Earthquake early warning system for California?

Right now, in the U.S., there’s no public earthquake early warning system. EarthSky spoke with seismologist Richard Allen of University of California, Berkeley. Dr. Allen is working with other scientists to develop an early warning system for California earthquakes.

Richard Allen: The idea is to use relatively new science and modern technology to very rapidly detect the beginnings of an earthquake, assess the hazard that that earthquake poses, and then provide a warning to people if they are in harm’s way.

Dr. Allen said that a 2009 study demonstrated that an earthquake early warning system could work for California.

Richard Allen: We had several moderately-sized earthquakes, magnitude 5.5 earthquakes, during that test, which were detected, correctly assessed as being potentially hazardous earthquakes, with accurate estimates of the ground-shaking that ensued.

He said a few seconds of warning can make a difference when an earthquake strikes.

Richard Allen: If you are an individual at home or at work, you want to just get into a safe zone. That probably means under a sturdy table. Trains can be decelerated and brought to a halt before the shaking occurs. Hazardous machinery and chemical factories with hazardous chemicals can isolate the machinery and isolate the chemical systems, move workers away from the hazardous zones.

Allen said a prototype of an early warning system for California earthquakes should be completed in about three years. He spoke to EarthSky about the January 2010 earthquake in Haiti

Richard Allen: We know how to build buildings that don’t collapse in earthquakes – these were not implemented in Haiti, and we’ve seen the result of that.

EarthSky asked Dr. Allen where the U.S. Is today on a scale of 1 to 10 in terms of being ready for an earthquake in California.

Richard Allen: I would give us a 7 out of 10. And I’m giving it a 7 in the context of the Haiti earthquake that we’ve just seen devastate Port-au-Prince and the surrounding regions. The devastation there was largely due to the fact that the buildings were not built up to very high standards at all. So a very large fraction of the buildings collapsed. And that’s what led to almost the half-million people being killed in that earthquake. In California, we do have much better buildings. In particular, the more recent, the more modern buildings are at much higher standard and are not expected to collapse in an earthquake. However, the reason I don’t give us anywhere near a ten is because of the older buildings, there’s still a danger of collapse.

Dr. Allen spoke of a lack of coverage for earthquake detection in California.

Richard Allen: Right now there are about 400 seismic stations across California that could be used for earthquake early warning. The catch is that they are not evenly distributed in the earthquake, the hazardous earthquake regions. They are concentrated in the Los Angeles region and the San Francisco bay area region. But then there are fairly long sections of the major faults that have very few instruments along them in between the metropolitan areas. To build a really effective warning system, we need to instrument those regions all along the faults.

Our thanks to the US Geological Survey, celebrating the International Year of Planet Earth.