On Sunday morning, landslides in the Endicott Arm area of Alaska, close to Juneau, triggered a local tsunami with waves reaching heights of about 15 feet.
The Alaska Earthquake Center received reports from boats in the Endicott Arm about this unexpected tsunami near Harbour Island.
Three kayakers who were camping on Harbour Island lost most of their equipment but made it back safely to Juneau, as confirmed by the earthquake center.
Waves near Harbour Island were estimated to be between 10 and 15 feet tall.
The National Park Service indicated that a tsunami caused significant erosion, with trees being uprooted from the steep slopes of Sawyer Island.
Ezgi Karasözen, a research scientist at the Earthquake Center, noted that no earthquakes were recorded in the vicinity that could explain the tsunami, and the area fell outside their landslide detection range.
Using the center’s landslide characterization algorithm, Karasözen analyzed data from local seismic stations and concluded that a large-scale landslide was responsible for the tsunami.
“Our initial estimates suggest the landslide was near the South Sawyer Glacier, involving possibly over 100 million cubic meters of material,” said Karasözen.
The Alaska Earthquake Center stated this might be the most significant landslide and tsunami occurrence in Alaska since 2015.
This event was detected by a seismic station more than 600 miles away.
The US Coast Guard conducted aerial surveys of the landslide locations near South Sawyer Glacier and Tracy Armfjord.
Footage revealed debris scattered on the ground, showcasing visible paths of destruction on the mountainside.
According to the Earthquake Center, several small earthquakes preceded the landslides by a few hours.
It is estimated that these minor tremors were occurring for over 18 hours before the landslide event took place.
Juneau’s National Weather Service confirmed that there were no injuries or structural damage resulting from the landslides or the tsunami.
In a related concern, Juneau is preparing for potential flooding from a glacial lake linked to the Mendenhall Glacier, prompting evacuations as a precautionary measure.
