On 1st January 2024, a magnitude 7.6 earthquake hit Japan near the Noto Peninsula in the Ishikawa prefecture, prompting tsunami warnings for the nine prefectures along the west coast of the country and neighbouring areas such as South Korea.
About Tsunami
- Tsunami is a Japanese word that means “harbour wave”. It is a series of giant ocean waves caused by violent seafloor movement associated with earthquakes, landslides, lava entering the sea, seamount collapse, or meteorite impact.
- The most common cause is earthquakes. When an earthquake takes place under the ocean, a large chunk of the ocean floor can suddenly move upward or downward, leading to a sudden displacement of a large volume of water, thereby causing tsunami waves.
- Those initial tsunami waves are characterised by their long wavelength and their ability to travel underwater across the ocean at speeds that can reach up to 800km/h.
- The long wavelength means they lose very little energy. These waves are “so persistent” that they can travel across the entire Pacific Ocean basin.
- Tsunami waves can be hundreds of feet tall and can travel as fast as jet planes over deep waters while slowing down when reaching shallow waters.
- However, not all earthquakes or volcanic eruptions lead to tsunamis. The formation of a tsunami can depend on a host of factors, including the shape of the ocean floor, and the earthquake’s distance and direction.
