Rising temperatures shrink Arctic sea ice to second-lowest level on record
Sea ice
minimum has fallen below 4m sq km for the second time in 40 years as the
climate crisis rapidly transforms the region
Rising
temperatures in the Arctic shrank
the ice covering the polar ocean this year to its second-lowest extent in four
decades, scientists have announced, in yet another sign of how the climate
crisis is rapidly transforming the region.
Satellites
recorded this year’s sea ice minimum at 3.74m sq km on 15 September, only the
second time the ice has been measured below 4m sq km in 40 years of record
keeping, said researchers at the National Snow and Ice Data Center.
“It’s
fairly devastating that we’ve had such consistently low sea ice. But
unfortunately, it’s not surprising,” said Twila Moon, a glaciologist at the
research center in Boulder, Colorado.
The
record low of 3.41m sq km, reached in 2012 after a late-season cyclonic storm
broke up the remaining ice, is not much below what researchers see today.
This
year’s decline was especially fast between 31 August and 5 September, thanks to
pulses of warm air coming off a heatwave in Siberia, according to the NSIDC.
The rate of ice loss during those six days was faster than during any other
year on record. Another team of scientists found in July that the Siberian
heatwave would have been all but impossible without human-caused climate
change.
As the
Arctic sea ice vanishes, it leaves patches of dark water open. Those dark
waters absorb solar radiation rather than reflecting it back out of the
atmosphere, a process that amplifies warming and helps to explain why Arctic
temperatures have risen more than twice as fast as the rest of the world over
the last 30 years.
The loss
of sea ice also threatens Arctic wildlife, from polar bears and seals to
plankton and algae, said Tom Foreman, a polar wildlife expert and Arctic guide.
“The
numbers that we’re getting in terms of extent of sea ice decrease each year put
us pretty much on red alert in terms of the level of worry that we have, our
concern for the stability of this environment,” Foreman said.
The same
warming that is opening summertime Arctic waters is also eating away at the ice
sheets covering Arctic lands in Canada and Greenland. The faster those ice
sheets melt into surrounding ocean, the faster sea levels will rise worldwide.
Given
that a warmer Arctic could impact weather patterns worldwide, Moon said the
world should not wait for another new record sea ice low before taking action
to limit climate change.
“We
should work very hard to make differences in our emissions of polluting gases
so that we do not see so many records created in the future,” Moon said.
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