Tsunami alert in Japan, Philippines: “3 feet or above waves,” warns U.S. Tsunami Warning System – Times of India

The tsunami is expected to hit the southern Philippines and parts of Indonesia, Palau and Malaysia.

What is a tsunami? Why does it occur?

A tsunami is a series of ocean waves with extremely long wavelengths and high energy, typically caused by large-scale disturbances in the ocean, such as underwater earthquakes, volcanic eruptions, or landslides. The word “tsunami” is Japanese, meaning “harbor wave,” reflecting the phenomenon’s ability to cause devastating impacts when reaching coastal areas.

Most commonly, tsunamis are triggered by the vertical movement of tectonic plates beneath the Earth’s surface. When these plates suddenly shift, they can displace a significant volume of water, generating powerful waves. Earthquakes along subduction zones, where one tectonic plate is forced beneath another, are particularly potent tsunami sources. The sudden uplift or subsidence of the seafloor displaces the water above it, initiating the formation of tsunami waves.

As the waves travel across the open ocean, their long wavelengths make them less noticeable. However, as they approach shallower coastal waters, their energy compresses, causing the waves to grow in height and potentially resulting in destructive flooding upon reaching the shore. Tsunamis can pose significant threats to coastal communities, emphasizing the importance of early warning systems and preparedness measures to mitigate their impact.