According to a study published on Tuesday and cited by AFP, scientists have discovered a vast landscape that once had green hills and valleys hidden for millions of years under the ice of Antarctica.

The British and American researchers who made the discovery warn that the landscape, which is the size of Belgium, has remained intact for potentially more than 34 million years, but could be freed by melting ice caused by global warming.

“This is a landscape that no one has seen before,” Stuart Jamieson of Britain’s Durham University, lead author of the study published in Nature Communications, told AFP.

The researchers didn’t need new data to discover this, just a new approach to this terra incognita, located beneath the East Antarctic Ice Sheet, which is far less well-known than the surface of Mars.

To see what lay beneath it required sending radio waves into the ice by flying a plane over it and then analyzing the echoes, a method known as echo sounding.

But carrying out this operation on the scale of the Antarctic continent, which is larger than Europe, would be a serious challenge. The researchers therefore used existing satellite images of the surface to “track valleys and ridges” down to a depth of more than two kilometres, Stewart Jamieson explained.

Combining this data with radio waves produced an image of a river-crisscrossed landscape consisting of deep valleys and steep-topped hills similar to those found on Earth’s surface today.

“It was like looking out of an airplane window and seeing a mountainous region below,” explains the glaciologist, who likens the landscape to the Snowdonia region of North Wales.

Climate threat

This 32,000 square kilometer area was once forested and probably home to animals. Before the ice covers her and “freezes in time”.

It is difficult to determine exactly when the landscape was last exposed to the sun, but estimates suggest it was at least 14 million years ago. Professor Jamieson’s “hunch” is that Antarctica began to freeze more than 34 million years ago.

Earlier, researchers found a lake the size of a city under the Antarctic ice, and the authors of the study hope to discover even more landscapes.

Only global warming can threaten their last discovery.

Fortunately, the landscape is several kilometers from the edge of the ice sheet, which should protect it from future exposure to light.

Another reassuring factor is that this hidden world was not affected by ice retreat during earlier periods of warming, such as the Pliocene period, 3 to 4.5 million years ago.

But we still don’t know what the climate “tipping point” will be for the “runaway response” of ice melting, Professor Jamieson said.

On Monday, a study warned that the melting of the nearby West Antarctic ice sheet could accelerate significantly in the coming decades. Even if the world fulfills its obligations to limit global warming. (photo: TasFoto, Dreamstime.com)