A tsunami is a kind of wave in the ocean. The waves of tsunami radiate out from a source area when a large volume of seawater is suddenly displaced. Causes of rapid displacement of seawater include large earthquakes that move ground, major submarine slides, exploding underwater volcanoes, and large asteroid impacts.

From a source area, tsunami radiate out across the ocean like giant ripples in a pond the size of the ocean. The ring-shaped ripples are distorted by the shape of the seafloor underneath the path of the moving waves. Tsunami can travel across entire oceans in a matter of hours.

We are most familiar with the destruction that large tsunami cause when they strike land. The crests of large tsunami can cause sea water to move far inland and take people by surprise. The energy contained in the moving water can move buildings like toys.

So what does this wave look like in the open ocean? Not much. If you were on a ship when a tsunami passed, you would not notice because the wave height would be less than 2 meters. Wind waves in the ocean would be much larger.


To think about:
If tsunami look very wimpy at sea, why do they grow into monsters close to shore? Where are they hiding all that destructive energy?


At the Ocean Institute
Visitors to the Ocean Institute generate tsunamis by simulating underwater landslides in the Institute's Tsunami Research Tank.