Tracking ships' icy paths amid climate change

There has been much buzz about the warming planet's melting Arctic region opening shipping routes and lengthening travel seasons in ocean passageways that ice once blocked. Expanded fishing, trade and tourism is envisioned.

Operative word: Envisioned.

Scientists at Michigan State University and other institutions report in Climatic Change where vessels are traveling in the ice-covered waters of the Arctic between Alaska and Russia and what that may mean for wildlife and communities in the region.

"Even with climate change, sea ice is still a substantial barrier to Arctic vessel traffic," said Kelly Kapsar of Michigan State. "Sea ice also provides critical habitat for many endemic Arctic species and a hunting platform for Indigenous subsistence hunters. Understanding when and where ships are entering areas of sea ice can help us to better understand potential impacts of vessel traffic in the region."

Whether it's fishing vessels seeking better catches over a longer season or Russian shipping companies eager for better ways to deliver oil and gas to Chinese customers, increased marine traffic is a given. Whether this traffic occurs only in the open water season or also in times of ice cover, is not.

But the U.S. National Science Foundation-supported researchers point out the difference between what ships could do as ice changes and what they will do can be vastly different.

"Up until now projections have been about theoretical ships, such as noting certain vessel types can travel through up to 2 meters of ice," Kapsar said. "But that's like saying a car can drive up to 200 mph — just because it can doesn't mean it will."

Combining satellite pictures of ice cover with GPS vessel tracking data, the team was able to analyze how the ships have been behaving as the shipping passages change. What they've found is that many ships are following the ice, fishing close to the edge of ice packs. The researchers also found marked overlap between areas with vessels traveling in sea ice and the overwintering areas for bowhead whales.

The new analysis points to a growing threat to wildlife species using the receding ice as they travel and breed.

Noise from large boats can disrupt marine mammals. Ships equipped to break ice potentially could strand both animals and people traveling across the frozen expanses. Increased traffic also raises fear of accidents and oil spills. The new pathways are far away from rescue or clean-up crews.

So far, Kapsar said, their work indicates that ship travel reflects a certain caution, offering indications that capability is balanced by practical and economic realities. For now.