Narrator: This is Science Today. Tsunami is a Japanese word that means "harbor wave". Casey Moore, a professor of Earth Sciences at the University of California, Santa Cruz says tsunamis - which are sometimes called tidal waves - are caused by earthquakes, underwater landslides, volcanic eruptions or impact from meteorites.
Moore: In any case, if it's a landslide or a tectonic earthquake-related movement, the water surface gets disturbed and that wave moves out and propagates.
Narrator: Although tsunamis are not very frequent, when they do occur, they tend to be quite notable since they can travel long distances.
Moore: For instance, the earthquake in 1964 in Alaska - the tsunami devastated Eureka, California. It came because of the ocean bottom and the wave came in and focused there and there was a substantial amount of damage.
Narrator: Moore is part of an international research team that's working to improve risk assessment of catastrophic earthquakes, which can trigger tsunamis. For Science Today, I'm Larissa Branin.