A Warning from the Ice: Alaska’s Growing Megatsunami Risk

A massive wave, known as a megatsunami, recently struck a remote fjord in southeast Alaska, serving as a powerful warning about the dangers of a changing climate. According to The Guardian, the event took place last August in the Tracy Arm fjord. A giant landslide caused 64 million cubic meters of rock to fall into the water. This created a wave that reached 481 meters in height. To understand the scale of this, the Eiffel Tower is only 330 meters tall. Research published in the journal Science noted that this was the second-tallest tsunami ever recorded in history.

Experts explain that this disaster was largely caused by the melting of glaciers. As the climate warms, glaciers retreat, or move back, leaving steep cliffs without support. Dr. Stephen Hicks from University College London explained to the BBC that the ice was previously helping to hold up the rock. When the ice disappeared, it exposed the bottom of the cliff, which allowed the rock to suddenly collapse into the water. Researchers believe that without this rapid glacier retreat, the landslide might not have happened at all.

Fortunately, the timing of the event prevented a tragedy. The landslide occurred at 5:26 a.m. local time, when no cruise ships were directly in the path of the wave. However, the area is a very popular destination for tourism. The Guardian reports that approximately three cruise ships pass through the fjord every day. In fact, two large cruise ships had visited the area just the day before, and another was scheduled to arrive the following day. Dr. Bretwood Higman, an Alaskan geologist who visited the site, described the event as a "close call" and expressed fear that future events might not be as lucky.

This incident highlights a growing conflict between the desire to see natural wonders and the increasing risks of climate change. Many tourists travel to Alaska specifically to learn about the environment and see glaciers before they disappear. However, scientists are worried that these remote areas are becoming much more dangerous. Dr. Higman noted that the risk of these megatsunamis is increasing significantly, potentially becoming ten times more frequent than they were just a few decades ago. Because of these safety concerns, some cruise companies have already announced that they will stop sending ships into the Tracy Arm area.

Unlike tsunamis caused by earthquakes in the open ocean, which can travel thousands of miles, these landslide-generated waves are usually localized. This means they happen in a specific, smaller area. However, they are often much taller and more powerful when they first hit the water. The Tracy Arm event was so strong that it created a 36-hour seiche, which is a standing wave that moves back and forth within a closed body of water. It also produced seismic waves similar to those of a 5.4 magnitude earthquake.

Eyewitness accounts show just how far the effects of such a wave can reach. A group of kayakers camping 55 kilometers away reported that the water surged past their tent and swept away their gear. Another observer on a boat 50 kilometers away saw waves cresting along the shoreline. These reports confirm that even those who are not directly at the site of the landslide can still face danger.

In response to these findings, scientists are calling for wider monitoring of hazards in parts of Alaska that are vulnerable to landslides. As the climate continues to change, the landscape of Alaska will keep shifting, making it difficult to predict where the next collapse might occur. For now, the scientific community is urging caution, reminding both tour operators and travelers that the natural beauty of these fjords comes with hidden, and increasingly serious, risks.