Breaking News: Resources for understanding, covering tsunamis

As waves begin coming ashore in Hawaii and parts of the United States touched by the Pacific Ocean prepare for a aftereffects Friday, Japan is reeling from a tsunami and earthquake there that has reportedly killed hundreds. Here is a quick guide to the basics. (See also our social media guide to people worth following for eyewitness reports and curated coverage.)

In the United States and its territories, six tsunamis have killed more than 350 people since 1946, according to the American Red Cross. In the last 204 years, 24 tsunamis have damaged the country.

FEMA says Hawaii gets one tsunami a year, and a damaging one every seven or so years. Every 18 years, California, Oregon and Washington have a damaging tsunami, according to FEMA.

How much danger does Hawaii face?
CNN reported the first wave to hit Hawaii looked like it would be about six feet, though it could be higher or lower in some places. The Weather Channel reminds viewers that subsequent waves can be much larger than the initial one.

Watch live cameras in Hawaii as events unfold:

How much danger does California face?
The L.A. Times reports that wave damage is not expected. The National Weather services says arriving waves could be three feet. However, a tsunami warning is in effect.

What is a tsunami? The National Media Tsunami Guidebook explains, a tsunami…

• is a series of ocean or sea waves caused by a sudden, large
displacement of water most often caused by earthquakes, but also by landslides, volcanic eruptions, and comet or meteorite impacts
in the ocean.
• is like a fast rising flood tide, storm surge or an advancing wall
of water and strikes with devastating force.
• may move faster than you can run.
• will continue for many hours. The first wave is often not the largest nor the most dangerous, and surges may arrive 10 hours or more after the initial wave.

You can follow the latest developments on Twitter at

Five years after the Indian Ocean Tsunami – are we better prepared and more resilient to disasters?

“The tsunami was the result of a very large undersea earthquake, where the Earth’s crust had split like a zipper along an extensive fault line, starting near Sumatra and reaching a thousand kilometres northward into the Bay of Bengal. With some shock, the public learned that geologists and seismologists were well aware of the fault and had warned that massive forces built up over hundreds of years could unleash earthquakes and tsunamis at any time.”

2005 Tsunami Coverage

Al Tompkins contributed to this report.

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