How Are Tsunamis Formed?

Tsunamis happen when something big and sudden pushes a lot of water all at once.

Imagine you're in a bathtub full of water, and someone jumps in, splash! The water goes flying up and out. That’s like what happens with tsunamis, but on a much bigger scale.

A tsunami starts when there's a big shake or bump under the ocean, like an earthquake or a volcano erupting. This is like someone jumping into the bathtub, it sends a wave through the water.

These waves can travel across whole oceans, sometimes for thousands of miles. They might not look very big when they’re out in the deep sea, kind of like a small ripple in the bathtub. But when they reach the shore, they get taller and faster, like when that ripple hits the side of the tub and becomes a big splash.

Sometimes tsunamis come as a series of waves, like several splashes one after another. That’s why it’s important to stay safe when you hear about a tsunami, the first wave might not be the biggest one!