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10 MOST Recent Scientific Discoveries in Antarctica

 

By: Patrick J. Kiger

TOP 10 RECENT SCIENTIFIC DISCOVERIES IN ANTARCTICA

From the time that explorers first glimpsed Antarctica in the early 1800s, people have wanted to know more about the mysterious frozen continent at the bottom of the world. What was underneath the ice? How could living things even exist in a place with such an extreme climate? Starting in the late 1950s, scientists began to probe Antarctica’s mysteries in earnest, with efforts such as the U.S. Antarctic Program and Antarctica New Zealand, which operates Scott Base. Over the three decades in particular, researchers have made scores of important discoveries. Here are 11 that are particularly insightful.

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1. Dinosaurs once lived in Antarctica. In the mid-1980s and early 1990s, scientists discovered multiple sets of fossilized remains of the reptiles who once ruled the planet. The finds established that dinosaurs had lived on the southernmost continent as far back as 200 million years and as recently as 75-to-80 million years ago. As a New York Times account of the discovery explains, it was possible for the creatures to survive there because the planet’s temperature was 50 degrees warmer in those days, and because the Antarctic land mass was in a different spot then—in the middle of what is now the southwest Pacific Ocean.

2. A meteorite found in Antarctica contains possible evidence of ancient life on Mars. With its vast, largely undisturbed expanse, Antarctica is a great place to find meteorites. In 1996, scientists from NASA and Stanford University revealed that a potato-sized meteorite, which had originated on Mars and landed in Antarctica 13,000 years ago, contained what appeared to be fossilized specimens of ancient microbial life on the Red Planet.

3. Antarctica is the best listening spot on the planet for earthquakes. In 2003, data proved that National Science Foundation’s Amundsen-Scott South Pole Station, which has seismometers instruments placed in holes bored 1,000 feet, is the best place on Earth to detect the vibrations that quakes send through the Earth. That’s because it’s at the bottom of the Earth’s axis, and can detect quake waves without interference from the Earth’s spinning motion.

4. There’s an active undersea volcano off the Antarctic coast. In 2004, a research ship sent to investigate the collapse of the Larsen B ice sheet made an unintended discovery. Near the Antarctic Peninsula, the continent’s northernmost point, scientists detected a previously unknown, 2,300-foot tall volcano rising up from the sea floor to within 900 feet of the water surface. Temperature probes moving along the sea found evidence of geothermal heating of seawater, which along with other evidence indicate that the volcano has been active recently.

5. Antarctica may have been connected to North America. In an article published in Science in 2008, researchers presented the case that a lone granite boulder, discovered atop an Antarctic glacier, supported the theory that parts of Antarctica were connected to North America in an ancient supercontinent that’s been dubbed Rodinia, which formed between 1 billion and 1.2 billion years ago, and lasted for more than 250 million years. Chemical and isotopic tests of the boulder revealed that its chemistry was very similar to a belt of igneous rock that otherwise has only been found in North America.

Photograph by Mihai Maxim

An iceberg in Antarctica.

6. Antarctic icebergs are hotspots for aquatic life. In a study published in the journal Science in 2007, researchers revealed that icebergs calved by the Antarctic ice sheets contain trapped material from the soil that they gradually release into ocean waters. As a result, the icebergs create a halo of nutrients around them that supports a range of aquatic life, from phytoplankton and krill to communities of sea birds.

7. Antarctica once was a refuge for animals from an ancient mass extinction. In 2009, scientists identified fossilized remains discovered in Antarctica decades before as belonging to Kombuisia Antarctica, which was a cat-sized, egg-laying distant relative of modern mammals that lived about 250 million years ago. What’s particularly interesting about the ancient species is that it apparently survived a mass extinction event, which may have been the result of global warming, by relocating southward from Africa to Antarctica’s cooler climate. Back then, Antarctica was part of another supercontinent called Pangea, which formed between 272 and 299 million years ago and broke apart again about 200 million years ago.

Photograph by Selphiek

A glacier in Antarctica.

8. Antarctica’s glaciers are in an irreversible retreat due to climate change. In a 2014 study, scientists analyzed 40 years’ worth of data on six glaciers sending ice streams into Antarctica’s Amundsen Bay. They concluded that the glaciers were being eroded by warmer ocean water that was eating away at their fronts, and that the process had advanced past what University of California, Irvine researcher Eric Rignot, called “the point of no return.” A separate study done about the same time concluded that one such glacier, the Thwaites Glacier, could vanish completely in 200 to 500 years.

9. There’s a valley deeper than the Grand Canyon hidden under the ice of West Antarctica.Scientists using radar to probe beneath the ice of west Antarctica have made an amazing discovery. In a paper published in 2014, they described a massive valley nearly 200 miles long, 15-feet across and two miles deep—deeper than the Grand Canyon—that lay beneath their feet.

10. Life exists thousands of feet under Antarctica’s ice. Researchers drilled a hole more than 2,400 feet into Antarctica’s Ross Ice Shelf and sent a robotic probe down to explore an area that gets little sunlight. They expected that those waters would be devoid of life, except perhaps for a few microbes with slow metabolic rates. Instead, according to a 2015 Scientific American article, they made an astounding discovery—tiny fish and other aquatic creatures living under the thick ice. What the animals relied upon for food was unclear, but one theory was that bacteria at the bottom of the food chain were powered by chemical energy, in the form of methane seeping upward from ancient sediments.

Bonus Fact: Bubbles in Antarctic ice reveal the composition of the ancient Earth’s atmosphere.Scientists have drilled into the Antarctic ice and removed cores that contain bubbles that froze as long as one million years ago. In a paper published in 2015, the scientists described how the bubbles provided evidence of a strong link between carbon dioxide levels in the atmosphere and glacial cycles. One alarming finding: C02 levels in the ancient air never rose above 300 parts per million—less than the 400 parts per million threshold that the planet recently surpassed. Climate scientists attribute the latter increase in atmospheric carbon largely to the burning of fossil fuels.

These and other discoveries have helped scientists to see Antarctica not as a barren, isolated wilderness, but as a place that’s been interconnected with the rest of the planet and plays an important part in its natural history. They’ve also given us revealing insights into the extent to which human-driven climate change is altering both Antarctica and the Earth as a whole.

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