have been underestimating the rate of
warming in the Barents Sea,” said Dr Ruth Mottram, climate scientist at the
Danish Meteorological Institute, and not part of the team. “We seem to be
seeing it shifting to a new regime, as it becomes less like the Arctic and more
like the North Atlantic. It’s really on the edge right now and it seems
unlikely that sea ice will persist in this region for much longer.”
The
research, published in the journal Scientific Reports, is based on data from
automatic weather stations on the islands of Svalbard and Franz Josef Land.
Until now, this had not been through the standard quality control process and
made public.
The result
was a high-quality set of surface air temperature measurements from 1981 to
2020. The researchers concluded: “The regional warming rate for the Northern
Barents Sea region is exceptional and corresponds to 2 to 2.5 times the Arctic
warming averages and 5 to 7 times the global warming averages.”
There was a
very strong correlation over time between air temperature, sea ice loss and
ocean temperature. Isaksen said the rapid temperature rise would have a very
big impact on ecosystems: “For instance, here in Oslo, we have a temperature
rise of 0.4C a decade and people really feel the disappearing snow conditions
during winter. But what’s happening in the far north is off the scale.”
Isaksen
said the new information on heating rates in the area would help research by
other scientists on how changes in the Arctic affect extreme weather in
populous areas at lower latitudes. There is evidence that the rapid heating
changes the jet stream winds that encircle the pole and influence extreme
weather.
“Sea ice
loss and warming in the Barents Sea in particular have been isolated in
previous work as being especially relevant to changes in winter-time
atmospheric circulation that are tied to extreme winter weather events,” said
Prof Michael Mann, from Pennsylvania State University, US. “If this mechanism
is valid, and there’s some debate over that, then this is yet another way
climate change could be increasing certain types of extreme weather events [and
which] isn’t well captured by current models.”

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