Greenland landslide unleashes 650-foot mega-tsunami, triggering nine days of global seismic ripples

On Sept. 16, 2023, more than 25 million cubic yards of rock and ice plunged into Greenland’s Dickson Fjord, spawning a 650‑foot mega-tsunami that set off a sustained seismic signal heard around the world for about nine days. The waves produced a regular seiche with measurable surface oscillations, and scientists traced the event to the fjord’s geometry and a landslide, while noting climate-driven glacier retreat as a contributing factor. Using satellite imagery, field observations, and computer models, researchers reconstructed the sequence and highlighted the potential for improved Arctic warning systems as next-generation satellites like SWOT expand monitoring capabilities. The full study appeared in Science and Nature Communications.