Climate change could lead to tsunamis in the Southern Ocean with human casualties – study
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Climate change could trigger giant, deadly tsunamis in the Southern Ocean. Tsunamis can be caused by underwater landslides in Antarctica. This is reported by Space with reference to a study by British scientists published in the journal Nature Communications. Scientists have discovered that during earlier periods of global warming – 3 million and 15 million years ago – sedimentary layers of rock formed and slid in Antarctica. They were the cause of huge tsunami waves that reached the shores of South America, New Zealand and Southeast Asia. Photo: I_g0rZh/Depositphotos As the oceans warm due to climate change, researchers believe there is a possibility that these tsunamis could occur again. “Underwater landslides are a serious geohazard that can trigger tsunamis that can lead to massive loss of life,” said Jenny Gales, a lecturer in the Department of Hydrography and Ocean Studies at the University of Plymouth in the UK. Researchers first found evidence of ancient landslides near Antarctica in 2017 in the eastern Ross Sea. Beneath these landslides are layers of sediment filled with fossilized marine creatures known as phytoplankton. In 2018, scientists returned to the area and drilled deep into the seabed to extract sediment cores—long, thin cylinders of Earth’s crust that reveal layer by layer the region’s geological history. So scientists learned that the sedimentary layers formed during two periods: one about 3 million years ago during the warm period of the mid-Pliocene, and the other about 15 million years ago, also during a warming climate. During these eras, the waters around Antarctica were 3 degrees warmer than today, leading to outbreaks of algal blooms that, after dying, filled the seabed with saturated and slippery sediment, leading to landslides. “During subsequent cold climates and ice ages, these slippery layers were covered by thick layers of coarse gravel carried by glaciers and icebergs,” says Robert Mackay, director of Queen Victoria University’s Antarctic Research Centre. The exact cause of past underwater landslides in the region is unknown, but researchers have identified the most likely cause: glacier melting due to climate warming. It was these landslides that led to earthquakes, which in turn caused other landslides, resulting in tsunamis. The scale and size of ancient ocean waves are unknown, but scientists note two relatively recent underwater landslides that caused huge tsunamis with human casualties. It is about the 1929 Grand Banks Tsunami, which caused waves 13 meters high and killed about 28 people off the coast of Newfoundland, Canada. And also about the tsunami in Papua New Guinea in 1998, which claimed 2,200 lives. With many layers of sediment buried under the seabed in Antarctica and glaciers on top of the land slowly melting, researchers warn that future landslides and tsunamis could happen again. We will remind, according to another study, by the year 2100 due to gradual changes in temperature and precipitation, the climate on 50% of the Earth may change significantly. Read also: NASA scientists predict an increase in floods and droughts in the world due to climate change
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