A recent study has revealed that over 40% of Antarctica ice shelves have experienced significant shrinkage since 1997, and nearly half of them show “no sign of recovery,” with these changes attributed to the ongoing climate crisis.
Researchers at the University of Leeds calculated that between 1997 and 2021, the western part of Antarctica lost approximately 67 trillion tonnes of ice, while the eastern side gained 59 trillion tonnes. This resulted in a net loss of 7.5 trillion tonnes of ice. The ice loss in the west is primarily due to the influence of warm water, which has been melting the ice. Conversely, in the east, the colder water has helped some ice shelves remain stable or even grow.
Ice shelves are located at the terminus of glaciers and function to decelerate the flow of ice into the sea. When these ice shelves diminish, glaciers release larger amounts of freshwater into the sea, potentially disrupting the currents in the Southern Ocean.
Dr. Benjamin Davison, the lead researcher and an expert in Earth observation, clarified, “The condition of ice-shelf deterioration varies and relates to the ocean temperature and currents around Antarctica.” The western portion faces exposure to warm water, which can swiftly erode the ice shelves from underneath, whereas a band of cold water along the coast currently shields much of East Antarctica from warm water.
To assess the ice’s health, scientists used satellites capable of penetrating the thick cloud cover during the long polar nights, examining more than 100,000 space images. The findings were published in the journal Scientific Advances.
The estimated 67 trillion tonnes of freshwater released into the ocean over 25 years can have far-reaching consequences, affecting ocean currents responsible for the transport of heat and nutrients globally.
Scientists believe that this ice loss is a direct consequence of the climate crisis, as natural variability would entail some ice regrowth. Dr. Davison noted, “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.”
Notably, a recent study from France suggested that Antarctica is warming at a rate nearly twice that of the rest of the world, surpassing the predictions of climate models. French scientists examined 78 Antarctic ice cores and reconstructed temperature data spanning the past 1,000 years.Their findings revealed that the continent’s warming trends exceed what one would anticipate from natural climate fluctuations.