A Saltier Southern Ocean Could Cause More Melting Ice in Antarctica

The merger of the Antarctic Sea Ice has already had serious consequences for the Southern Ocean, from the loss of its habitats to the increase in its sea level to the intensification of its storms and its serious weather conditions. But it turns out that things can always take a turn for the worst.

A new study in the Proceedings of the National Academy of Sciences Note that the surface of the southern ocean suddenly becomes more salty rather than cooler, because more and more antarctic sea ice is lost. According to study authors, this trend started in 2015 and surprises scientists, spelling problems for remaining sea ice.

“More salty surface waters allow deep oceanic heat to rise more easily, melt the sea ice from below,” said Alessandro Silvano, study author and researcher at the University of Southampton, according to a press release. “It is a dangerous feedback loop: less ice leads to more heat, which leads to even less ice.”

Find out more: The antarctic ice cap formed by an ideal coincidence

Sudden maritime change

Antarctic sea ice has merge for decades, and for a large part of this time, this merger made the surface of the southern ocean cooler, maintaining the ice that still survives. (In fact, a cooler ocean surface supports the much more salty ice, trapping the heat in the deep sea and saving the ice which is always on the surface of the fusion below.)

But now Silvano and a team of other researchers have discovered that the surface of the southern ocean has stopped becoming cooler and has started to become salty, leaving the ice that is still there at much larger risks.

Solving their data from satellites and submersible robots, study authors have discovered that an increase in salinity on the surface of the southern ocean has been maintained since 2015. Since then, the ice expanses that could cover the surface of the Greenland have melted, and a single open ocean spot – Polynya Maud Rise – reappeared in the Weddell Sea for the first time since the 1970s, covering an area about four times that of Wales.

“The return of Maud Rise Polynya reports how unusual the current conditions are,” said Silvano in the press release. “If this salty and low ice state continues, it could permanently reshape the southern ocean – and with it, the planet. The effects are already global: stronger storms, warmer oceans and narrowing habitats for penguins and other iconic antarctic wild animals. »»

Find out more: The Antarctic glacier surprised to make a hacking of ice to his neighbor

A challenge for current climate change models?

Before the new study, it was thought that the Antarctic Sea Ice would be maintained with warming, at least for a while. Although the increase in temperatures would melt part of the ice, the fusion would protect what was left, or at least, it was thought, by making the surface of the ocean fresher. This would increase the stratification of the ocean, separating the warmer waters from the deep ocean of the cooler waters of the surface ocean, thus preventing the remaining ice to melt.

“The previous projections have underlined an improved surface refreshment and a stronger ocean stratification, which could have supported a sustained sea ice coverage,” said Adityya Narayanan, another study author and researcher at the University of Southampton, according to the press release. “Instead, a rapid reduction in sea ice – an important reflector of solar radiation – has occurred, potentially accelerating global warming.”

According to the team, work further must be done to determine Motor forces Behind this change. However, until these forces are identified, the new study stresses that there are still surprises associated with the worsening of climate change – surprises that are crucial to monitor and integrate into current climate change models.

“The new results suggest that our current understanding could be insufficient to predict future changes,” said Alberto Naveira Garabato, another study author and professor at the University of Southampton, according to the press release. “This makes the need for satellite and in situ surveillance all the more urgent, so that we can better understand the engines of recent and future changes in the ice system.”

Find out more: Chicago’s size iceberg stands out from the ice cap, revealing a flourishing ecosystem

Sources of articles

Our writers at Discovermagazine.com Use studies evaluated by high -quality peers and sources for our articles, and our publishers examine scientific precision and editorial standards. Review the sources used below for this article:

Sam Walters is a journalist covering archeology, paleontology, ecology and the evolution of Discover, as well as an assortment of other subjects. Before joining the Discover team as a deputy editor in 2022, Sam studied journalism at the Northwestern University in Evanston, Illinois.