Among the most mysterious disasters, tsunamis–Japanese for “harbor waves”–claimed over 50,000 lives in the 20th century! Generated by offshore earthquakes, volcanic eruptions, and landslides, these giant water walls result from large-scale displacement of seabed sediment. Rolling rapidly over the ocean floor, a tsunami rises to rapturous heights when it hits land. Scientists in Japan, Hawaii, Oregon, Washington, and California show the latest technology used to predict these killer waves.