Scientists sound alarm over little-known threat emerging from Antarctica: ‘Acting like a giant conveyor belt’

A shift in balance at the frozen edges of Antarctica could disrupt the balance in all of the world’s oceans — affecting weather patterns and even global food security.

What’s happening?

Researchers from the University of Queensland conducted high-resolution ocean-ice simulations of the Cape Darnley region to identify the factors that influence the formation of dense shelf water, which in turn affects ocean salinity and density.

They published a study that found the main drivers are accelerating ice-shelf melting and decreasing sea-ice formation. A shutdown of sea ice formation can result in a reduction of up to 36% in dense shelf water.

“This dense water sinks to the ocean floor where it flows northwards acting like a giant conveyor belt driving currents around the planet which influence the climate worldwide,” lead researcher Dr. David Gwyther explained, per the University of Queensland News.

When ice shelves melt faster, and sea ice becomes less stable, less dense shelf water is made, and the deep ocean system weakens — changes that affect global ocean systems and weather patterns.

Why is this concerning?

While the study is theoretical and based only on simulated scenarios, real-world changes happening in Antarctica are already affecting the planet.

The northward flow of the bottom water from Antarctica dropped by about 12% between 2000 and 2020, according to the National Oceanic and Atmospheric Administration.

Meanwhile, the Arctic sea ice loses about 13% of its mass each decade, the World Wildlife Fund reported. The loss of Arctic ice can lead to higher tides and a higher risk of disease.

Together, polar ice melt at both ends adds fresh water to the oceans and makes it harder for heavy water to sink.

The slower movement of dense water can alter ocean circulation, which may influence global currents and weather patterns, even in regions far from the poles. It may indirectly contribute to the rising temperatures that are now acting as steroids for extreme weather events.

Deep ocean changes due to polar ice melt can also affect marine biodiversity: Antarctica New Zealand noted that slow bottom movement limits the movement of oxygen and nutrients.

Changes in salinity can destabilize ecosystems. Ultimately, these fluctuations disrupt food chains that support coastal livelihoods and feed the world.

What’s being done about the issue?

Scientists continue to closely monitor polar ice and ocean systems to issue early warnings and develop solutions that can slow these detrimental effects.

Individuals can explore critical environmental issues and take local action to reduce the human activities that release air pollution, which speeds polar ice melt and slows sea ice formation.

Understanding how distant polar regions affect the lives of people worldwide is an important step toward protecting our oceans.

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