CCU scientist: Tsunami threat exists on East Coast

A tsunami swirls in the Pacific Ocean. / Courtesy: AP Photo

A tsunami is a series of seismic sea waves produced by some kind of displacement of the sea floor, usually occuring in an earthquake zone, says Dr. Paul Gayes of Coastal Carolina University's Center for Marine and Wetland Studies.

In light of the tsunami that impacted Hawaii and the U.S. West Coast following Friday's earthquake in Japan, Dr. Gayes says the Pacific Ocean basin is more known for producing tsunamis than the Atlantic, but there are seismic features in the Atlantic that could produce a tsunami on the East Coast.

"They're generally not as frequent, they're not as massive, but the mechanisms are there."

One of the most massive earthquakes in US history struck Charleston in 1886, destroying dozens of buildings and killing 60 people. But Gayes says, as far generating a tsunami, the Charleston fault line isn't the one South Carolinians should be worried about.

"The condition out in the Canaries (islands) and the trench in the Caribbean and some of slump potentials on the continental slope are the more likely generators in the Atlantic basin," Gayes said.

Low-lying areas have been evacuated and beaches closed in the aftermath of the massive quake that struck Japan Friday morning. Waves as high as 8 feet were reported in some areas along the California coast.

That may not sound dangerous, since waves along the Grand Strand regularly hit 6 to 10 feet on a typical day. But Gayes says those waves will curl and break and dissipate harmlessly after a few seconds. Tsunamic waves are much different.

"These things are rising walls that come up over many minutes and so they will inundate much further and much broader areas, particularly where the coast might funnel that wave in a little bit."

Gayes says a tsunami can cause massive destruction in low-lying areas, similar to the damage caused by a hurricane surge.

Still, he says it's important for people on the South Carolina coast to put the threat of a damaging tsunami in perspective.

"Big, nasty events are relatively infrequent," Gayes said. "Here, our bigger issues really are the tropical storms and things like that and even for that matter, we're not right in a very high hit rate for some of the hurricanes as we've seen in our last 20, 30 years."

Do you feel like a tsunami is something you need prepare for? Or are you more likely to just take your chances and deal with it if and/or when it happens?