The world is underestimating the geological consequences of global warming, which could trigger catastrophic earthquakes and tsunamis as the melting of ice sheets reduces the weight on the crust below and unleashes intense seismic activity, a leading earth scientist has warned.
The biggest threat in the north Atlantic comes from the thinning of Greenland’s ice cap, Bill McGuire, professor of earth sciences at University College London, told the British Science Festival in the UK town of Chelmsford on Thursday. Within decades, that could spark huge submarine earthquakes off the coast of Greenland, causing tsunamis with disastrous consequences for North America and probably Europe, he said.
A possible precedent was the “great Storegga tsunami” that devastated the coasts of Scandinavia and the British Isles 8,200 years ago. An offshore earthquake, triggered by the release of pressure after northern Europe’s ice sheets had melted, set off a vast landslide of submarine sediments under the Norwegian Sea. Geological evidence shows the resulting tsunami wave reached 15 to 20 metres high in the Shetland islands and 3 to 6 metres high further down the North Sea.