The California Governor’s Office of Emergency Services is working diligently with other governmental and nongovernmental organizations to bring earthquake early warning to California. Major milestones in these efforts were the creation of the California Earthquake Early Warning Program (CEEWP) and the California Earthquake Early Warning Advisory Board by Senate Bill 438 (Hill and Hertzberg). These efforts were funded by $10 million dollars allocated in the 2016-17 budget. This funding is being used to install or upgrade over 180 seismic sensors, which will allow them to transmit real-time data. Funding is also going to the research and development of new technologies to receive warnings and provide auditory or automated actions and provide communication, education, training and outreach. The Governor’s Proposed Budget for 2018-19 includes $15.75 million dollars to complete sensor installation or upgrade the 283 remaining sensors and support the Earthquake Early Warning Advisory Board. Cal OES is working diligently with public, private and non-profit partners to develop new pathways to get alerts to people within the next year. One method is to use datacasting, excess transmission with digital television signals to provide information to specialized receivers sparking auditory and automated actions. The distribution technology is being tested in the first part of 2018. Earthquake early warning will be moving from the lab and test cases to ones that can be seen and protect larger groups of people.
Earthquake Early Warning (EEW) systems use science, state-of-the-art monitoring technology, and innovative delivery methods to alert people and devices before the anticipated strongest shaking arrives in affected regions. Seconds to minutes of advance warning can provide opportunity to take life-saving actions like Drop, Cover, and Hold On.
When an earthquake occurs, two main forms of seismic waves are produced. The strongest shaking resulting from the S-wave, that moves more slowly, is preceded by the weaker, less damaging P-wave. Technology now exists that can detect the energy from P-waves to estimate the location and the magnitude of earthquakes and provide warning before the more destructive S-waves arrive. This makes it possible to detect a large earthquake and broadcast a warning to projected areas of impact before the strong shaking that radiates from the epicenter, or earthquake source.