A team of climate scientists who wrote an open letter to the Alaska Department of Natural Resources (ADNR) announcing their concerns about about an area called Prince William Sound along the south coast of Alaska. In particular, the Barry Glacier. Satellite images have shown how ice melt on the glacier has left a large rocky area exposed. It means that there has been a slow erosion of the mountain that could be the start of a major collapse into the ocean.
The scientists wrote: “We, a group of scientists with expertise in climate change, landslides, and tsunami hazards, have identified an unstable mountain slope above the toe of Barry Glacier in Barry Arm, 60 miles east of Anchorage, that has the potential to fail and generate a tsunami.
“This tsunami could impact areas frequented by tourists, fishing vessels, and hunters (potentially hundreds of people at one time).
“We believe that it is possible that this landslide-generated tsunami will happen within the next year, and likely within 20 years.”
Prince William Sound is a remote area but its surrounding waters are often frequented by boats, including cruise ships.
“In Taan Fiord (Icy Bay, Alaska), a landslide that began moving slowly decades ago suddenly failed in October 2015.
“The resulting tsunami reached elevations of 633 feet near the landslide, and 35 feet 15 miles away.
“At Karrat Fiord, west Greenland, a landslide in June 2017 similarly produced a tsunami that killed four people and destroyed a large portion of the town of Nuugaatsiaq, 20 miles away.
“Surviving villagers still have not returned because a nearby slope is deforming and threatening to fail.
“The unstable slope in Barry Arm is much bigger than either of these examples, and thus has the potential to produce a larger tsunami that could have impacts throughout Prince William Sound.”
A previous landslide in 1958 that struck the region resulted in the tallest tsunami wave in modern times. Some reports recorded the height of the wave reaching 1,720 feet tall and was described as looking like an atom bomb by eyewitnesses.
Geophysicist Chunli Dai from the Ohio State University told NASA’s Earth Observatory: “It was hard to believe the numbers at first.
“Based on the elevation of the deposit above the water, the volume of land that was slipping, and the angle of the slope, we calculated that a collapse would release 16 times more debris and 11 times more energy than Alaska’s 1958 Lituya Bay landslide and mega-tsunami.”
For now, the scientists plan to continue observing the landslides on the glacier, in order to create a pre-warning that could save lives of people living as close as ten miles away.