Over 7.5 trillion tonnes decline in Antarctica's ice shelves since 1997, half show 'no sign of recovery'

Leeds, UK

A recent study conducted by scientists at the University of Leeds has uncovered a concerning trend in Antarctica, where over 40 per cent of the ice shelves have significantly diminished since 1997. What is shocking is that nearly half of these ice shelves display "no signs of recovery" and that this phenomenon is closely linked to climate change.

The researchers' calculations indicate that between 1997 and 2021, the western part of Antarctica lost a staggering 67 trillion tonnes of ice, while the eastern side saw a gain of 59 trillion tonnes. However, the net outcome is a substantial ice loss of 7.5 trillion tonnes during this period.

Also Read | Human ancestor Neanderthals hunted Cave Lions as fierce fighters: Study

This imbalance is due to the influence of warm water in the western region causing ice melting, while the eastern area remains relatively stable or even gains ice due to colder water conditions, Guardian reported. 

Impact on ocean currents

Ice shelves, situated at the terminus of glaciers, serve to impede the flow of glacial ice into the sea.

As these ice shelves shrink, they release larger volumes of freshwater into the ocean, which can disrupt the critical currents of the Southern Ocean.

This disruption has a far-reaching impact on ocean circulation, which can, in turn, affect global climate patterns.

Dr. Benjamin Davison, an Earth observation expert and the lead researcher, reportedly said, “There is a mixed picture of ice-shelf deterioration, and this is to do with the ocean temperature and ocean currents around Antarctica."

“The western half is exposed to warm water, which can rapidly erode the ice shelves from below, whereas much of east Antarctica is currently protected from nearby warm water by a band of cold water at the coast," he added. 

Satellite-based research

The study used satellite technology to monitor annual changes in the ice, even during the long polar nights when clouds obscure observations. More than 100,000 images captured from space were analysed to assess the health of Antarctica's ice shelves, which are of global significance.

Also Read | Researchers 'virtually unwrap' ancient scrolls charred by Mt Vesuvius in 79 AD

The 67 trillion tonnes of freshwater released into the ocean over the 25-year period is not only a concerning sign of ice shelf instability but also has repercussions for the world's ocean currents, which are instrumental in transporting heat and nutrients globally.

Watch | Israel-Palestine War: Iran denies role in Hamas attack on Israel

Davison said, “We expected most ice shelves to go through cycles of rapid, but short-lived shrinking, then to regrow slowly. Instead, we see that almost half of them are shrinking with no sign of recovery.”