WAIKOLOA, Hawai'i — A group of University of California scientists is developing a system that could send out warnings 20 seconds before an earthquake strikes.

The Earthquake Alarm Systems, or ElarmS, and a plea for better collaboration were among the highlights at last week's annual meeting of the Seismological Society of America, where nearly 500 seismologists gathered at the Hilton Waikoloa Village.

The annual meeting coincided with the six-month anniversary of Hawai'i's Oct. 15 quakes, which shook much of the state out of bed, caused numerous injuries and left homes, businesses, roads, walls and water systems with up to $200 million in damages.

The 6.7-magnitude temblor under Kiholo Bay on the Big Island was the strongest quake in the nation in 2006. It was centered at a depth of 24 miles, deep enough not to trigger a tsunami.

An ElarmS might have alerted residents that the shaking was coming.

The ElarmS has its roots in Japan in the 1960s, when authorities sought to limit damage to high-speed trains during earthquakes. Japan, Taiwan and Mexico now have similar early-warning systems in place.

The magnitude of an earthquake can be estimated within one second of the first seismic reading, said University of California, Berkeley assistant professor Richard Allen. At 6 seconds, computers can predict the reach of the quake and send out warnings.

Since last year, the team has mapped 160 seismic events of between magnitude 3.0 and 5.0 in northern California. Most were detected within 10 seconds of origin.

The amount of warning time people would receive depends on their proximity to the epicenter. The farther from the event's origin, the more warning time would be available, perhaps as much as 50 seconds.

"An early-warning system will help many people in many earthquakes," Allen said. "We're looking at a 10- to 20-second window."

That may be long enough for people to seek cover or get out of potentially dangerous situations, he said.

In addition, the system eventually could be fully automated. Drivers could be warned not to pull over, planes not to land, trains halted on the tracks, gas lines and power plants shut down, machinery shut off.

"It's more of a way to reduce hazards," Allen said. "That's really our expectation. Unfortunately, I do not believe we will be predicting earthquakes in the foreseeable future."

Still, the critical component of the system will be getting the message out, he said.

"We have the information before most people even feel the first vibrations," he said. "What we need is a robust communication system."

For example, cell towers could alert every cell phone within range and every computer screen could issue a warning, Allen said.

Barry Hirshorn, geophysicist at the Pacific Tsunami Warning Center, said an ElarmS likely would work in Hawai'i if the number of seismic monitors was increased substantially from the current 70 across the state.

"The technology exists, but we need the infrastructure, especially on the Big Island and south Maui," he said. "Then we need the capability to take the technique and put it in at Hawaiian Volcano Observatory and PTWC. We've got plenty of earthquakes to test. I'd love to play with it for a little while."

Big Island Mayor Harry Kim, a former Civil Defense administrator, asked that scientists don't simply do the research, but help find ways to share it.

"All systems of technology are useless," Kim said, "unless they are closely integrated or in harmony with those responsible in the mitigation sector."