New stream that transports water to major ‘waterfalls’ discovered in the deep ocean

Norröna, quoted in Nature’s Communications On paper, measure upper ocean currents with an ADCP (Acoustic Doppler Current Profiler) installed in your helmet while you make a weekly round trip between Denmark, the Faroe Islands and Iceland. Credit: Erik Christensen – Own work, CC BY-SA 3.0, commons.wikimedia.org/w/index.php?curid=45707529 “width =” 800 “height =” 480 “/>

An international team discovered a previously unrecognized ocean current that carries water to one of the world’s largest “waterfalls” in the North Atlantic Ocean: the Bank of Faroe channel overflow in the deep North Atlantic. While investigating the pathways that water takes to feed this large waterfall, the research team identified a striking path for dense, cold water flowing at depth, leading to the discovery of this new ocean current.

“This new ocean current and the path it takes to the Faroe Bank Canal are exciting findings,” said Léon Chafik, lead author of the article published in Nature’s Communications and research scientist at Stockholm University, Sweden.

“The two discoveries reported here, in one of the best-studied areas of the world ocean, are a clear reminder that we still have a lot to learn about the Nordic seas,” said co-author Thomas Rossby, professor emeritus at URI Graduate School. of oceanography. “This is crucial given the absolutely critical role they play in major glacial-interglacial climate changes.”

Previous studies of this deep flow have long assumed that these cold waters, which flow along the northern slope of the Faroe Islands, directly become the Faroe-Shetland Canal (the region through which water flows before get to the Canal del Banco Faroe). Instead, Chafik and the article’s co-authors show that there is another way to the Faroe-Shetland canal. They show that the water can take a longer path to the continental margin outside Norway before turning south in the direction of this great waterfall. “Revealing this newly identified path from available observations was not an easy process and it took us a long time to reconstruct it,” said Chafik.

The researchers also found that this new path depends on prevailing wind conditions. “It appears that atmospheric circulation plays an important role in orchestrating the identified flow regimes,” added Chafik.

The study further reveals that much of the water that will end up in the Faroe Bank Canal is not transported along the western side of the Faroe-Shetland Canal (the region through which water flows before reaching the Faroe Bank Canal) , as previously thought. Instead, most of this water comes from the eastern side of the Faroe-Shetland Channel, where it is carried by a powerful, jet-type ocean current. “This was a curious but very exciting finding, especially since we are aware that a very similar flow structure exists in the Danish Strait. We are pleased that we were able to identify this new ocean current both in observations and in a high-resolution general ocean model circulation, “Chafik said.

“Because this newly discovered flow path and ocean current play an important role in ocean circulation at higher latitudes, their discovery adds to our limited understanding of overturned circulation in the Atlantic Ocean,” said Chafik. “This discovery would not have been possible without a lot of institutional effort over the years.”