The picture above shows how the shape of a tsunami wave changes as it moves into shallower water.
Click on image for full size
What Is a Tsunami?
Tsunami waves are made in an ocean or other body of water by an earthquake, landslide, volcanic eruption, or meteorite impact. Tsunamis can cause huge destruction when they hit coastlines. Some people call tsunamis "tidal waves", but these large waves really have little to do with tides, so the term "tidal wave" does not really suit them.
Tsunami waves are different from the waves you can usually find rolling into the coast of a lake or ocean. Those waves are made by wind offshore and are quite small compared with tsunami waves. Tsunami waves are huge and can travel very quickly, but they are only about one meter high in the open ocean.
As a tsunami wave travels into shallower water near the coast, it slows and grows in height. When it finally reaches the coast, a tsunami may have a height of as much as 30 meters and move much faster than a person can run. A few minutes before a tsunami wave hits, the water near shore may move away, exposing the ocean floor.
A tsunami can cause erosion at the shore and flooding inland. The water moves with such force that it is capable of crushing homes and other buildings.
Shop Windows to the Universe Science Store!
Our online store
includes issues of NESTA's quarterly journal, The Earth Scientist
, full of classroom activities on different topics in Earth and space science, as well as books
on science education!
You might also be interested in:
The ground underfoot might seem like it's not going anywhere but it is. It moves. If it moves all of a sudden the ground shakes. That's an earthquake! Earthquakes happen as pieces of the Earth's crust...more
Meteors are streaks of light, usually lasting just a few seconds, which people occasionally see in the night sky. They are sometimes called "shooting stars" or "falling stars", though they are not stars...more
1. Tsunamis that strike coastal locations in the Pacific Ocean Basin are almost always caused by earthquakes. These earthquakes might occur far away or near where you live. 2. Some tsunamis can be very...more
Earthquakes occur regularly in Sumatra, Indonesia because it is located near the boundary of two of Earth's tectonic plates. Earthquakes can create tsunamis when the seafloor moves up or down rapidly....more
Some science problems are so complicated that you need SUPERCOMPUTING power to tackle them! Just what is a supercomputer? A supercomputer is a computer that is one of the fastest or most powerful computers...more
This picture was taken from high above our planet. Looking at the Earth from very far away like this we can see that some parts of our planet look light in color, and some parts look dark. The color of...more
Did you know that many species of birds live in the desert? You have probably heard of the roadrunner or seen the cartoon. The roadrunner is a real bird that lives in the desert! It prefers to run rather...more