A new map reveals the landscape beneath Antarctica in unprecedented detail

A new map has revealed the landscape beneath Antarctica’s ice in unprecedented detail, something scientists say will greatly improve our understanding of the icy white continent.

Researchers are using satellite data and the physics of how Antarctica’s glaciers move to figure out what the continent looks like under the ice.

They have found evidence of thousands of undiscovered hills and ridges, and say their maps of some of Antarctica’s hidden mountains are clearer than ever.

While the maps are subject to uncertainty, researchers believe the new details may shed light on how Antarctica is responding to climate change — and what sea-level rise means.

“It’s like before you had a grainy pixel film camera, and now you get a proper zoom-in digital image of what’s really going on,” lead author Dr Helen Ockenden, a researcher at the University of Grenoble-Alpes, told BBC News.

Thanks to satellites, scientists have a better understanding of Antarctica’s icy surface – but what lies beneath remains a mystery.

In fact, more is known about the surface of some planets in our Solar System than most of the “underbelly” of Antarctica – the topography under the ice sheet.

But researchers now have what they believe is the most complete, detailed map of that lower abdomen ever made.

“I was really excited to look at that and just see the whole bed of Antarctica at once,” said Prof Robert Bingham, a glaciologist at the University of Edinburgh who co-authored the study. “I think that’s amazing.”

Traditional measurements from the ground or air use radar to “see” beneath the ice – which is up to three miles (4.8km) thick in places – often along individual survey lines or tracks.

But these paths can be ten kilometers apart – leaving scientists to fill in the gaps.

“If you imagine the Scottish Highlands or the European Alps covered in ice and the only way to understand their shape is to occasionally fly a few kilometers away, there’s no way you can see all these sharp mountains and valleys that we know are there,” said Bingham.

So the researchers used a new method, which combined their knowledge of the ice surface from satellites and their understanding of how the ice moves from physics – and checked it against previous tracks.

“It’s a little like if you’re kayaking in a river, and there are rocks under the water, sometimes there are eddies on the surface, which can tell you about the rocks under the water,” explained Ockenden.

“And ice obviously flows very differently from water, but even so, when ice flows on a ridge or a rocky hill (…) that can be seen in the topography of the surface, but also in the speed as well.”

While we know about the great mountains of Antarctica, the new method of scientists has revealed tens of thousands of previously unseen hills and ridges, as well as many details around some of the mountains and canyons buried under the ice.

“I think it’s going to be really interesting to look at all these new landscapes and see what’s out there,” Ockenden said.

“It’s like when you see a map of the topography of Mars for the first time, and you’re like, ‘whoa, this is really interesting, this looks like Scotland,’ or ‘this looks like something I’ve never seen before’.”

An interesting discovery is a deep channel cut into the bed of Antarctica in an area called the Maud Subglacial Basin.

The channel is on average 50m deep, 6km wide and runs for almost 400km (about 250 miles) – roughly the distance from London to Newcastle as the crow flies.

The researchers’ new map may not be the last. It relies on assumptions about exactly how the ice flows which, like any method, has uncertainties.

And more is being discovered about the rocks and sediments that lie beneath the ice.

But other researchers agree that, combined with additional surveys from the ground, air and space, the maps are a valuable step forward.

“This is a useful product,” said Dr Peter Fretwell, senior scientist at the British Antarctic Survey in Cambridge, who was not involved in the new study but was heavily involved in previous mapping.

“This gives us an opportunity to fill in the gaps between surveys,” he added.

A more detailed understanding of all the ridges, hills, mountains and channels could improve computer models of how Antarctica will change in the future, the researchers said.

That’s because these landforms and features ultimately shape how fast the surface glaciers move, and how quickly they can retreat. a warm climate.

And that’s important because the future speed of Antarctica’s melting is widely considered one of the biggest unknowns in climate science.

“(This study gives) us a better picture of what will happen in the future and how quickly the Antarctic ice sheet will contribute to global sea level rise,” Fretwell agreed.

The study was published in the academic journal, Science.