Alaska Tsunami Threat Could Spell Trouble
Scientists sounded the alarm bells in May 2020 regarding the risk of a massive Alaska tsunami occurring, spurred by the increased probability of a landslide in the Alaskan fjord known as Barry Arm. If this happens, the impact could be catastrophic. Not surprisingly, the increased risk is driven by climate change.
Nuts and Bolts of the Alaska Tsunami Threat
The crux of the problem lies in a glacier that helps support parts of this very steep fjord. Warming temperatures have eroded the ice and permafrost that forms this supportive glacier, and it now only supports less than half of the fjord. This means that any damaging weather event in the area, such as an earthquake or a long period of torrential downpours, could trigger a landslide that in turn creates a massive tsunami. And unfortunately, Alaska is among the most earthquake-prone areas on Earth.
Although this glacial erosion has been occurring for decades, it has accelerated in recent years to the point where a landslide-triggered Alaska tsunami is possible within a year, and probable within the next 20 years. In fact, scientists had only been studying Barry Arm for 4 weeks before determining that it would be wise to inform people about this growing risk.
Bottom line is that it seems like it’s a matter of when, not if, this will happen. The slope of Barry Arm consists of approximately 500 million cubic meters of dirt and rock, and computer simulations show that a full collapse would create a tsunami of unprecedented proportions.
To put this in perspective, the most well-known tsunami-inducing landslide in Alaska occurred in Lituya Bay in 1958, which reached a height of 1,720 feet and involved approximately 36 million cubic meters of dirt and rock (or, about 7% of what the Barry Arm would produce).
Most of you, like me, are not anywhere close to Alaska, so there probably would not be any direct impact on us. That said, this impending Alaska Tsunami is yet another sign that the warming climate is making our jobs as emergency preparedness professionals more complex – and more necessary – than ever before.
