What is a tsunami? Unable to view our graphics? Click here to see them. Tsunamis are a series of giant waves caused by undersea earthquakes at tectonic plate boundaries, or volcanic eruptions.

One of this century’s most powerful earthquakes struck off the coast of Russia and generated tsunami warnings and advisories for a broad section of the Pacific, including Alaska, Hawaii and the ...

Tsunami advisories, including some warnings, were in place for the state, where officials reported waves also struck the coast. As of 7:30 a.m. PT on July 30, no major damage had been reported in ...