A groundbreaking study suggests that climate change-induced underwater landslides in the Antarctic could unleash colossal tsunamis. Researchers have discovered evidence that past periods of global warming, millions of years ago, may have caused massive waves by triggering underwater landslides that impacted coastlines in South America, New Zealand, and Southeast Asia.
By drilling hundreds of meters beneath the Antarctic seabed, scientists uncovered sediment layers that indicate the occurrence of underwater landslides during previous climate change events. These findings lead experts to believe that as oceans heat up due to climate change, a similar phenomenon of landslides triggering tsunamis could be repeated.
The study, published in the scientific journal Nature, highlights the “unknown submarine landslide-generated tsunami risk” along Antarctica’s continental margins, which poses a threat to populations and infrastructure in the Southern Hemisphere.
While the exact cause of past underwater landslides in the region remains uncertain, scientists theorize that the melting of glacier ice in a warming climate likely played a significant role.
Amelia Shevenell, an associate professor of geological oceanography at the University of South Florida’s College of Marine Science, emphasized the potential impact of large landslides along the Antarctic margin, stating that they “have the potential to trigger tsunamis, which may result in substantial loss of life far from their origin.”
The discovery of these landslides occurred during the Italian Odyssea expedition in the eastern Ross Sea in 2017, followed by further exploration in 2018 as part of the International Ocean Discovery Programme Expedition 374. Sediment cores collected from beneath the seafloor provided insights into the climate conditions and formation of weak layers deep under the Ross Sea millions of years ago.
The study underscores the urgency of comprehending how global climate change can influence the stability of these regions and the potential for future tsunamis, according to Jenny Gales, a lecturer in hydrography and ocean exploration at the University of Plymouth.
Although the size of ancient ocean waves remains unknown, the paper highlights two historical examples of devastating tsunamis caused by submarine landslides. The 1998 Papua New Guinea tsunami unleashed 15-meter waves, resulting in the loss of 2,200 lives, while the 1929 Grand Banks tsunami generated 13-meter waves that claimed around 28 lives off the coast of Newfoundland, Canada.