I
cannot find a reference to this. This came to me through Faeebook
New
findings coming out of
Canada
Hot
on the heels of last month seeing the lowest January sea ice extent
ever recorded in satellite history, Canadian scientists have
discovered that the Greenland ice sheet is now pumping vast amounts
of water into the oceans at the rate of around 8,000 tonnes every
second. 24 hours a day, 365 days a year.
Most
of the ice loss, representing a “very rapid change,” is meltwater
that can no longer sink back into glaciers and re-freeze. Instead, it
stays on the surface of the glaciers, forming large rivers that
eventually run off into the sea. This is happening because a thick
layer of ice that formed after the extreme 2012 melt season has
created an impermeable barrier to new meltwater. This new ice plug
means meltwater has nowhere else to go, apart from downhill towards
the Arctic Ocean.
As
the scientists said, “All the projections we made assumed the water
would keep percolating vertically. Now we can say that’s probably
not going to happen over large areas of the ice sheet.” This is
important because it means that previous climate change models and
projections may have underestimated just how much Greenland ice sheet
is contributing to sea-level rise today and in the future. Somewhat
ominously, one of the scientists added that "every time we have
a new result lately it turns out it's melting faster than we
thought."
Scientists "baffled"by ABRUPT climate change. Strange how some of us have been expeting something like this.
Arctic
sea ice growth stalls early, 'perplexing' scientists
Yereth
Rosen February 24, 2016
Sea
ice floats offshore, north of Barrow. Some climate scientists are
optimistic that humans can reduce the amount of carbon dioxide in the
atmosphere, allowing Arctic sea ice to rebound.
24
February, 2016
Normally
in the Arctic, the ocean water keeps freezing through the entire
winter, creating ice that reaches its maximum extent just before the
melt starts in the spring.
Not
so this year.
As
of Tuesday, sea ice had stopped growing for two weeks. Sea ice extent
-- the areas with at least 15 percent ice coverage -- hit a winter
maximum of 14.214 million square kilometers (5.488 million square
miles) on Feb. 9, and has stalled since, according to daily reports
from the National Snow and Ice Data Center in Colorado.
If
there is no more growth, the Feb. 9 total extent would be a double
record that would mean an unprecedented head start on the annual melt
season that runs until fall.
“If
this was the maximum in sea ice extent, it would be the earliest that
we’ve ever seen and it would also be the lowest maximum that we’ve
ever seen, by a long shot, actually,” said Mark Serreze, director
of the National Snow and Ice Data Center. “If this was the maximum,
that would be pretty big in terms of what is happening in the
Arctic.”
Up
to now, the lowest winter ice-extent maximum in the satellite record
dating back to 1979 was hit last year, when ice extent reached 14.54
million square kilometers (5.614 million square miles) on Feb. 25,
according to NSIDC records. The earliest seasonal winter maximum was
reached in 1996, when sea ice hit its peak extent on Feb. 24 of that
year, according to the center’s records. Normally, ice extent
reaches its maximum in early or mid-March; between 1981 and 2010, the
average maximum date was March 12.
Serreze
and his colleagues are not prepared to declare that the 2016 maximum
has now been reached and those new records set, however.
“I
think it’s too early to make any kind of call, although it is
certainly a very perplexing winter,” he said.
Extent
could bounce up if weather conditions change from what has been a
pattern of unusual Arctic warmth, he said. “There’s still a fair
bit of winter left in the Arctic,” he said.
But
even if ice starts growing again this winter, that would be only thin
ice that disappears quickly once the melt season starts, Serreze
said. “You don’t have any time left in the season to grow thick
ice,” he said.
The
extraordinarily low ice for February, which follows a record-low
January ice-extent average, has put extent in a “hole” for the
start of the 2016 melt season, he said.
“Where
will we end up in September? It depends so much on the summer weather
pattern,” he said. “But the odds are we’re going to have a very
low September.”
The
most notable lack of winter ice has been on the Atlantic side, near
Norway’s island of Svalbard, according to the center. Ice is also
low for this time of year in the Bering Sea and Pacific regions, with
direct impacts on Alaska, experts said.
“There
isn’t a lot of ice in Cook Inlet. There’s almost nothing in the
Bristol Bay region. And that’s remarkable,” said Tony Fischbach,
a U.S. Geological Survey wildlife biologist who compiles a daily
sea-ice report.
Residents
of Northwest Alaska, posting on the Alaska Native Tribal Health
Consortium’s Local Environmental Observer network, have provided
online evidence of warm conditions and sparse winter sea ice. Michael
Sloan of Nome sent photos and a description of a rainy Dec. 30, when
water puddled on what he said was an unusually small amount of intact
ice near the shore. Millie Hawley, president of the Native Village of
Kivalina, made similar observations in another Dec. 30 post, with a
photo of slush on the local lagoon.
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