Record-low 2016 Antarctic sea ice due to ‘perfect storm’ of tropical, frigid conditions

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While winter sea ice in a Arctic is disappearing so dramatically that ships can now navigate those waters though any icebreaker escort, a stage in a Southern Hemisphere is unequivocally different. Sea ice area around Antarctica has indeed augmenting somewhat in winter — that is, until final year.

After augmenting somewhat in new decades, a sea ice border around Antarctica plummeted in 2016. Image credit: Malte Stuecker/University of Washington

A thespian dump in Antarctic sea ice roughly a year ago, during a Southern Hemisphere spring, brought a limit area down to a lowest turn in 40 years of record keeping. Ocean temperatures were also scarcely warm. This exceptional, remarkable nosedive in Antarctica differs from a long-term decrease in a Northern Hemisphere. A new University of Washington investigate shows that a miss of Antarctic sea ice in 2016 was in partial due to a singular one-two punch from windy conditions both in a pleasant Pacific Ocean and around a South Pole.

The study was published Aug. 24 in Geophysical Research Letters.

“This multiple of factors, all these things entrance together in a singular year, was fundamentally a ‘perfect storm,’ for Antarctic sea ice,” pronounced analogous author Malte Stuecker, a UW postdoctoral researcher in windy sciences. “While we design a delayed decrease in a destiny from tellurian warming, we don’t design such a fast decrease in a singular year to start unequivocally often.”

The percent of sea aspect lonesome with sea ice in 2016 was reduce than common (brown) over many tools of a Southern Ocean. The black line shows a corner of a segment with during slightest 15 percent ice cover. Image credit: Malte Stuecker/University of Washington

The area of sea ice around Antarctica during a rise in late 2016 was 2 million block kilometers (about 800,000 block miles) reduction than a normal from a satellite record. Statistically, this is 3 customary deviations divided from a normal — an eventuality that would be approaching to start incidentally usually once each 300 years.

The record low was not likely by meridian scientists, so UW researchers looked during a bigger design in sea and windy information to explain since it happened.

The prior year, 2015-16, had a unequivocally clever El Niño in a pleasant Pacific Ocean. Nicknamed a “Godzilla El Nino,” a eventuality was identical to other beast El Niños in 1982-83 and 1997-98. Unlike a 1997-98 event, however, it was usually followed by a comparatively diseased La Niña in 2016.

Far divided from a tropics, a pleasant El Niño settlement creates a array of high- and low-pressure zones that means scarcely comfortable sea temperatures in Antarctica’s eastern Ross, Amundsen and Bellingshausen seas. But in 2016, when no clever La Niña materialized, researchers found that these scarcely comfortable aspect pools lingered longer than common and influenced freeze-up of seawater a following season.

“I’ve spent many years operative on pleasant meridian and El Niño, and it amazes me to see a inclusive impacts,” Stuecker said.

Meanwhile, observations uncover that a winds encircling Antarctica were scarcely diseased in 2016, definition they did not pull sea ice divided from a Antarctic seashore to make room for a arrangement of new ice. This influenced ice arrangement around most of a Southern Ocean.

“This was a unequivocally singular multiple of events, something that we have never seen before in a observations,” Stuecker said.

The researchers analyzed 13,000 years of meridian indication simulations to investigate how these singular conditions would impact a sea ice. Taken together, a El Niño settlement and Southern Ocean winds explain about two-thirds of a 2016 decline. The rest might be due to unusually vast storms, that a prior paper suggested had damaged adult ice floes.

Scientists envision Antarctica’s sea will be one of the last places on Earth to knowledge tellurian warming. Eventually a Southern Ocean’s aspect will start to warm, however, and afterwards sea ice there will start a some-more long-term decline.

“Our best guess of a Antarctic sea ice turnaround indicate is someday in a subsequent decade, though with high doubt since a meridian vigilance is tiny compared to a vast variations that can start from one year to a next,” pronounced co-author Cecilia Bitz, a UW highbrow of windy sciences.

Stuecker remarkable that this form of big, singular continue eventuality is useful to assistance know a production behind sea ice formation, and to learn how best to explain a observations.

“For bargain a meridian complement we contingency mix a atmosphere, sea and ice, though we contingency concentration on some-more than a specific region,” Stuecker said. “If we wish to know sea ice in Antarctica, we can't usually wizz in locally — we unequivocally have to take a tellurian perspective.”

The other co-author is Kyle Armour, a UW partner highbrow of windy sciences and oceanography. The investigate was saved by a National Science Foundation and a National Oceanographic and Atmospheric Administration’s Climate and Global Change Postdoctoral Fellowship Program, administered by a University Corporation for Atmospheric Research’s Cooperative Programs for a Advancement of Earth System Science.

Source: University of Washington

Comment this news or article

While winter sea ice in a Arctic is disappearing so dramatically that ships can now navigate those waters though any icebreaker escort, a stage in a Southern Hemisphere is unequivocally different. Sea ice area around Antarctica has indeed augmenting somewhat in winter — that is, until final year.

After augmenting somewhat in new decades, a sea ice border around Antarctica plummeted in 2016. Image credit: Malte Stuecker/University of Washington

A thespian dump in Antarctic sea ice roughly a year ago, during a Southern Hemisphere spring, brought a limit area down to a lowest turn in 40 years of record keeping. Ocean temperatures were also scarcely warm. This exceptional, remarkable nosedive in Antarctica differs from a long-term decrease in a Northern Hemisphere. A new University of Washington investigate shows that a miss of Antarctic sea ice in 2016 was in partial due to a singular one-two punch from windy conditions both in a pleasant Pacific Ocean and around a South Pole.

The study was published Aug. 24 in Geophysical Research Letters.

“This multiple of factors, all these things entrance together in a singular year, was fundamentally a ‘perfect storm,’ for Antarctic sea ice,” pronounced analogous author Malte Stuecker, a UW postdoctoral researcher in windy sciences. “While we design a delayed decrease in a destiny from tellurian warming, we don’t design such a fast decrease in a singular year to start unequivocally often.”

The percent of sea aspect lonesome with sea ice in 2016 was reduce than common (brown) over many tools of a Southern Ocean. The black line shows a corner of a segment with during slightest 15 percent ice cover. Image credit: Malte Stuecker/University of Washington

The area of sea ice around Antarctica during a rise in late 2016 was 2 million block kilometers (about 800,000 block miles) reduction than a normal from a satellite record. Statistically, this is 3 customary deviations divided from a normal — an eventuality that would be approaching to start incidentally usually once each 300 years.

The record low was not likely by meridian scientists, so UW researchers looked during a bigger design in sea and windy information to explain since it happened.

The prior year, 2015-16, had a unequivocally clever El Niño in a pleasant Pacific Ocean. Nicknamed a “Godzilla El Nino,” a eventuality was identical to other beast El Niños in 1982-83 and 1997-98. Unlike a 1997-98 event, however, it was usually followed by a comparatively diseased La Niña in 2016.

Far divided from a tropics, a pleasant El Niño settlement creates a array of high- and low-pressure zones that means scarcely comfortable sea temperatures in Antarctica’s eastern Ross, Amundsen and Bellingshausen seas. But in 2016, when no clever La Niña materialized, researchers found that these scarcely comfortable aspect pools lingered longer than common and influenced freeze-up of seawater a following season.

“I’ve spent many years operative on pleasant meridian and El Niño, and it amazes me to see a inclusive impacts,” Stuecker said.

Meanwhile, observations uncover that a winds encircling Antarctica were scarcely diseased in 2016, definition they did not pull sea ice divided from a Antarctic seashore to make room for a arrangement of new ice. This influenced ice arrangement around most of a Southern Ocean.

“This was a unequivocally singular multiple of events, something that we have never seen before in a observations,” Stuecker said.

The researchers analyzed 13,000 years of meridian indication simulations to investigate how these singular conditions would impact a sea ice. Taken together, a El Niño settlement and Southern Ocean winds explain about two-thirds of a 2016 decline. The rest might be due to unusually vast storms, that a prior paper suggested had damaged adult ice floes.

Scientists envision Antarctica’s sea will be one of the last places on Earth to knowledge tellurian warming. Eventually a Southern Ocean’s aspect will start to warm, however, and afterwards sea ice there will start a some-more long-term decline.

“Our best guess of a Antarctic sea ice turnaround indicate is someday in a subsequent decade, though with high doubt since a meridian vigilance is tiny compared to a vast variations that can start from one year to a next,” pronounced co-author Cecilia Bitz, a UW highbrow of windy sciences.

Stuecker remarkable that this form of big, singular continue eventuality is useful to assistance know a production behind sea ice formation, and to learn how best to explain a observations.

“For bargain a meridian complement we contingency mix a atmosphere, sea and ice, though we contingency concentration on some-more than a specific region,” Stuecker said. “If we wish to know sea ice in Antarctica, we can't usually wizz in locally — we unequivocally have to take a tellurian perspective.”

The other co-author is Kyle Armour, a UW partner highbrow of windy sciences and oceanography. The investigate was saved by a National Science Foundation and a National Oceanographic and Atmospheric Administration’s Climate and Global Change Postdoctoral Fellowship Program, administered by a University Corporation for Atmospheric Research’s Cooperative Programs for a Advancement of Earth System Science.

Source: University of Washington

Comment this news or article