- A devastating tsunami is hitting a remote tourist and tourist destination, which is home to fishing villages.
- A rock wall visible with a glacier is crumbling about to collapse into the waters below.
- Glaciers hold such areas together – and when they are gone, bad stuff can be left behind.
Glacier Barry gives its name to Barry Army Fjord in Alaska, and a new open letter predicts the trouble ahead.
Thanks to global warming, the glacier has returned, so far removing two-thirds of the support for a mile-long steep slope, or scarf, containing perhaps 500 million cubic meters of material. . (Consider the Hoover Dam several hundred.) The slope has been moving slowly since 1957, but scientists say it has grown into an avalanche waiting to happen, perhaps within the next year, and possibly within 20. When it comes to falling down to the fjord, it could trigger a terrifying tsunami crossing the peaceful waters of the fjord.
“It could happen at any time, but the danger just goes up as this glacier passes,” said Woods Hole hydrologist Anna Liljedahl, one of the signatories. to the letter.
Fjord Arm Barry
Camping on the black sandy beach of the fjord
Image source: Matt Zimmerman
The Barry Arm Fjord is a stretch of water between the Harriman Fjord and the Port Wills Fjord, located at the northwest corner of the famous Prince William Strait. It is a beautiful area, with a few hundred people supporting the local fishing industry, and is also a popular tourist destination – Sand Beach is one of the most popular. Alaska’s most beautiful scenery – and cruises.
It’s not Alaska’s first aquatic rodeo, but probably the largest
Image source: whrc.org
There have been at least two similar incidents in the history of the state recently, though they were not to such a great extent. On July 9, 1958, a nearby earthquake caused 40 million cubic yards of rock to slide suddenly 2,000 feet down into Lituya Bay, triggering a tsunami with high waves. reached 1,720 feet in height. By the time the water wall reached the mouth of the bay, it was still 75 feet high. At Taan Fjord in 2015, a landslide caused a tsunami erupting at 600 feet. Fortunately, both of these incidents occurred in sparsely populated areas, so not many people died.
The Barry Arm event will be largely larger than either of those.
“This is a huge slope – the potential weight is over a billion tons,” said geologist Dave Petley, speaking to Earther. “The internal structure of that rock, which will determine whether it falls apart, is very complex. At this stage we don’t know enough about it to be able to predict it. to carry in the future. “
Outside Alaska, off the west coast of Greenland, a 300-foot-high landslide tsunami devastated a fishing village in its path.
What the letter foretells for Barry Arm Fjord
Moving slowly at first …
Image source: whrc.org
“The effects would be particularly severe near where the landslide enters the water at the head of Barry’s Army. In addition, there would be areas of shallow water, or low-lying land nearby. the shoreline, in danger even further from the source, may not exert a significant external impact on parts inside the timber, and complete failure could be devastating throughout Barry Arm, Harriman Fiord, and parts of Port Wells. Our first results show complex effects further from the landslide than the Barry Arm, with over 30 foot waves in some remote bays, including Whittier. “
The discovery of the obstructed landslide began with a study by the sister of geologist Hig Higman of Ground Truth, a group in Seldovia, Alaska. Artist Valisa Higman was on holiday in the area and sent her brother pictures of disturbing fractures she noticed in the slope, which was taken while she was on a boat traveling on the fjord.
Higman confirmed his sister’s hunt through the available satellite images and, digging deeper, discovered that the slope had shifted 600 feet down a slope between 2009 and 2015, leaving a visible scarf.
Chunli Dai at Ohio State found a link between the movement and the decline of the Barry Glacier. Comparing Barry Arm’s slope with other similar areas, along with possible computer modeling of the resulting tsunamis, the group’s letter was published.
Although the full body of signatories from 14 organizations and institutions have only been working on the situation for a month, the effects were immediately clear. Signage includes experts from Ohio State University, University of Southern California, and the University of Alaska’s Anchorage and Fairbanks campuses.
Once they were informed of the contents of the open letter, the Alaska Department of Natural Resources immediately issued a warning that “a landslide-like landslide could have devastating effects. fishermen and recreationalists. “
How do you prepare for something like this?
Image source: whrc.org
The obvious question is what can be done to prepare for a landslide and tsunami? For one thing, there is more to understand about the upcoming event, and the researchers explain their plan in the letter:
“To inform and update risk mitigation efforts, we would like to follow a number of lines of study: Identifying changes in the slope of a potential landslide forecast, gaining a better understanding of the potential for landslides. slope, and updated tsunami model projections. By mapping a landslide and nearby land, both above and below sea level, we can accurately measure the underlying physical dimensions of the landslide. This can be paired with GPS and seismic measurements made over time to see how the slope responds to changes in the glacier and to events such as rainstorms and earthquakes. Field and satellite data can support near real-time risk analysis, and computer models of landslide and tsunami scenarios can help identify specific areas most at risk. “
In the letter, the authors reached out to those who live and visit the area, asking, “What specific questions are more important to you?” And “What could be done? to reduce the risk to people who want to visit or work in Barry Arm? ” They also invited locals to tell them about any changes, including even small rock waterfalls and landslides.