Public understanding of the state's tsunami siren warning system is so poor that University of Hawai'i scientists will launch a $500,000 study on how to re-train residents and the authorities who manage emergency response.

The hope is to identify the most effective way to educate residents about official warnings and the natural signs that a tsunami may be coming, such as earthquakes and extreme tidal changes.

Bruce Houghton, a volcanologist with the UH School of Ocean and Earth Science and Technology, said those responsible for emergency management have "overrated" the public's preparedness and understanding of tsunamis.

"For example, during the tsunami that hit Hawai'i in 1960, researchers showed that only about 5 percent of those affected by the disaster in Hilo reacted appropriately to the official sirens used to alert the people although most connected the sirens to the idea that a tsunami was expected," Houghton said in a news release.

Public information about warnings has focused on supplying accurate information without considering how people interpret or use it, he said.

"It's scary, really, because there is a lot of assumption that we have the most successful system around," Houghton said. "But it has been so long since it has been really tested that we don't know what the public is going to do."

The state has been hit twice in the past 100 years by devastating tsunamis, including one in 1946 that prompted the siren warning system, which is tested on the first state workday of each month.

The new study, which is funded by the National Science Foundation, will include physical scientists, psychologists and social scientists from the United States, Thailand, Australia and New Zealand.

The team of researchers will study "psychological variables" that influence preparedness in tsunami-prone areas.

"What we are hoping for is a much more intelligent impression of what makes people formulate a plan and act on their plan," Houghton said.

SIREN DEPENDENT

A recent survey of nearly 1,000 people in five communities across the state showed only 12 percent had an accurate understanding of the siren warning system, said Chris Gregg, an associate professor of geology at East Tennessee State University. Gregg earned his Ph.D. at the University of Hawai'i earlier this year by studying the public's understanding of the state's tsunami warning system.

The survey found that people depended on the sirens rather than the changes that occur in the ocean as a killer wave approaches, he said in a news release.

"This is problematic because the understanding of the official system is so low," he said.

STUDY WELCOMED

Maj. Chuck Anthony, spokesman for the Hawai'i Department of Defense, which oversees civil defense for the state, said emergency planners feel the public is adequately prepared for a tsunami generated far from Hawai'i. The lead time from such a tsunami gives authorities enough time to warn the public.

"The one thing we would like to be able to do is have a virtually instantaneous response for an earthquake off somewhere like the Big Island," he said.

An earthquake that close could send a tsunami to a local shoreline within minutes.

But any study that increases public awareness is a good thing, he said.

"It is a continuous public education campaign," he said. "Even though longtime Hawai'i residents may be aware, you have new people coming in so you have to do constant reminders to be sure that everyone is getting the word in case of a tsunami."

HIGH-RISK AREAS

The study will look at preparedness plans of seven communities in the United States: Kodiak, Alaska; Ocean Shores, Wash.; Seaside, Ore.; San Diego; the Florida Keys; Aguadilla, Puerto Rico; and Kaua'i.

The areas were picked because they are at risk for locally generated and distant tsunamis, among other factors.

Without an effective warning system, Hawai'i could experience the kind of high death toll along coastal communities that southeast Asia experienced last December, Houghton said.

Reach Mike Gordon at mgordon@honoluluadvertiser.com.