Tonga Shock Wave Created Tsunamis In Two Different Oceans

sciencehabit shares a report from Science.org: When Hunga Tonga-Hunga Ha'apai, a mostly submerged volcanic cauldron in the South Pacific Ocean, exploded on January 15, it unleashed a blast perhaps as powerful as the world's biggest nuclear bomb, and drove tsunami waves that crashed into Pacific shorelines. But 3 hours or so before their arrival in Japan, researchers detected the waves of another small tsunami. Even stranger, tiny tsunami waves just 10 centimeters high were detected around the same time in the Caribbean Sea, which is in an entirely different ocean basin. What was going on? Researchers say there is only one reasonable explanation: The explosion's staggeringly powerful shock wave, screaming around the world close to the speed of sound, drove tsunamis of its own in both the Pacific and Atlantic oceans. It's the first time a volcanic shock wave has been seen creating its own tsunamis, says Greg Dusek, a physical oceanographer at the National Oceanic and Atmospheric Administration who documented the phenomenon using a combination of tide and pressure gauges around the world. But, "It's almost certainly happened in the past," says Mark Boslough, a physicist at the University of New Mexico, Albuquerque. The discovery suggests the shock waves generated by explosive eruptions in Earth's history, and by other violent cataclysms, like the airbursts of comets or asteroids colliding with the planet's atmosphere, may have also created transoceanic tsunamis, perhaps with considerably bigger waves.

Read more of this story at Slashdot.