Climate Change Shrinking Antarctic Snows
14
January, 2017
“When
I used to come to Antarctica in the 1990s, it never used to rain,”
said Rodolfo Sanchez, director of the Argentine Antarctic Institute
(IAA).
“Now
it rains regularly—instead of snowing,” he told AFP during an
Argentine government visit to King George Island, off the tip of the
western Antarctic peninsula.
Scientists
monitoring conditions at the base say the average temperature here
has increased by 2.5 degrees Celsius (4.5 degrees Fahrenheit) over
the past century.
“The
glacier used to reach all the way to the shore,” Sanchez says. “Now
there is a 500-meter (550-yard) wide beach.”
Dark
scars of rock are showing through what were once spotless sheets of
white snow on the glaciers’ flanks.
“Antarctica
is a thermometer that shows how the world is changing,” said
Adriana Gulisano, a physicist at Argentina’s National Antarctic
Directorate.
“There
is no place where climate change is more in evidence.”
Wildlife
signs
Local
wildlife also appears to reflect to the change.
Scientists
at the Carlini base say a pair of yellow-throated King penguins have
swum up to mate nearby for the past three years.
Although
the theory is not confirmed, they suspect another sign of climate
change. The species had previously been thought to be restricted to
warmer spots on the Falkland Islands and the Argentine mainland.
Technician
Luis Souza, 56, has divided his time since 1979 between Buenos Aires
and the Carlini base, where he has studied migrating birds:
cormorants, gulls and penguins.
More
crucially, scientists say melting ice is disrupting the breeding of
krill, a shrimp-like creature that serves as food for numerous
species.
“Less
ice means fewer krill for the whales, penguins and seals,” said
Sanchez. “The whole food chain is affected.”
The conventional wisdom
Since it never rains in Antarctica, does that mean it is technically adesert?
It scientifically is a desert.
Nestled around the South Pole, where the coldest temperature on Earth was recorded and which doesn't receive sunlight for months every year, it's sometimes hard to think of icy Antarctica as a desert. But it is the world's largest one because very little precipitation falls there — on average, it gets less than 2 inches (50 millimeters) a year, mostly as snow.Despite the low snowfall, vast glaciers cover 99 percent of Antarctica's surface. That's because the average temperature (minus 54 degrees Fahrenheit, or minus 48 degrees Celsius) slows down evaporation to a crawl. Over long periods of time, the snowfall accumulates at a rate faster than Antarctica's ablation, according to "Discovering Antarctica," a project of the U.K.'s Royal Geographical Society.
Parts of Antarctica are showing strong signs of warming up along with global climate change, however. Temperatures in the Antarctic Peninsula have increased by 4.5 degrees Fahrenheit (2.5 degrees Celsius) over the past 50 years — five times the rate of the rest of the planet. And scientists think that warm ocean waters could be melting Antarctica's glaciers as they flow under the floating tongues of ice.
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