Glaciers are melting in Artic Ocean
Arctic Ocean to have less ice, more water
by 2050s
by 2050s
The entire Arctic coastline and most of the Arctic Ocean will
experience an additional 60 days of open water each year
by the 2050s, according to a new study.
“We hear all the time about how sea ice extent in the Arctic
is going down,” said Katy Barnhart, who led the study while
at the University of Colorado Boulder’s Institute for Arctic
and Alpine Research (INSTAAR).
“That’s an important measurement if you are trying to
understand broad impacts of climate change in the Arctic,
but it doesn’t tell us about how the changes in the sea ice in
the Arctic are going to affect specific places,” said Barnhart.
Barnhart and her colleagues, including INSTAAR Fellow
Irina Overeem, set out to investigate the very local impacts
of open water expansion patterns in the Arctic.
Researchers used climate simulations from the National
Centre for Atmospheric Research-based Community Earth
System Model to see how the number of open water, or sea-
ice-free, days change from 1850 to 2100 in our planet’s
northernmost ocean.
They also wanted to understand when open water conditions
in specific locations would be completely different from pre-
industrial conditions.
Because most economic activity in the Arctic is along the
coastline, the team focused on four coastal locations that
demonstrated the range of sea ice change: Drew Point,
along Alaska’s North Slope; the Laptev Sea, along Siberia’s
northern coast; Perry Channel in the Canadian Arctic
Archipelago (part of the Northwest Passage route); and
Arctic Ocean regions east of Svalbard, Norway.
For example, at Drew Point, open water is already shifting
from preindustrial conditions. Once present about 50 days a
year on average (1900-2000), open water is now present
about 100 days a year.
By the 2070s, the modelling study concludes, there could be
close to 200 days a year with no sea ice at Drew Point,
which is likely to worsen coastal erosion.
“We wanted to highlight places that had interesting or
different stories with respect to the patterns of Arctic Ocean,
atmosphere, and sea ice motion – things like coastal erosion
or connections to potential sea routes,” said Barnhart, now a
postdoctoral fellow at the Annenberg Public Policy Centre of
the University of Pennsylvania.
“Since we don’t expect the impacts of Arctic sea ice loss to
be exactly the same in Alaska as in Greenland, we looked at
open water days to provide a more nuanced picture of sea
ice change at specific locations,” said Barnhart.
For the study, Barnhart and colleagues relied on climate
projections from 1850 to 2100 and analysed multiple runs or
“realisations” from a single climate model.
According to their analysis, the entire Arctic coastline and
most of the Arctic Ocean will experience an additional 60
days of open water each year by the 2050s, and many sites
will have more than 100 additional days.
The research was published in the journal Nature Climate
Change.
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