Climate change triggered landslide and sent seismic shocks across the Earth for 9 days, study says

New Delhi: A landslide in Greenland triggered by melting glaciers due to climate change caused an earthquake whose tremors were heard across the planet for nine days and damaged infrastructure, a new study says.

In September 2023, a 1.2-kilometer-high mountain peak collapsed in a fjord in East Greenland – a narrow bay between two steep cliffs – and triggered a tsunami about 200 meters high.

Researchers reported that the giant wave rocked back and forth across the fjord for nine days, sending seismic tremors throughout the Earth's crust that puzzled scientists around the world.

Although no one was injured, the tremors destroyed infrastructure worth almost $200,000 at an unoccupied research station on the island of Ella in East Greenland, said the international team, which also included researchers from University College London (UK).

In their view, the landslide was a result of the melting of the glacier at the foot of the mountain, which became thinner and was no longer able to support the rock face above it – which was ultimately due to climate change.

“Our findings underscore how climate change is causing cascading, dangerous feedbacks between the cryosphere, hydrosphere and lithosphere,” the authors wrote in the study, published in the journal Science.

“When I first saw the seismic signal, I was completely baffled. Although we know that seismometers can record a variety of sources on the Earth's surface, never before has such a long-lasting, globally propagating seismic wave been recorded containing only a single frequency of vibration. This inspired me to lead a large team of scientists to solve the mystery,” said co-author Stephen Hicks of University College London.

For the study, researchers used a mathematical model and recreated the landslide and the uniquely narrow and winding fjord to understand how the sloshing of water could continue for nine days without abating.

The team, consisting of 68 scientists from 41 research institutions, combined seismic recordings from around the world, field measurements, satellite images and computer simulations for its analysis.

Ultimately, the simulations succeeded in accurately reproducing both the height of a real tsunami and the slow cycles of the long-lasting back and forth sloshing of the water, it was said.

By combining different data sets, the model predicted that the giant tsunami wave would have moved back and forth every 90 seconds, consistent with records of vibrations propagating in the Earth's crust around the globe, the researchers said.

As the Earth's polar regions continue to melt due to climate change, there could be an increase in large, destructive landslides like this one, it said.

“Climate change is changing what is normal on Earth and can trigger unusual events,” said co-author and seismologist Alice Gabriel of the Scripps Institution of Oceanography at the University of California, San Diego, USA.