New high-resolution maps of the seafloor between Tasmania and Antarctica reveal a series of underwater volcanoes whose towering peaks may shape ocean currents above.
Undersea volcanoes or seamounts lie 13,000 feet (4,000 meters) below the waves, directly in the path of the Earth’s strongest ocean current, the Antarctic Circumpolar Current, which flows in a clockwise direction Antarctica and acts as a barrier, helping to keep the icy continent frozen. Now, scientists have mapped areas where the barrier appears to be leaking, allowing vortices of warm water to reach the Antarctic coast.
The region is “a gateway for heat transport to Antarctica, causing ice melt and sea level rise.” Benoit LeGrasiChief scientist of the surveying and mapping expedition and sea level scientist at the University of Tasmania said in the report statement.
The leak is nothing new, but scientists hope the new map will help predict how the leak will evolve as the ocean warms, the statement said. climate change and meltwater pouring in southern ocean.
related: The Antarctic current, which provides nutrients and oxygen to 40% of the world’s deep oceans, has shrunk sharply
LeGrasi and his colleagues collected oceanographic data within the Circumpolar Current from the Australian research vessel Investigator. They also used new surface water and ocean topography from NASA and the French National Center for Space Research (SWOT analysis) satellites measure the height of the ocean surface from space to collect information on the seafloor.
Satellite measurements revealed a series of mountain ranges spanning 7,700 square miles (20,000 square kilometers) west of Macquarie Island and the tectonically active Macquarie Ridge.
“To our delight, we discovered a spectacular series of ancient seamounts, including eight long-dormant volcanoes with peaks reaching heights of 1,500 metres. [4,900 feet] Tall and has double vents,” Christopher YuleA doctoral student in marine geophysics at Australia’s James Cook University who participated in the expedition said in a statement. Four of the seamounts are new to science, Yule said.
The statement said the volcanoes formed nearly 20 million years ago and may have played a role in shaping ocean currents around Antarctica. “The Antarctic Circumpolar Current ‘feels’ the seafloor and mountains in its path, causing the current to ‘wobble’ when it encounters obstacles such as ridges or seamounts,” Helen PhillipsThe voyage’s co-chief scientist, Associate Professor of Oceanography at the University of Tasmania, said in a statement.
These oscillations create eddy or toroidal currents Caught by ocean currents. “Eddies, like the ocean’s weather systems, play an important role in transporting heat and carbon from the upper ocean to deeper layers, an important buffer against global warming,” Phillips said. “Understanding the depth and shape of the seafloor is important for It is critical that we quantify the impact of submarine mountains, hills and valleys on the Antarctic Circumpolar Current and the leakage of heat to Antarctica.”
Ultimately, Phillips added, mapping the Southern Ocean will provide clues about the extent of Antarctica’s ice melt and help predict the resulting sea level rise.
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