the deadly force

16 JUNE 2008

Though it's true that tsunamis are ocean waves, calling them by the same name as the ordinary wind-driven variety is a bit like referring to firecrackers and atomic warheads both as "explosives." Triggered by volcanic eruptions, landslides, earthquakes, and even impacts by asteroids or comets, a tsunami represents a vast volume of seawater in motion -- the source of its destructive power.

The Japanese characters for tsunami mean "harbor wave," and many people commonly refer to them as tidal waves, but in reality tsunamis have little to do with tides. They are creatures of the open ocean, trains of giant waves that can travel for thousands of miles across the sea and still pack enough energy to smash towns and drown the unwary.

A tsunami generated in the Aleutian Islands struck Hawaii in 1946.