A discovery by two Icelandic oceanographers has garnered international attention because it might have significance in the context of climate change and global warming. It is a deep ocean current which flows along the continental shelf off north Iceland.
Langanes peninsula in northeast Iceland. Photo by Páll Stefánsson.
The current, which is known as the North Icelandic Jet, was first studied and described by two of the Icelandic Marine Research Institute’s specialists, Steingrímur Jónsson, who is also a professor at the University of Akureyri, and Hédinn Valdimarsson, Fréttabladid reports.
In the past few years the North Icelandic Jet has been studied further, both by Icelandic and American research vessels in collaboration between the Icelandic Marine Research Institute and Woods Hole, one of the US’s most respected marine research institutes.
On Monday Woods Hole’s research vessel Knorr headed out from Reykjavík on a month-long expedition to map the North Icelandic Jet in more detail and search for its origins.
Jónsson explained that there is a known heat-salt circulation in the ocean which has been compared to a conveyor belt. Warm seawater flows to the north where it cools and sinks.
Then a deep ocean current is formed which flows back south along the ocean floor until it eventually resurfaces and warms up again.
This circulation is to a large extent controlled by the world’s climate and the theory is that if this ocean conveyor belt is weakened the climate will cool in the northern hemisphere. Global warming is believed to be able to cause this imbalance.
The reason, in short, is the melting of the Greenland icecap. Freshwater changes the qualities of the ocean so that it becomes lighter with less salt, doesn’t sink and stops the conveyor belt.
Jónsson said the North Icelandic Jet changes this picture and with it the theory on the effect of global warming in the northern hemisphere. That is where the importance of the discovery lies and what explains the interest of US scientists.
It is considered to be possible that the North Icelandic Jet’s presence off Iceland means that the heat-salt circulation isn’t as vulnerable to the melting of the Greenland icecap.
It is also important that two deep ocean currents but not one (the East Greenland Current) are active and can reduce the impact of melting glaciers.
The origins of the North Icelandic Jet are unknown. “First we noticed it off the West Fjords but now we know that the deep ocean current can be traced all the way eastwards to Langanes. Where its ultimate origins lie is unknown, as are many other aspects. It will be our project in the coming years to complete the picture,” Jónsson concluded.
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