U.S. on Guard for Tsunami Risks

ByABC News
December 28, 2004, 7:01 PM

Dec. 28, 2004 — -- Cannon Beach, Ore., is right on the Pacific coast -- and right in harm's way if ever a tsunami comes.

The town is one of 11 communities, stretching from California to Alaska, that have now been certified by the federal government as "tsunami-ready."

Evacuation routes have been established. Residents have signed up to call each other in emergencies. Loudspeakers have been put up around town -- and are tested, twice a month, with a recording of a cow's mooing. A siren sound would send people running.

"It tells them that high-speed waves are expected and that they should head to high ground," said Alfred Aya, the emergency management chief for Cannon Beach. "Tsunamis are very rare, but you never know when they're going to hit, so we can't afford to take chances."

The disaster in Asia has a lot of Americans asking if such a thing could happen here, and the answer is a sobering yes, but, planners hope, with much lesser consequences.

Two major cases of the last century have made the difference:

April 1, 1946. A tsunami, triggered by an earthquake thousands of miles away near the Aleutian Islands of Alaska, stuck Hawaii without warning. At least 159 people were killed. The city of Hilo suffered the worst damage; most of its waterfront was destroyed.

March 27, 1964: An earthquake struck Prince William Sound, Alaska, and the resulting tsunami destroyed the nearby town of Valdez, now the southern terminus of the Alaska pipeline. The quake registered 9.2 on the Richter scale -- stronger than Sunday's quake off Indonesia. But of the 133 people reported killed, 122 died because of the water, not the shaking earth.

Those two disasters prompted the U.S. government to start tsunami warning systems, first for Hawaii, then for Alaska and the coasts of California, Oregon and Washington State.

The programs, since combined, are relatively small, with a budget of $4.5 million for fiscal 2005. But if they work properly, people will have enough warning to run to safety. In most places, moving inland just a few hundred yards can be the difference between life and death.

"I think the tsunami program in the United States is a model for the rest of the world," said Eddie N. Bernard, director of the Pacific Marine Environmental Laboratory in Seattle. The lab is part of the National Oceanic and Atmospheric Administration.

Over the last decade, under Bernard's guidance, NOAA has deployed six automated buoys off the Pacific Northwest coast, southern Alaska and near the Equator.

Sensing devices on the ocean floor can detect even a small wave passing them, and send a signal to the buoy above. That message, in turn, is relayed by satellite to monitoring stations, where it is matched to earthquake data coming from a network of seismometers.

If a tsunami is confirmed, warnings can go out within seconds. They would be spread by radio, news media and the Internet, and would include those sirens in Cannon Beach.

"When we do sound the alarms, the people responding to them will realize that this is not an everyday occurrence," says NOAA's Dr. Bernard.

But in light of Sunday's disaster, will other countries start their own warning systems? American scientists have been shaken. Some of them urge that the U.S. double the size of its Pacific warning program.

They debate the need for a system in the Atlantic as well, especially because of a distant volcano called Cumbre Vieja volcano, on an island near the African coast. In 2001, researchers Steven Ward and Simon Day, writing in the journal Geophysical Research Letters, predicted that if the volcano erupts and its western flank collapses, a tsunami could reach Florida nine hours later.

There is no consensus about such a risk. But scientists agree in calling for more and better monitoring of the world's oceans.

"I think it's not an expensive undertaking," says Bernard. "I think it's more a matter of an attitude and an effort."