A Japanese word meaning "harbor wave." A tsunami is a wave or series of
waves that are generated in a body of water by a sudden disturbance that
displaces water. Found mainly in the Pacific, tsunami are typically caused
by earthquakes and landslides in coastal
regions. In mid-ocean, teh wave height is usually under 1 meter, the distance
between succeeding crests being of the order of 200 km, and the velocity
avout 750 km/h. Near the coast, friction with the sea bottom slows the wave,
so that the distance between crests decreases, the wave height in creasing
to about 25 meters or more.
|People run from an approaching tsunami in Hilo, Hawai'i,
on 1 April 1946; note the wave just left of the man's head in right
center of image. Credit: The Pacific Tsunami Museum in Hilo, Hawai'i
Volcanic eruptions, nuclear explosions, and even impact of meteorites, asteroids,
and comets from outer space can also generate tsunamis.
Source: U.S. Geological Survey