In September 2023, a colossal landslide in Greenland’s Dickson Fjord triggered a megatsunami, causing the entire planet to vibrate every 90 seconds for nine days. An unprecedented seismic hum was detected worldwide. Satellites have now unveiled the cause: resonant fjord oscillations.

A 25.5 million cubic metre rockslide, driven by climate change-induced glacial melt, plunged into the 540-metre-deep fjord, spawning a 200-metre tsunami wave. This initiated prolonged water sloshing, akin to a vast bathtub, with the fjord’s narrow confines amplifying the effect.
Credit: National Geographic