Science

Huge waves detected in Arctic waters for 1st time

For the first time, waves rearing as high as the second-floor windows of a building have been detected in a part of the Arctic Ocean that's normally calmed by ice.

Melting ice leaves open water, giving waves a chance to build up

Wave sensors record the height of waves. A researcher is currently on the Beaufort Sea deploying more of them. (J. Thomson/University of Washington)

Waves rearing as high as the second-floor windows of a building have been detected in the Beaufort Sea for the first time.

Arctic waves are normally kept in check by sea ice, which has traditionally covered large areas of the Arctic Ocean even in the summer. But warmer temperatures as a result of climate change are melting away more and more of that ice.

A wave gauge deployed in the Beaufort Sea in the western Arctic in 2012 has already measured some of the consequences, recording wave heights of almost five metres during a September storm.

"That's a lot bigger than anything previously recorded up there," wrote University of Washington researcher Jim Thomson in a blog post about the results.

"Of course, the ice had melted back a lot farther than anything previously recorded too."

In a new study released this week in the journal Geophysical Research Letters, Thomson and his colleague Erick Rogers at the Naval Research Lab at Stennis Space Centre in Mississippi officially reported the data collected by the wave gauge between mid-August and October 2012.

They also calculated the relationship between the available distance of open water and the size of the waves that could potentially form. As the open water between ice-covered areas increases, the wind gets more opportunity to build up waves. That means the potential size and power of the waves increase dramatically.

Those waves, in turn, may gain enough power to smash away more sea ice, generating a "feedback mechanism which drives the Arctic system toward an ice-free summer," they wrote in their paper.

In his blog post on the website of the American Geophysical Union, Thomson added, "Bigger, more powerful waves could also accelerate erosion of the Arctic Ocean coasts, which are already breaking down rapidly from the effects of climate change and melting of permafrost."

Thomson is currently out on the Beaufort Sea deploying more sensors to track how wave heights are influenced by the ice, open water and weather conditions.

The research was funded by the U.S. Office of Naval Research.