A coalition of university partners with the United States Geological Survey (USGS) are developing and testing earthquake early warnings for the west coast of the United States. The work is being funded by the Gordon and Betty Moore Foundation and the USGS.
The project partners:
- United States Geological Survey
- California Institute of Technology
- University of California Berkeley
- University of Washington
- Eidgenossische Technische Hochschule Zurich
- Southern California Earthquake Center
The objective of earthquake early warning is to rapidly detect the initiation of an earthquake, estimate the level of ground shaking to be expected, and issue a warning before significant ground shaking starts. This can be done by detecting the first energy to radiate from an earthquake, the P-wave energy, which rarely causes damage. Using P-wave information, we first estimate the location and the magnitude of the earthquake. Then, the anticipated ground shaking across the region to be affected is estimated and a warning is provided to local populations. The method can provide warning before the S-wave, which brings the strong shaking that usually causes most of the damage, arrives.
Studies of earthquake early warning methods in California have shown that the warning time would range from a few seconds to a few tens of seconds, depending on the distance to the epicenter of the earthquake. This is enough time to slow and stop trains and taxiing planes, to prevent cars from entering bridges and tunnels, to move away from dangerous machines or chemicals in work environments and to take cover under a desk, or to automatically shut down and isolate industrial systems. Taking such actions before shaking starts can reduce damage and casualties during an earthquake. It can also prevent cascading failures in the aftermath of an event. For example, isolating utilities before shaking starts can reduce the number of fire initiations.