Tsunami

A tsunami is a series of waves generated when a body of water, such as an ocean is rapidly displaced on a massive scale. Earthquakes, mass movements above or below water, volcanic eruptions and large meteorite impacts all have the potential to generate a tsunami. The effects of a tsunami can range from unnoticeable to devastating.

The term tsunami comes from the Japanese language meaning harbour and wave. Although in Japanese tsunami is used for both the singular and plural, in English tsunamis is well-set as the plural. The term was created by fishermen who returned to port to find the area surrounding their harbour devastated, although they had not been aware of any wave in the open water. A tsunami is not a sub-surface event in the deep ocean; it simply has much smaller amplitude offshore, and a very long wavelength, which is why they generally pass, unnoticed at sea, forming only a passing "hump" in the ocean.