Huge tsunami from Greenland shook land for nine days in 2023, study finds

A tsunami caused by a landslide in a Greenland fjord caused by climate change shook the Earth for nine days in September 2023, an international team of researchers revealed in the journal Science Thursday September 12. “What is quite unique about this event is the duration of the seismic signal and the constancy of its frequency,” explained to AFP one of the authors of the study, Kristian Svennevig, from the National Geological Survey of Denmark and Greenland (Geus).

In September 2023, 25 million m2 of rock and ice fell into this remote and uninhabited fjord, nearly 200 km from the ocean. The landslide triggered a 200-metre-high mega-tsunami at its epicenter, destroying cultural and archaeological heritage. 70 km away, four-metre-high tsunami waves damaged a research base on the island of Ella.

The collapse was caused by the thinning of the glacier at the base of the mountain, itself created by climate change, Geus explained. “With the Arctic continuing to warm, the frequency and magnitude of these events can be expected to increase in the future,” warned Kristian Svennevig, stressing that he had not “no experience of an Arctic as warm as the one we are currently observing”. It calls for the establishment of early warning systems, a challenge in these extreme environments.