Shrinking heat shield of the planet
The reflective Arctic sea ice that serves as a heat shield for the
planet has melted to a new record low and government-backed scientists on Monday
said the Arctic may be largely ice-free as soon as 2020.
This month, up to 100,000 square miles of sea ice a day
disappeared, bringing overall shrinkage over the past three decades to 40 per
cent, according to data analysed over the weekend at the National Snow and Ice
Data Centre, located at the University of Colorado in Boulder.
The data show the area covered by sea ice shrank to 1.58 million
square miles, its lowest ebb in 32 years. That’s about 27,000 square miles less
than the previous low of 1.61 million square miles recorded Sept 18, 2007.
Another 150,000 square miles of sea ice could melt before the
middle of next month, when refreezing typically begins, NSIDC research scientist
Walt Meier said, during a conference call with colleagues at NASA.
The past six years have brought the six lowest levels of sea ice
since 1979, when measurements began. The climate scientists said the melting
will open shipping routes for energy companies hoping to claim untapped oil and
gas, while also worsening climate change worldwide.
“The Arctic is not like Las Vegas,” Mr. Meier said. “What happens
in the Arctic does not stay in the Arctic.” Arctic summers may be mostly
ice-free by 2020 to 2050, he said.
A previous Intergovernmental Panel on Climate Change report,
published in 2007, projected ice-free conditions around 2100. “The observations
show us going quicker than that,” Mr. Meier said.
NASA senior scientist Joey Comiso said some residual sea ice,
around 10 per cent, likely will remain. However, the data in recent years show
not only summertime declines, he noted, “but also quite significant declines in
the sea ice cover during winter”.
The dissolving of White Sea ice into darker open water means
reduced reflection. More sunlight is absorbed into oceans, raising water
temperatures. This ocean warming is seen by some as related to climate change,
affecting ocean currents, air currents and storm paths.
“The ocean warms when the ice cover is not there, so you get a lot
of warming within the Arctic Ocean that, from the ocean, can then feed back and
melt the ice,” Mr. Meier said.
“As far as the larger scale, when you’re heating up a region of
the world, compared to what it used to be, you’re changing the balance of the
climate system,” he said.
“Now, your air conditioner is losing coolant, so to speak. It’s
not as efficient as it used to be.”
Sea ice also is thinning, the scientists said. And this sea ice
capping the planet, as they described it, increasingly resembles slush.
The ice is more easily broken apart by storms, melted by summer
sunlight and reduced by warming waters. Climate-change modellers not involved in
the ice-observation project link the melting sea ice to global warming driven in
part by human use of fossil fuels.
The melting is working in favour of ships that haul drilling rigs
for extraction of new oil from the Arctic. U.S. Department of the Interior
officials is expected to approve exploratory drilling this year in the Chukchi
and other Arctic seas. — New York Times News Service
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