Lake Tsunamis: A Growing Threat in a Warming World

Tsunamis are not only a threat to coastal areas, but they can also occur in lakes. These lake tsunamis happen when a large volume of water suddenly changes its position. This phenomenon is becoming increasingly common in regions with mountain glaciers, such as Alaska, British Columbia, and the USA.

Lake tsunamis can be triggered by various factors, including seismic activity, landslides, avalanches, glacier ruptures, delta collapses, atmospheric changes and volcanic processes. While most lake tsunamis currently occur in remote areas with minimal impact on people and infrastructure, this could change due to climate change. As temperatures rise and glaciers and permafrost melt, the likelihood of landslides and lake tsunamis increases. For example, Portage Lake in Alaska is estimated to have a high risk of a lake tsunami.

Lake tsunamis can cause significant damage to communities and natural habitats. In 2020, a landslide in British Columbia created a 100m high tsunami that caused extensive damage. In history, lake tsunamis have resulted in fatalities and destruction. The 1938 Lake Michigan tsunami killed five people while the highest wave in history hit Alaska in 1958 at 524m tall occurred in a fjord. These events demonstrate the devastating potential of lake tsunamis.

It is essential to understand the risks associated with lake tsunamis and take necessary precautions to minimize their impact on communities and infrastructure.