A mega-tsunami caused by a landslide in Greenland caused the Earth to vibrate for nine days, a new study has shown.
The collapse of a 1.2km-high (0.7 miles) mountain peak last September caused water in the fjord below to splash back and forth, causing vibrations right through to the Earth’s crust, researchers found.
It was caused by the glacier at the foot of the mountain thinning, which was the result of climate change, according to the study, which included scientists from University College London (UCL).
The new phenomenon, which began above Dickson Fjord in east Greenland, left scientists “completely baffled”, the study’s co-author Dr Stephen Hicks said.
“This is the first time that water sloshing has been recorded as vibrations through the Earth’s crust, travelling the world over and lasting several days,” Dr Hicks, of UCL Earth Sciences, said.
“Even though we know seismometers can record a variety of sources happening on Earth’s surface, never before has such a long-lasting, globally travelling seismic wave, containing only a single frequency of oscillation, been recorded.
“Our study of this event amazingly highlights the intricate interconnections between climate change in the atmosphere, destabilisation of glacier ice in the cryosphere, movements of water bodies in the hydrosphere, and Earth’s solid crust in the lithosphere.”
To demonstrate how the water splashing continued for nine days, researchers recreated the angle of the landslide using a mathematical model.
It suggests that the water would have splashed back and forth every 90 seconds, sending vibrations through the Earth’s crust around the planet, causing one of the largest tsunamis in recent history.
The wave extended 10km (7.4 miles) across the fjord and 110m into the air – but reduced to 7m within minutes, the study, published in the journal Science, estimates.