Massive Southern Ocean Current Discovered [View All]

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ScienceDaily (Apr. 26, 2010) — A deep ocean current with a volume equivalent to 40 Amazon Rivers has been discovered by Japanese and Australian scientists near the Kerguelen plateau, in the Indian Ocean sector of the Southern Ocean, 4,200 kilometres south-west of Perth.


In a paper published in Nature Geoscience, the researchers described the current -more than three kilometres below the Ocean's surface -- as an important pathway in a global network of ocean currents that influence climate patterns.

"The current carries dense, oxygen-rich water that sinks near Antarctica to the deep ocean basins further north," says co-author Dr Steve Rintoul from the Antarctic Climate and Ecosystems CRC and CSIRO's Wealth from Oceans Flagship.

"Without this supply of Antarctic water, the deepest levels of the ocean would have little oxygen.

"The ocean influences climate by storing and transporting heat and carbon dioxide -- the more the ocean stores, the slower the rate of climate change. The deep current along the Kerguelen Plateau is part of a global system of ocean currents called the overturning circulation, which determines how much heat and carbon the ocean can soak up."

While earlier expeditions had detected evidence of the current system, they were not able to determine how much water the current carried. The joint Japanese-Australian experiment deployed current-meter moorings anchored to the sea floor at depths of up to 4500m. Each mooring reached from the sea floor to a depth of 1000m and measured current speed, temperature and salinity for a two-year period.

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http://www.sciencedaily.com/releases/2010/04/100427101234.htm