Early warning system for earthquakes

Published 13 December 2007

Shake, rattle, and respond: By analyzing earthquakes when and where they strike, a computerized system could save lives

When an earthquake strikes, seismic waves spread from the epicenter, following the patchwork quilt of faults and geology. The violent shaking these waves may trigger can topple buildings, rupture water mains, and wreak havoc on industrial infrastructure. By making quick computer analyses in seismographic stations near the epicenter, however, warnings can be relayed in seconds, allowing people to take safety precautions and critical infrastructure to be shut down, scientists reported this week at the fall conference of the American Geophysical Union in San Francisco. Scientific American’s David Biello quotes seismologist Richard Allen of the University of California, Berkeley to say that “What we’re doing with early warning is predicting the ground motion after we know the earthquake is underway. Any computerized system can start to do things very rapidly, rapidly enough so we can implement our response before the ground stops shaking.” Such a system, developed by Allen and his colleagues, is currently being tested in California’s roughly 300 seismometer stations and provided 10 seconds of warning for the San Jose temblor that measured 5.4 on the Richter scale on October 30.

Japan and Europe already have such warning systems, which have proved useful in preventing fires, one of the major secondary impacts of powerful earthquakes. “Actions that can be made to prevent fires is just to have [an] automatic system to switch off gas supply, also electricity,” says geophysicist Paolo Gasparini of the University of Naples