Northstar Island in the Beaufort Sea.

The artificial island of Northstar, an oil- and gas-production facility off the coast of Alaska, has suffered damage from high waves in the past, and would be vulnerable to the even-higher waves climate change is predicted to bring. Credit: Alamy

Ocean sciences

Extreme Arctic waves set to hit new heights

Waves crashing into Arctic coastlines could grow by as much as three metres if global warming continues unabated.

Climate change will swell the highest waves in the Arctic Ocean, endangering people who live and work in coastal areas.

As Earth warms, sea ice melts and wind patterns shift. In the Arctic, loss of sea ice allows winds to build waves higher, especially during autumn storms.

Mercè Casas-Prat and Xiaolan Wang at Environment and Climate Change Canada in Toronto used five climate models to simulate how such changes might affect Arctic waves in the last two decades of this century. They found that in an extreme future scenario in which greenhouse-gas emissions continue to soar, the maximum wave height will increase by up to 6 metres offshore and by up to 3 metres along coastlines. The biggest changes are expected in the Arctic Ocean and the Greenland Sea.

Along the Beaufort Sea’s coastline, the annual chance of damaging extreme waves will rise from the 1 in 20 chance seen towards the end of the twentieth century to between 1 in 5 and 1 in 2 by 2100. Extreme waves are a threat not only to coastal towns, but also to infrastructure, such as the Northstar oil platform in the Beaufort Sea.