After 50 years of mystery, the mystery behind the appearance of a hole the size of Switzerland in Antarctic ice has been solved.

After 50 years of mystery, an international group of scientists has discovered the process by which unusual holes form in Antarctic sea ice.

Each winter in Antarctica, the continent undergoes dramatic changes as the sea ice surrounding the continent expands outward, effectively doubling the size of Antarctica.

But during the winter of 2016-2017, an unusual hole the size of Switzerland, called a poliña, formed in the sea ice.

The crater was named Maud Rise Polinya, after the oceanic plateau, or underwater mountain, located beneath it in the Weddell Sea.

They ultimately formed as a result of a combination of winds, ocean currents, and underwater topography that created ideal salinity concentrations to melt sea ice, according to the new study.

Mode Rise Polinya’s history goes back even further than 2016. Maud Rise Polinya was born during his 1970s, especially from 1974 until he was first identified by Earth exploration satellites during the winter of 1976.

Scientists thought that the pollinya returned every winter, but this was not true and only reappeared sporadically and for short periods.

In the winters of 2016 and 2017, the Circumpolar Current in the Weddell Sea was stronger than usual. As a result, the bottom waters around Maud Rise rose, bringing warmer, saltier water to the surface.

At that time, Maudrise Polinya lasted several weeks and reached a considerable size. According to NASA, the crater’s area expanded from 9,500 square kilometers measured in mid-September 2017 to about 80,000 square kilometers by the end of October 2017.

The experts wanted to know the mechanisms that allow mode-rise polynya to form and persist for such long periods of time.

Recent studies have concluded that the polynya was caused by the rise of warm, salty bottom water due to circulating currents around the Weddell Sea.

“These currents help explain how sea ice melts,” explained research team member Professor Fabian Roque, a physical oceanographer at the University of Gothenburg in Sweden, in a statement. But “for Polinya to continue, there needs to be a different process,” he says. The cooling of surface water that occurs when ice melts should prevent surface water from mixing with warm salt water.

“There has to be extra salt somewhere,” he continued.

Using data from satellites, independent buoys, and marine mammals, the research team found that turbulent eddies around Maud Rise brought more salt to the region, which was then transported to the surface through a process called Ekman transport. he suggested.

Through the process of Ekman transport, water moves at a 90 degree angle to the winds aloft, influencing ocean currents.

“Polinya traces can remain in the water for years after they form,” said study team member Sarah Gale, a professor at the University of California, San Diego. “It could change how water moves and ocean currents transport heat to the continents. The dense water that forms here could spread across the oceans.”Global”.

The new study was published online May 1 in the journal Science Advances.

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