A recent study reveals that a massive landslide in an Alaskan fiord triggered one of the largest tsunamis in history, with a towering wave reaching 481 meters, taller than the CN Tower’s highest viewing platform. The study’s lead author, Dan Shugar from the University of Calgary, emphasizes the need for policymakers to prioritize the risk posed by such catastrophic waves, especially in British Columbia.
The research, published in Science journal, highlights that the tsunami near the Alaska-B.C. border was a result of a glacier’s rapid retreat that cleared the path for the landslide. The study warns that as global warming continues and infrastructure expands, the threat of fiord tsunamis triggered by landslides is escalating, potentially leading to future disasters.
The landslide, which occurred in Tracy Arm Fjord, involved over 64 million cubic meters of rock falling a kilometer into the narrow fiord, creating a wave with the second-highest run-up ever recorded. Fortunately, the cruise ship present in the fiord at the time was not in the tsunami’s trajectory, averting a potential maritime catastrophe.
Researchers noted that the South Sawyer Glacier’s retreat of 500 meters in the months preceding the incident played a crucial role in the landslide. They attribute the glacier’s retreat and the subsequent landslide to human-induced warming, which has caused glaciers to thin and recede.
Despite the risks posed by such events, experts like Shugar believe that precautionary measures, such as early warning systems, should be implemented rather than restricting cruise ship and tanker activities in Canadian waters. The study underscores the importance of assessing slope hazards and investing in monitoring technologies to mitigate future risks. Efforts are underway to study fiord hazards by the Geological Survey of Canada, urging policymakers to address this issue at a national level.
