Retreating Arctic ice is opening up the northern oceans, allowing house-sized waves to thunder across the high seas, a new study reports.
Researchers from the University of Washington studied currents in the Beaufort Sea, off the coast of Alaska, in 2012 and found when the ice retreated, the surf went up.
“The wave climate is changing rapidly, and measurements from even a few years ago may not be good indicators of the conditions that can arise in future years,” says Jim Thomson, principal oceanographer at the University of Washington, by email.
Some of the largest waves the study recorded were as tall as a house. Swells of comparable size have been observed in other oceans, but the Arctic Ocean has, historically, been relatively calm and these new waves are a concerning change.
“Waves in the Arctic are reaching 5 m in height. That’s a big wave, and not something that has been measured before in the Arctic,” said Thomson.
As the Arctic ice heats up and melts in the summer the ocean grows and the waves get more space to develop and grow.
In the summer months, rather than a “seas” classification, which signifies minor surface activity, swells were developing and eventually leading to massive waves.
The study anticipates that the trends observed in the Beaufort Sea apply to the wider Arctic Ocean.
The less ice there is in the High North to either break up or contain the ocean surf, the more large waves can develop. And the more large waves there are, the more rapid the ice retreat is.
The effects could also be felt outside the Arctic.
“[There are] potentially wide-ranging implications for the air-water-ice system and the humans attempting to operate there,” the authors wrote in the study (paywall). “This would be a remarkable departure from historical conditions in the Arctic.”
The long-anticipated Arctic shipping routes and the projects planned for resource mining in the High North could be derailed by turbulent seas.
“Specifically, previous wave measurements in the Arctic would suggest that ships and structures should be designed to withstand only wind sea waves (whitecaps),” says Thomson.
“Our measurements show that ships and structures now also need to be designed to withstand swell waves.”
Allianz Global Corporate and Specialty reported in the Safety and Shipping Review 2014 that, in 2013, 94 ships were lost worldwide, with cargo ships making up a third of those. Foundering (being overcome by large waves and sunk) was listed as a major cause of the losses.
In addition, shore erosion from larger, stronger waves could jeopardize coastal communities and infrastructure.
Large waves also flush carbon dioxide into the water, temporarily removing it from the atmosphere. Though it’s not clear yet what effect this will have on marine life anything that disrupts the balance that’s existed for thousands of years will require careful observation.
“The Arctic is changing remarkably fast,” says Thomson.
“Even as a member of the scientific community, I did not fully appreciate the drastic changes that are occurring until I started studying the Arctic in detail.”