This confirms everything that we know about the Arctic ice from oobservations - that it is melting from below and this process does not stop with the ending of the melt season
Enough
Heat to Melt Interior Arctic Ocean Ice is Building Beneath the
Surface
Robert
Fanney
A
new study shows that the excess heat developed in newly ice free
zones is being transported beneath the central ice. This heat is
sequestered in a layer beneath the surface. But it contains enough
energy to keep large regions of the Beaufort Sea ice free during most
months if mixed, according to the new research.
‘Archived’ heat has reached deep into the Arctic interior, researchers say
By
Jim Shelton
August
29, 2018
Arctic
sea ice isn’t just threatened by the melting of ice around its
edges, a new study has found: Warmer water that originated hundreds
of miles away has penetrated deep into the interior of the Arctic.
That
“archived” heat, currently trapped below the surface, has the
potential to melt the region’s entire sea-ice pack if it reaches
the surface, researchers say.
“We
document a striking ocean warming in one of the main basins of the
interior Arctic Ocean, the Canadian Basin,” said lead
author Mary-Louise
Timmermans,
a professor of geology and geophysics at Yale University.
The
upper ocean in the Canadian Basin has seen a two-fold increase in
heat content over the past 30 years, the researchers said. They
traced the source to waters hundreds of miles to the south, where
reduced sea ice has left the surface ocean more exposed to summer
solar warming. In turn, Arctic winds are driving the warmer water
north, but below the surface waters.
“This
means the effects of sea-ice loss are not limited to the ice-free
regions themselves, but also lead to increased heat accumulation in
the interior of the Arctic Ocean that can have climate effects well
beyond the summer season,” Timmermans said. “Presently this heat
is trapped below the surface layer. Should it be mixed up to the
surface, there is enough heat to entirely melt the sea-ice pack that
covers this region for most of the year.”
The
co-authors of the study are John Toole and Richard Krishfield of the
Woods Hole Oceanographic Institution.
The
National Science Foundation Division of Polar Programs provided
support for the research.
Abstract
Arctic
Ocean measurements reveal a near doubling of ocean heat content
relative to the freezing temperature in the Beaufort Gyre halocline
over the past three decades (1987–2017). This warming is linked to
anomalous solar heating of surface waters in the northern Chukchi
Sea, a main entryway for halocline waters to join the interior
Beaufort Gyre. Summer solar heat absorption by the surface waters has
increased fivefold over the same time period, chiefly because of
reduced sea ice coverage. It is shown that the solar heating,
considered together with subduction rates of surface water in this
region, is sufficient to account for the observed halocline warming.
Heat absorption at the basin margins and its subsequent accumulation
in the ocean interior, therefore, have consequences for Beaufort Gyre
sea ice beyond the summer season.
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