Antarctica has a huge, completely hidden mountain range. New data reveals its birth over 500 million years ago

The Gamburtsev Subglacial Mountains are hidden by deep ice. Merkushev Vasiliy/Shutterstock Jacqueline Halpin, University of Tasmania and Nathan R. Daczko, Macquarie UniversityHave you ever imagined what Antarctica looks like beneath its thick blanket of ice? Hidden below are rugged mountains, valleys, hills and plains. Some peaks, like the towering Transantarctic Mountains, rise above the ice. But others, like the mysterious and ancient Gamburtsev Subglacial Mountains in the middle of East Antarctica, are completely buried. The Gamburtsev Mountains are similar in scale and shape to the European Alps. But we can’t see them because the high alpine peaks and deep glacial valleys are entombed beneath kilometres of ice. How did they come to be? Typically, a mountain range will rise in places where two tectonic plates clash with each other. But East Antarctica has been tectonically stable for millions of years. Our new study, published in Earth and Planetary Science Letters, reveals how this hidden mountain chain emerged more than 500 million years ago when the supercontinent Gondwana formed from colliding tectonic plates. Our findings offer fresh insight into how mountains and continents evolve over geological time. They also help explain why Antarctica’s interior has remained remarkably stable for hundreds of millions of years. ...
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Antarctica’s hidden threat: meltwater under the ice sheet amplifies sea-level rise

LouieLea, Shutterstock Chen Zhao, University of Tasmania and Ben Galton-Fenzi, Australian Antarctic DivisionOne of the biggest challenges in predicting Antarctica’s deeply uncertain future is understanding exactly what’s driving its ice loss. A vast network of lakes and streams lies beneath the thick ice sheet. This water can lubricate the ice, allowing it to slide more rapidly toward the ocean. Our new research shows “subglacial water” plays a far larger role in Antarctic ice loss than previously thought. If it’s not properly accounted for, future sea-level rise may be vastly underestimated. Including the effects of evolving subglacial water in ice sheet models can triple the amount of ice flowing to the ocean. This adds more than two metres to global sea levels by 2300, with potentially enormous consequences for coastal communities worldwide. How hidden lakes threaten Antarctic Ice Sheet stability. (European Space Agency) Understanding the role of subglacial water Subglacial water forms when the base of the ice sheet melts. This occurs either due to friction from the movement of the ice, or geothermal heat from the bedrock below. The presence of subglacial water enables ice to slide over the bedrock more easily. It can also cause further melting under ice shelves, leading to...
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