Sea-ice loss could cause extreme Arctic waves, study says

The devastating impacts of climate change on coastal communities in the Arctic, where homes are at risk of falling into the sea due to eroding shorelines, have been well documented. New research now says “extreme” waves could be an issue in places like Tuktoyaktuk.

A study published in the journal Geophysical Research Letters argues that as sea ice continues to melt – exposing more water to stronger winds – waves will get significantly higher. This will affect ecosystems and wildlife, the study suggests, causing more flooding and damage to coastal infrastructure.

“The changes in the Arctic, and particularly waves, are going to be large, and these can have a huge impact in communities on infrastructure, also possibly shipping routes,” said Mercè Casas-Prat, a research scientist with Environment and Climate Change Canada and the study’s lead author. 

“The North is one of the areas which is a hotspot for climate change,” she said. “So there was a lot of interest in knowing how the climate there is going to change and in particular how waves can change in the future, due to sea-ice retreats and the opening of the water.”

The study projects waves could increase by as much as two metres above current levels near the shoreline by the end of the century. Extreme wave events that used to happen only once every 20 years could also start happening every two to five years. 

Casas-Prat said researchers used five climate models to look at potential wave increases in the Arctic between two periods: 1979 to 2005 and 2081 to 2100. They found a “notable” increase in wave height between the two periods in almost every place in the Arctic – particularly in the Greenland Sea, where maximum annual wave heights could increase by as much as six metres. 

“It is not going to be a sudden increase, it is going to be gradual,” Casas-Prat said.

Asked if anything could be done to reduce or prevent those changes, she noted the study does consider a scenario where greenhouse gas emissions are reduced. 

“We can always do something to reduce it, but we need to be ready that it is going to be increasing very likely in that area,” she said. 

The study notes it’s important to assess how wave heights could change in order to plan for future risks like oil spills as more Arctic shipping routes open up.

Casas-Prat said additional studies need to be done to confirm the timing of when these changes are likely to happen.