When a 6.0-magnitude quake hit Napa County, Calif., on Aug. 24, 2014, as much as 10 seconds advance notice went out to several dozen test volunteers in the San Francisco Bay Area. A 2014 file photo shows a facade in Napa following the earthquake.
John Vidale was sitting in his office at the University of Washington in Seattle when a computerized voice on his Mac warned shaking from a nearby earthquake would hit in exactly two seconds.
Mr. Vidale didn’t feel the earth move because the April 26 temblor was only a 2.5 magnitude quake, too small to be felt. “But if it was a big one,” he would have a crucial few moments to “go to a corner of my office and make sure nothing falls on me,” said Mr. Vidale, director of the Pacific Northwest Seismic Network based at the university.
For years, efforts have been under way to outfit the earthquake-prone West Coast with a system to warn residents before the shaking from a quake strikes—something like the test system that gave Mr. Vidale his alert. Bureaucratic barriers and a lack of funding have slowed its implementation.
Now, scientists are pressing government officials to speed up the process, touting evidence that the decadelong test phase of a U.S. system is ready for wide deployment.
Scientists have said California and Washington state are overdue for a major quake that could cost billions in economic losses and disrupt some of the country’s major transportation and trade routes.
Like many developed places in earthquake zones, California has invested heavily in protecting cities from violent shaking. The work has included reinforcing bridges, overpasses and buildings. But many residents and office workers are still vulnerable because of certain types of construction expected to collapse in heavy shaking.
A warning system could help save lives in the event of a major quake, giving cities, schools and hospitals a chance to prepare and individuals a chance to take cover.
At an April conference of the Seismological Society of America in Reno, Nev., researchers presented data that showed a test system has largely worked.
When a 6.0-magnitude quake hit Napa County, Calif., on Aug. 24, 2014, for example, as much as 10 seconds advance notice went out to several dozen test volunteers in the San Francisco Bay Area—including to San Francisco’s public transit system, known as BART, which in 2012 enabled slowing or stopping trains based on the alerts.
“We’re at the point where the technology is basically there,” saidGraham Kent, director of the Nevada Seismological Laboratory at the University of Nevada, Reno. “But the challenge is to get a coordinated plan” to bring the system to the public.
The U.S. Geological Survey, the federal science agency that studies quakes and other natural hazards, has said the system could be deployed across the West Coast in as little as two years if Congress fully funds its portion of the $38 million needed to complete the $100-million system. But the money has been slow to come.
California Gov. Jerry Brown, in his revised budget plan, is calling on legislators to set aside $10 million to help complete the network in the Golden State.
The network includes seismic sensors to detect the earthquake’s first waves, telecommunications equipment to relay them on, monitoring stations to triangulate a quake’s size and a central operations center to analyze the data and send alerts out. The network will operate only along the West Coast and possibly Hawaii, with the first public alerts likely starting in the Los Angeles and San Francisco areas, said Doug Given, coordinator of the early-warning system for the USGS.
Modeled after an early-warning system in Japan, the U.S. network would provide as much as several minutes advance notice from the time a major earthquake strikes to when its violent shaking hits an urban area. Japan’s system has been credited with potentially saving thousands of lives in past earthquakes.
But such systems are no guarantee. Those directly on top of a fault rupture wouldn’t always receive a warning.
Much as the distance from a lightning strike can be determined by how long it takes for the sound of thunder to arrive, seismic sensors can detect the first weaker-shaking energy waves that ripple out from an earthquake before the slower, vibration waves follow.
Scientists have long known that vibrations from earthquake waves could be detected, but until recently the technology wasn’t advanced enough to do so reliably. Mexico deployed a system after a 1985 earthquake killed more than 10,000 people, while Japan’s system was set up after the 1995 Kobe quake left at least 6,000 people dead.
In 2006, the USGS started work on the West Coast network as a demonstration project, but the work picked up speed after the 9.0 magnitude earthquake that struck Japan’s Tōhoku region in 2011, seismologists say.
“Tōhoku showed the early-warning system worked incredibly well,” said Ronni Grapenthin, assistant professor of geophysics at New Mexico State University and a researcher in the earthquake project.
Soon after that quake, the Gordon and Betty Moore Foundation awarded $6 million to help jump-start an early warning effort that had been getting along on about $1.5 million a year. In February, the foundation added another $3.6 million to the effort.
The money has gone into beefing up the West Coast’s network of earthquake sensors, as well as telecommunications equipment to relay the alerts.
“Any opportunity to have advance notice of an impending event moves you away from the reactive phase to the proactive phase,” said Gary Gordon, business continuity leader at Boeing Co., whose operations in Washington and California are among dozens of public and private facilities which have volunteered to test the technology.
For example, he said forklifts hauling an airplane wing would have time to lower the load to the ground so it won’t fall and potentially cause injuries and damage. Other voluntary testers in the system, which has been in the works for 10 years, include the cities of Seattle and San Francisco, the Bay Area Rapid Transit District, MicrosoftCorp. and Intel Corp.
Among what’s needed is more equipment to detect quakes. While major cities like Los Angeles and San Francisco have fairly extensive coverage, more sensors are needed to build out the network so less-populated areas and threatening faults are covered, Mr. Given said.
Once the system is complete, resident would receive alerts including on mobile phones, such as a faster version of the child-abduction Amber alerts. The real task, Mr. Vidale said, will be in delivering the message many ways and in educating the public what to do when they get a warning—such as whether to evacuate a building.
“If you have five seconds, teacher can get the kids under the desk,” Mr. Vidale said. “But if you have 30 seconds to a minute, it gets a lot more complicated.”
Write to Jim Carlton at jim.carlton@wsj.com
http://www.wsj.com/articles/scientists-renew-push-for-earthquake-warning-system-on-west-coast-1463477410
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