What is a Tsunami?
Tsunami is a Japanese word meaning "harbor wave". They are ocean waves that occur due to an earthquake on the ocean floor. Tsunami waves have small wave heights and long wavelengths, so they usually go unnoticed at sea. When traveling up the slope to a shoreline, the wave is pushed upward. The speed of the bottom of the wave is slowed by friction. This causes the wavelength to decrease and the wave to become unstable. These factors create an enormous and deadly wave.