A massive landslide in Greenland's Dickson Fjord has been confirmed as the source of enigmatic tremors that reverberated globally for nine days last September. The seismic disturbances, initially baffling to scientists, were linked to a towering tsunami triggered by the collapse of a mountainside.
The Tsunami Event
The landslide, involving approximately 25 million cubic meters of rock—equivalent to the volume of 25 Empire State Buildings—plunged into the fjord, generating a 200-meter high wave. This wave became confined within the narrow fjord, leading to oscillations that produced persistent seismic signals detectable worldwide.
Scientific Investigation
The breakthrough came through an international effort involving scientists from UCL and the Danish Navy. Dr. Stephen Hicks of UCL described the initial seismic signal as an “unidentified seismic object,” distinctly different from typical earthquake patterns. This signal persisted every 90 seconds over the nine-day period.
Through detailed analysis of seismic data, satellite imagery, and pre- and post-event photographs, researchers pinpointed the landslide’s origin in Dickson Fjord. Visual evidence showed a significant dust cloud and alterations to the glacier’s surface, verifying the landslide’s impact.
Climate Change Connection
Published in Science, the research links the landslide to climate change. Warming temperatures in Greenland have weakened glaciers that support mountain structures, leading to more frequent landslides. Dr. Hicks highlighted that “the glacier was supporting this mountain, and as it thinned, it stopped holding it up.” The ongoing climate crisis appears to be exacerbating the risk of such dramatic events.
Implications and Future Research
Though the event occurred in a remote region, it raises concerns for Arctic areas where similar incidents may become more common. Dr. Kristian Svennevig from the National Geological Surveys for Denmark and Greenland (GEUS) stressed the importance of further research to understand and address these phenomena.
Dr. Hicks noted that this event could represent “the first time a climate change event has impacted the crust beneath our feet all the world over,” highlighting the broader implications of climate-induced geological changes.