1,578 feet mega-tsunami in Alaska linked to melting glaciers, and will happen again

Experts have warned that an icy mountain region in the United States could witness a disaster similar to the Nepal floods. Alaska is at risk of a climate change-induced glacial collapse, and it has actually already occurred. Alaska’s Tracy Arm fjord was struck by a "mega-tsunami" 1,578 feet high from a landslide. Scientists have now found that "the rapid retreat of a glacier set the scene for the huge slide and the following mega-tsunami."

Tourist cruise ships escaped the disaster by mere hours. Prof Bill McGuire, a climate scientist and professor emeritus at University College London, told the BBC, "It is a threat that is only going to get bigger as the planet gets hotter." He warned that people living in places under these mountain regions and tourists aboard cruise ships face a growing risk from melting glaciers.

Patrick Lynett, a professor of civil and environmental engineering at the University of Southern California, told the outlet that Alaska's mega-tsunami was linked to rapidly melting glaciers. He has warned that this was definitely not the last such event to hit the region and that they will become increasingly common. "Tracy Arm-type events will continue to happen, seemingly at an increasing rate, in fjords and other water bodies with rapidly retreating glaciers," he said.

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Rapidly melting glaciers are destabilising mountain slopes, and the warming climate is also thawing permafrost, which in turn loosens the glaciers. Permafrost is ground with rock, soil and ice that remains permanently frozen.

Earthquakes from ice loss

Ice loss in Alaska also sets the stage for earthquakes, as it removes a lot of weight from the crust below. When this happens, faults start moving and can trigger earthquakes, causing "glacier collapse and breach meltwater lakes." McGuire says any region with large amounts of ice is vulnerable going forward, and this "includes Alaska and some of the Rockies, the European Alps and – especially – the Himalayas."

Also Read: 11 trillion tons of ice has vanished from Greenland and Antarctica. That's not the worst part

Byers says to prevent "a future catastrophic event", cruise companies might have to drop the fjord from their routes. He has called for the development of "effective and locally appropriate early warning systems" to ensure timely action. However, avoiding a disaster might not be entirely possible since ships are already in motion and cannot just turn back.

What is needed is a better understanding of where hazards occur and limiting the size or number of ships in a fjord. Satellites can be used to monitor whether slopes are moving. But this may not be foolproof as well, since in heavily glaciated regions some glaciers can move several metres a day. So, in a warming world, more glacier collapses are bound to happen, and predicting them isn't easy to tell.