It’s Not What You Think

 December 31, 2021

Scientists Have Found an Incredible Secret Below the Ice of Antarctica

The southernmost continent in the world, Antarctica, continues to be a source of fascination and mystery for people around the globe. Our knowledge of this frozen continent began on January 17, 1773, when famed explorer James Cook became the first to cross the Antarctic Circle, which surrounds it. Cook is pictured in the painting below.

On January 27, 1820, a group of Russian explorers became the first to lay eyes on Antarctica. They sighted an ice shelf that bordered what is now known as Queen Maud Land. While our understanding of the last discovered continent has progressed considerably since then, what do we really know about Antarctica?

Due to its harsh climate and remote location, Antarctica is the loneliest and least visited of the seven major continents. Spanning 5.5 million square miles, it is home to many penguins, seals, and whales, but has no permanent human residents. Nevertheless, Antarctica has remained a constant source of fascination ever since it was first discovered. Each year, small groups of researchers and tourists continue to visit the frozen landmass.

A Startling Discovery

Thousands of miles away in the Golden State of California, scientists have made a shocking discovery about Antarctica. This discovery is not about the surface of the continent but about what lies many miles below the ice.

Photo Courtesy: Joe Mastroianni, National Science Foundation/Wikimedia Commons

Given that Antarctica is nearly twice the size of Australia, it is no surprise that this has only now been found. When one takes into account the increasing dangers of climate change, the discovery becomes even more unsettling.

This scientific breakthrough came as a result of a collaborative effort between several institutions. In 2014, these collaborators used advanced technology and physics to map out the entire continent.

Five years after the creation of the map, these scientists made their findings public for the first time. While the data was highly informative, it also revealed chilling implications about the effects of climate change on Antarctica.

For years, scientists have been able to peer below the surface of Antarctica using radar technology. By sending out pulses of microwave radiation, they have systematically mapped the terrain beneath the dense sheets of ice.

Unfortunately, this technology has its limitations. The depth of certain regions in Antarctica makes it impossible for the microwaves to accurately determine what lies beneath. Instead of reaching the bottom, the signals are deflected by trenches, valleys, and other geological formations.

In December 2019, the moment of truth finally arrived for Antarctica and its mysterious underworld. A team of international researchers—hailing from the United States, Europe, Australia, and Asia—revealed the findings from their extensive project.

Known as BedMachine Antarctica, its objective was to map the area beneath the surface as accurately as possible. In preparation, researchers reviewed records dating back almost 50 years. The radar data compiled from these records covered nearly a million miles.

Although this legacy data was insufficient to complete the project, it provided a crucial starting point. With this foundation, the scientists began assembling their comprehensive map of Antarctica. To fill in the gaps, they turned to the principle of mass conservation.

This scientific law, discovered by Mikhail Lomonosov (pictured above), states that if any closed system is never exposed to external forces, then it remains constant. In essence, since matter cannot be created or destroyed, it stays unchanged in a closed system—such as the terrain beneath Antarctic ice.

With mass conservation in mind, the scientists estimated how much ice lies beneath Antarctica by tracking how it flows across the continent. By knowing the volume and speed of ice entering valleys, they could fill in the gaps where radar data was limited.

Not only did the team determine the amount of ice in these valleys, but they also discovered how deep they extend underground. By "pulling back the curtain," they revealed the structure and contours of the valley floor. Through their tireless efforts, the most expansive and accurate map of Antarctica ever created came to be.

The results of their study appeared in Nature Geoscience, a journal published by Nature Research. On December 13, 2019, a day after the article’s publication, the findings were presented at a meeting of the American Geophysical Union.

The study’s conclusions are directly tied to Queen Mary Land, part of the Australian Antarctic Territory located in East Antarctica near the Southern Ocean.

Also known as the Queen Mary Coast, this area was discovered in 1912 by the Australian Antarctic Expedition and named after Mary of Teck, Queen of the United Kingdom and wife of King George V. She was the grandmother of Queen Elizabeth II, and is shown in the painting above.

One of the most important landmarks in Queen Mary Land is the Denman Glacier. This enormous glacier spans roughly 12 miles and dominates the remote landscape.

As shown in the map above, several other glaciers occupy the area—such as Reid Glacier, Scott Glacier, Northcliffe Glacier, and Apple Glacier. However, none of these rivals Denman Glacier’s hidden secret.

A Record-Breaking Canyon

Beneath the Denman Glacier, the researchers discovered a massive canyon extending 11,500 feet below sea level. While its very existence is impressive, its depth is the most significant feature—it is currently the lowest natural point ever discovered on land.

By comparison, the Byrd Glacier, located nearly 1,400 miles away in the Ross Dependency, reaches a depth of 9,121 feet below sea level. The Ross Dependency is named after Sir James Clark Ross and is administered by New Zealand.

Previously, the lowest known land point was in Asia, at the southern end of the Jordan Valley in Israel, where it meets the Dead Sea. This region lies 1,411 feet below sea level. The canyon beneath Denman Glacier surpasses it by almost eight times.

Interestingly, the lowest point on Earth overall is much deeper than even the Denman Glacier. In the depths of the Pacific Ocean, just east of the Mariana Islands, lies the Mariana Trench, believed to reach 36,037 feet at its deepest point.

While the depth of the Mariana Trench is undeniably awe-inspiring, the Antarctic canyon is equally remarkable, considering it lies beneath a glacier on land. Though it was long suspected that something lay beneath Denman Canyon, no one had managed to map it—until now.

The researchers’ ingenuity and technical skill proved vital to achieving this groundbreaking feat. By overcoming the limits of conventional radar technology, they unlocked a major geographic discovery.

Challenges and Comparisons

Although the depth was a major revelation, it was not the only one. Surprisingly, there are valleys around the world that are similarly deep yet remain above sea level.

For example, the Yarlung Tsangpo Grand Canyon, which runs along the Yarlung Tsangpo River in the Xizang Autonomous Region of southwestern China, reaches nearly 20,000 feet at its deepest point.

What made mapping the Antarctic canyon so challenging? Multiple trenches cut through the valley floor, causing radar microwaves to bounce off irregular surfaces. This made it almost impossible to determine where the actual bed of the glacier was.

But this diverse and skilled team of researchers succeeded in overcoming what had once seemed insurmountable.