This Enormous Ice Shelf Has Broken Up – And It’s Revealed A Mysterious Primeval Ecosystem

Somewhere in the frozen expanse of the Antarctic, a vast sheet of ice breaks off from a peninsula and drifts out into the sea. But as the gap between them widens, a new world is slowly revealed – one that might not have seen daylight in 120,000 years.

Covering an area equivalent to that of Mexico and the United States combined, Antarctica stretches over almost 5.5 million square miles. But for all of its size, the world’s coldest and most inhospitable continent has no indigenous inhabitants, and its vast landscapes are completely devoid of cities and towns.

And because of this isolation, Antarctica remains the last true wilderness on planet Earth. Here, seals, penguins and whales far outnumber the handful of human inhabitants who make the long trek in order to study the continent’s many secrets.

Moreover, with a staggering 98 percent of the continent’s surface covered in ice, Antarctica holds its mysteries close to its chest. But every year, more and more of that ice is melting, revealing things that have been hidden for hundreds of thousands of years.

Image: Rob Jones/National Science Foundation via Getty images

Even though temperatures in Antarctica have been known to drop as low as -128° F, there are still some brave souls who spend sustained periods of time on its frozen plains. At the height of summer, in fact, as many as 4,000 scientists and researchers call the continent home.

During the mid 1990s these researchers began to report something strange that was happening in a region known as the Larsen Ice Shelf. Located in the Weddell Sea, this 30,000 square mile sheet of ice hugs the Antarctic Peninsula’s eastern coast.

In 1995 the northernmost section of ice, known as Larsen A, disintegrated. But because conditions were so tough, it would be half a decade before scientists could properly investigate. Then, in 2002 later Larsen B, the next section of ice shelf, also began to break off into the Weddell Sea.

This time, the shift was even more dramatic. Beginning on January 31, 2002, some 1,250 square miles of ice broke off from the main shelf. For perspective, this is an area approximately the size of Rhode Island, with a depth of some 720 feet. Twelve years later, scientists were finally able to study the site of this catastrophic event close up.

Image: Torsten Blackwood – Pool/Getty Images

Researchers subsequently concluded that warm currents, melting ice and higher temperatures all had a role to play in the break up of Larsen B. However, it was the accidental findings of an earlier expedition that really set the scientific community talking.

In a paper published in 2005 a team from the U.S. Antarctic Program detailed a fascinating discovery in the region of Larsen B. While investigating sediment on the seabed, they were surprised to stumble upon a vibrant ecosystem some 2,600 feet beneath the surface of the waves.

What’s more, the Larsen Ice Shelf was only just beginning to reveal its secrets. In July 2017 researchers reported that further change was afoot in Larsen C, currently one of the biggest ice shelves in Antarctica. That month, a massive 2,240 square mile section of ice separated from the main shelf and began to drift away.

The resulting iceberg was apparently so large that it reduced the size of the Larsen C ice shelf by around 12 percent. According to scientists, its dramatic formation was the result of a natural process, rather than a sign of climate change. And as it carried a trillion tons of ice out into the Weddell Sea, it left something fascinating behind.

In fact, the breakup of Larsen C exposed a section of sea floor that had been concealed beneath the ice for as many as 120,000 years. Previously, the area had been in a state of almost total isolation. Starved of light, there were only weak currents connecting it to the wider ocean.

And for scientists, these conditions provide a unique opportunity. “It’s just a fantastic, unknown area for scientific research,” Susan Grant, a marine biologist at the British Antarctic Survey, told Live Science. “We know very little about what might or what might not be living in these areas, and especially how they might change over time.”

For Grant, it’s a subject close to her own heart. Along with co-worker Phil Trathan, she led a campaign to ensure that unique regions such as this could be preserved for further research. And in 2016 the Commission for Conservation of Antarctic Marine Living Resources took the steps necessary to make that happen.

As the first area to fall under the agreement, the newly revealed section of Larsen C will enjoy a ban on commercial activity for a minimum of two years. Meanwhile, scientists are eager to find out what the region can teach us about life on Earth.

As events such as this are likely to occur more frequently, opportunities to learn about them are being welcomed by the scientific community. Grant feels that one of the most exciting elements is the chance to study how local fauna adapts to these evolving ecosystems.

“There’s this vast area which has been covered for thousands of years,” Grant explained. “We know the physical changes are likely to be huge when the ice moves away, and the ecosystem is likely to change along with that.” Indeed, previous studies of the Larsen Ice Sheet have revealed that life in these regions begins to transform soon after the thick ice covering them falls away.

“You’ll have sunlight, you’ll have phytoplankton, and you’ll begin to get zooplankton and fish in there pretty quickly,” Trathan explained. “You’ll probably also get sea birds, and marine mammals are going to begin to forage in that area.”

Image: LARSEN, HOEKON MOSVOLD/AFP/Getty Images

For now, the challenge is to raise funds for an expedition before the newly revealed ecosystem changes beyond recognition. According to Nature, this could be as early as 2018, when a South Korean mission en route to the South Shetland Isles may visit the region. In the meantime, scientists can only speculate about what might be waiting to be discovered.