Newly discovered jet stream off Iceland coast regulates climate

It’s not every day that you discover a new ocean current – especially one in the Arctic that could be impacted by climate change. But scientists at the University of Bergen in Norway, in concert with the Woods Hole Oceanographic Institute, have done just that.

Deep below the ocean surface off Iceland, Kjetil VÃ¥ge and colleagues came across what they’ve named the North Icelandic Jet, a key contributor to the Atlantic Ocean conveyor belt. This overturning of warm water from the tropics with dense, cool water from Arctic helps regulate climate along the Atlantic seaboard. It’s why Europe isn’t freezing cold, despite being at such high latitudes.

In a paper published online this week in the journal Nature Geoscience, the authors state that this newly discovered jet stream is accountable for about half the total overflow transport to the Arctic’s largest of the deep plumes — the Denmark Strait Overflow Water (DSOW), which feeds the lower limb of the Atlantic conveyor belt in the Denmark Straight between Iceland and Denmark. The newly discovered current is also the primary source of the densest overflow water.

The biggest question, as it pertains to climate change, is how the North Icelandic Jet will be impacted as more Arctic sea ice melts. How sensitive is the North Icelandic current? And what kind of determinant is it in the larger scheme of ocean water overturning?

“If a large fraction of the overflow water comes from the NIJ, then we need to re-think how quickly the warm-to-cold conversion of the [Atlantic ocean conveyor belt] occurs, as well as how this process might be altered under a warming climate,” said co-author Robert Pickart of the Woods Hole Oceanographic Institute in a press release.