Scientists have finally identified the ‘triple whammy’ behind Antarctica’s dramatic collapse, shedding new light on the chain reaction that has pushed its sea ice to record lows.

A new study found that a combination of deep ocean heat, powerful winds and a self-reinforcing feedback loop destabilised the Southern Ocean surrounding Antarctica after 2015. Those factors have prevented the sea ice from recovering.

Researchers warn that the losses could disrupt ocean currents, accelerate warming and contribute to rising sea levels worldwide. The study, led by researchers at the University of Southampton, found the collapse unfolded in three stages over the past decade.

Lead author Aditya Narayanan says the losses were so extensive they wiped out an area of sea ice nearly the size of Greenland. “What started as a slow build-up of deep-sea heat under the Antarctic sea ice was followed by a violent mixing of water, ending in a vicious cycle where it’s too warm to let ice recover,” he explains.

Around 2013, strengthening winds started drawing warm, salty water from the deep ocean – known as circumpolar deep water – closer to the surface beneath Antarctic sea ice. Soon, powerful winds churned that heat upward, triggering rapid sea ice melting in East Antarctica.

Since 2018, the region has become trapped in a feedback loop. With less sea ice left to melt, the ocean surface remains warmer and saltier. That makes it harder for new ice to form, the scientists say.

The research also found some big differences in how the losses are unfolding across the continent. In East Antarctica, the decline is largely due to warm water rising from the deep. In West Antarctica, warm air from the subtropics and persistent cloud cover trapped heat near the ocean surface, contributing to major melting events during the summers of 2016 and 2019.

From 2002 to 2020, Antarctica lost roughly 149 billion metric tons of ice each year, according to NASA. Yet even as the sea ice melts and Antarctica becomes more unstable, more people are travelling there to see it.

According to the International Association of Antarctica Tour Operators (IAATO), around 122,000 people visited Antarctica in 2024, up from roughly 44,000 in 2017.

But the boom in last chance tourism is putting extra pressure on an already fragile ecosystem. As visitors climb, so do the risks of contamination, invasive species and disease outbreaks, scientists and environmental groups warn.

Source: Euronews

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