'Height of 200-meters': Greenland's 2023 tsunami waves detected 5,000 km away from mainland

Produced by: Tarun Mishra

Massive Landslide Triggers Mega Tsunami

In September 2023, a significant landslide in eastern Greenland resulted in a mega tsunami, captivating the global scientific community. The event, which occurred on September 16, led to enormous waves in the remote Dickson Fjord.

Study Reveals  Seismic Impact

A new study published in the Seismic Record by researchers from the GFZ German Research Centre for Geoscience, led by Angela Carrillo-Ponce, identified two seismic signals from the landslide. The first was a high-energy signal from the rockslide itself, which generated the tsunami.

Persistent Very Long-Period Wave Detected

The second seismic signal, a very long-period (VLP) wave, persisted for over a week. This signal, detected as far as 5,000 kilometers away, indicated the formation of a seiche—a standing wave that oscillated within the Dickson Fjord for days.

Megatsunami's Scale  and Impact

The tsunami caused by the landslide was massive, with run-up heights exceeding 200 meters near the entry point and averaging 60 meters along a 10-kilometer stretch of the fjord. While the event occurred in a remote location, it severely damaged a military base on Ella Island, though no casualties were reported.

Increasing Risks Linked to Climate Change

This event highlights the growing risk of such phenomena in Greenland and other similar regions, where climate change is destabilizing rocky slopes and glaciers. The study draws comparisons to previous incidents, like the 2017 Karrat Fjord tsunami, which had devastating consequences.

Significance of Global Detection

Carrillo-Ponce emphasized the significance of the findings, noting that the ability to detect the signal of a rockslide-triggered wave in a remote area of Greenland on a global scale, and for an extended period, is a notable achievement in geoscience.

Credit: Georgia Institute of Technology

Future Monitoring  and Research

The study's approach, combining seismic analysis with satellite imagery, offers valuable insights for future monitoring of similar events. As climate change continues to reshape polar landscapes, understanding and predicting such catastrophic events becomes increasingly crucial for protecting coastal communities and advancing geoscientific research.