I
am losing interest in these generalised articles that don't really
add to our understanding but are more about the media coming up to
speed.
The
Last of the Arctic's Old Sea Ice Is on the Verge of Vanishing
4
May, 2019
The
severe toll of climate change at the top of the world is becoming
clearer with each passing day. The latest sign comes courtesy of the
National Snow and Ice Data Center (NSIDC), which released its monthly
sea ice update on Thursday. It shows that just 1.2 percent of ice in
the Arctic Ocean is older than four years. Just 35 years ago, ice
that was four years old or older made up nearly a third of all Arctic
sea ice.
Old
sea ice is vital to holding Arctic icepack as a whole together. It
acts as an anchor for younger ice and a buffer against the storms
that pound the region. But as ocean and air temperatures have risen
in the Arctic, its extent has shrunk dramatically. As the new report
reminds us, old sea ice is now on life support. While the summer melt
season isn’t likely to deliver the final knockout punch, it will be
yet another blow to the region’s ice.
That
comes as the Arctic hit a new April low for sea ice extent, beating
out April 2016 for the ignominious title. The loss of old sea ice is
intimately tied to the disappearance of Arctic ice cover more
broadly. As it melts out, it’s been replaced by younger, thinner
ice that breaks up more easily when storms come through and melts
more readily in the warming waters.
If
this is the four-plus year old ice finally disappears, it will mark
the first time on record the Arctic has been without it. There’s a
chance it could come back as the winter refreeze happens depending on
what happens to ice in the 3-4 year age range over the course of the
summer. If some of this ice makes it through the summer, it would age
another year thus replenishing four-plus year old ice.
“The
majority of the 3+ year-old sea ice is located north of Greenland,”
Zack Labe, a PhD candidate at the University of California, Irvine
who studies the Arctic, told Earther in an email. “Recent IceBridge
and CryoSat-2 satellite observations indicate this area is highly
deformed sea ice and quite thick. It is very unlikely this ice will
melt during the summer.”
But
even the prospect of a slight bounce back of old ice this winter
doesn’t negate the trend of widespread ice loss in the Arctic nor
the fact that those losses will continue into the coming years. Mark
Serreze, NSIDC’s director, told Earther 5-10 years is a “more
reasonable” timeframe for old ice finally melt away. Research shows
the Arctic could see ice-free summers as early as the mid-2030s.
Other
parts of the region are undergoing similar dramatic changes. Recent
research has shown Greenland is losing six times more ice now than it
was in the 1980s while other findings show that the Canadian Arctic
hasn’t been as warm as it is now in at least 115,000 years. The
landscape is also destabilizing and unleashing a wild series of
landslides.
So
maybe pour one out for those places and the people that live there,
too.
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