Just less than a year ago, the east coast of Greenland was hit by a megatsunami. The resulting tsunami, caused by a large landslide that entered uninhabited Dickson Fjord, was 200 meters high – the equivalent of more than 40 double-decker buses.
Fortunately, no one was injured, although a military base was wiped out. Now analysis of the seismic data associated with the event has revealed that the tsunami was followed by a standing wave, which swept back and forth in the narrow fjord for many days.
Angela Carrillo Ponce of the German Research Center for Geosciences in Potsdam, analyzed the seismic data, recorded at earthquake monitoring stations more than 3,000 miles (5,000 km) away, and found signals that persisted long after the September 16, 2023 landslide.
Using satellite imagery and computer modeling, Ponce and her colleagues were able to confirm the presence of a standing wave about 1 meter high that lasted for more than a week.
Their findings, published in The seismic recordwarns that climate change is accelerate the melting of Greenland’s glaciers and permafrost, which increases the chance of landslides and subsequent megatsunamis.
Smaller events have been observed several times in recent years, such as the rockslide in West Greenland’s Karrat Fjord in 2017, which triggered a tsunami that flooded the village of Nuugaatsiaq, destroying 11 houses and killing four people.
