In their new study, published in Nature Communications, the researchers say that the Antarctic ice sheet (Antarctica) It reached the point of no return in terms of ice cap loss earlier than previously thought.
“We may already be in the middle of this stage,” they add.
Which could have dire consequences when it comes to global sea level rise, and the natural environment that Antarctica’s animals depend on.
Back to the past
In order for researchers to reach these results, they went back to the past and researched the history of the continent over the past twenty thousand years – the last ice age – by studying the ice core extracted from the sea floor.
To understand the matter in a less complex way, scientists say that when the icebergs separate from the glaciers in Antarctica, they float in a main channel known as (Iceberg Alley), then the icebergs slip into the sea, and when they melt, debris stuck to these mountains accumulates on the sea floor, causing It gives researchers a history record about 3.5 kilometers underwater.
By combining this natural record of iceberg drift with computer models of ice sheet behavior, the team was able to identify eight stages of ice sheet retreat over the last thousands of years. that.
The study showed that the same pattern of sea rise occurs in each of the eight stages as well, with global sea levels affected for centuries and even a thousand years in some cases, and statistical analysis identified turning points for these changes.
A new turning point
The study findings bolster recent satellite images, which are only nearly 40 years old, as they show an increase in ice losses from the interior of the Antarctic ice sheet, not just changes in ice shelves that are already floating on the water.
If we compare the current shift in Antarctica’s ice in the same way as we interpret past events identified in the study, we may already be in the midst of a new tipping point, which we’ve seen in the Arctic in recent years, the researchers say.
“Our findings are consistent with a growing body of evidence suggesting that the acceleration of Antarctic ice-mass loss in recent decades may mark the irreversible beginning of ice sheet retreat and surface-level rise,” says geophysicist Michael Weber of the University of Bonn in Germany. the global sea in a large way.