What would you do with 10 seconds of warning time before a major quake on the San Andreas Fault started shaking at full strength? Seismologists visited Capitol Hill to talk about an early warning system for the West Coast.
UC Berkeley seismologist Richard Allen was working his way through a flood of emails when a loud, annoying voice began counting down the seconds until shaking would begin from a not-too-distant earthquake. If the voice didn't get his attention, the blasts of an electronic horn did.
Luckily, said Allen, the quake was moderate, not "the big one." But eventually, he says, all California could become familiar with the warning.
Allen belongs to a team of scientists creating an earthquake early warning system. Sensors up and down the West Coast would detect the first seismic waves of a quake, and within seconds, would feed the information to utility companies, transit systems, hospitals and schools – and citizens.
Allen said this means that you can "actually get information out before you start to potentially lose your communications infrastructure." He said an earthquake early warning system could have provided as much as a 20-second warning when the 1989 Loma Prieta quake struck the San Francisco Bay Area.
Bill Leith, a seismologist for the US Geological Survey, said even a 10-second warning about severe shaking to come is enough time to trigger automated controls. Those few seconds could be enough time to stop a train, halt laser eye surgery, or duck under a sturdy table.
"For example," he says, "the slowing and stopping of trains." Or delaying airplane landings. "You don’t want to be landing a big 747 on the runway while it’s shaking." Highrise building managers could also freeze elevators at floors to let people out.
Early warning messages would spread via cellphone, computer, and radio and television.
Japan has used a similar early warning system for three years. Nearly half the population got a warning about the shaking to come from last year's magnitude-9 quake in northern Japan. An automatic system halted two dozen bullet trains across Japan; not one of them derailed.
It will take another three years before the warning system is fully up and running in California - but first, the US Geological Survey needs $150 million to finish the project.
That’s why USGS personnel spent the day briefing Congressional staffers. Much of the sensor system is already in place, federal stimulus money is picking up some of the cost.
Southern California Edison, the Metrolink commuter rail system and emergency officials throughout the state have begun testing a warning system. The Bay Area Rapid Transit system has already put an automatic braking system in place.