Out of the shock and disbelief brought by the earthquake and tsunami disaster in Japan, many people are rightly asking can a tsunami strike the United States? The answer is: yes and it already has.
Tsunamis are typically generated by earthquakes of magnitude 7.0 or greater when they occur at a shallow enough depth under the ocean. The 9.0 earthquake that struck Japan was 100 times stronger than a 7.0 — and the United States is not immune from a quake of that intensity.
On March 28, 1964, the Great Alaska earthquake — measuring 9.2, the second strongest earthquake recorded — resulted in a tsunami that claimed 124 lives and caused $84 million in damage from Alaska to California. Since 1964, populations along these coastlines have increased — posing a greater risk for loss of life and economic impact. And as recently as September 2009, 34 people were killed in American Samoa, when the island was struck by the dual disaster of an earthquake measuring 8.1 and the tsunami that followed.
The tsunami that devastated Indonesia in December 2004 was a wakeup call for the United States.
At the time, the United States had a mere six tsunami-detecting buoys in the eastern Pacific Ocean. Now, a network of 39 buoys encircles the Pacific and strategically monitors the western Atlantic, Gulf of Mexico and Caribbean. Specialized forecasters armed with advanced modeling are staffing centers around-the-clock and are issuing tsunami alerts within minutes of an earthquake and providing coastal residents with as much advance notice as possible.
Our increasingly sophisticated means of observing and warning for tsunamis is vital but warrants ongoing investment. And this warning process is not complete or effective without an educated public that knows how to take appropriate action. As with all hazards, whether natural or man-made, it is critical that we all take steps to know and understand our risks, and the simple actions we can take in the event they occur.
While anyone living along a coastline should be prepared for a tsunami, the risks posed by earthquakes aren’t exclusive to these areas — earthquake activity has been felt in all 50 states. In fact, two hundred years ago the New Madrid earthquakes, a series of intense earthquakes, struck states in the central United States, but were felt as far away as the District of Columbia, Boston and Maine. And according to USGS, history could soon repeat itself — they predict another major earthquake could strike this same region in the next 50 years.
The bottom line — all of us, no matter where we live, should take steps now to be prepared for earthquakes, tsunamis and other hazards. It starts with a plan: Know where to go in the event of an earthquake and tsunami and how you would communicate with your family, friends or co-workers if a disaster struck. Put together an emergency supply kit for your home, office or car with essential items you would need in an emergency, from first-aid items to important personal documents.
And be informed about what to do to protect yourself in the immediate moments after a tsunami, earthquake or another disaster strikes. Visit www.ready.gov to learn more.
Our thoughts and prayers remain with the people of Japan as they continue to recover from this horrific tragedy. What they are going through is an urgent reminder to all of us that disasters can strike anytime, anywhere. We cannot stop the next great earthquake or the tsunami that may come with it, but families and individuals must be prepared to recognize the danger and take the steps now to prepare — before the next disaster strikes.
Warning signs of a tsunami:
• A strong earthquake, or one that persists for 20 seconds or longer
• The ocean withdraws or rises rapidly
• A loud, roaring sound (like an airplane or a train) coming from the ocean
• Tsunami warnings broadcast over television and radio, by beach lifeguards, community sirens, text message alerts, National Weather Service tsunami warning center websites and on NOAA Weather Radio All Hazards
What you should do if you see these signs:
• Keep calm
• Immediately move to your local tsunami shelter using defined tsunami evacuation routes
• If there are no evacuation routes defined, move to higher ground that is at least 100 feet in elevation, a mile inland, or to the highest floor of a sturdy building and STAY there.
• If you are already in a safe location, STAY there
• Move on foot when possible — do not drive — keep roads clear for emergency vehicles
• Stay tuned to NOAA Weather Radio or news broadcasts for changes in tsunami
• Hayes is the director of NOAA’s National Weather Service. Fugate is the administrator of the Federal Emergency Management Agency.