The deep ocean circulation that forms around Antarctica and supplies oxygen to the depths could collapse.
This is shown by the results of a recent study by an international team of scientists that modeled the amount of Antarctic deep water that would be produced under climate change under a “high emissions scenario” of greenhouse gases for the period up to 2050, according to ScienceDaily.
Such a decrease in this oceanic circulation will lead to “stagnation” of the ocean floor and further impacts on climate and marine ecosystems over the next centuries, the article notes.
Cold water sinking near Antarctica creates the deepest reverse circulation flow – a network of currents that spans the world’s oceans. The movement of water carries heat, carbon, oxygen and nutrients around the globe. This has an impact on climate, sea levels and the productivity of marine ecosystems.
About 250 trillion tons of cold, salty, oxygen-rich water sink into the deep ocean near Antarctica each year. This water then spreads north and carries oxygen to the depths of the Indian, Pacific and Atlantic oceans.
If the oceans had lungs, this would be one of them, scientists say.
This deep ocean current has remained relatively stable for thousands of years, but with increasing greenhouse gas emissions, this Antarctic circulation is predicted to slow down significantly over several decades.
Our modeling suggests that if global carbon emissions continue at their current rate, Antarctica’s circulation will slow by more than 40 percent over the next 30 years – and on a trajectory that appears to be collapsing, the researchers add.
In the event of the disappearance of this deep ocean current, the oceans at a depth of more than 4 thousand meters will “stagnate”.
This will lead to the retention of nutrients in the deep ocean, which will reduce the amount of nutrients available to support marine life near the surface of the ocean, scientists say.
In addition, modeling shows that this trend will also lead to a rapid warming of the ocean depths.
Direct measurements confirm that the heating of the deep ocean is indeed already ongoing, scientists say.
The study found that melting ice around Antarctica is making ocean waters nearby less dense, slowing down the Antarctic circulation. The melting of the Antarctic and Greenland ice sheets is expected to continue to accelerate as the planet warms.
We are talking about the possible long-term disappearance of the iconic water mass, scientists say. “Such profound changes in the ocean’s mechanism for reversing heat, fresh water, oxygen, carbon and nutrients will affect the oceans for centuries to come.
Source: sciencedaily
Scientists have calculated the amount of ice lost by Antarctica in 25 years
The glaciers of Antarctica have already been actively melting in the recent past.
Source: Racurs
I am David Wyatt, a professional writer and journalist for Buna Times. I specialize in the world section of news coverage, where I bring to light stories and issues that affect us globally. As a graduate of Journalism, I have always had the passion to spread knowledge through writing.