An early warning system designed to give people crucial seconds of warning before earthquakes delivered on its promise Monday. It buzzed through half a million phones before a 6.2 magnitude earthquake that struck northwestern California, the largest earthquake since the system, called ShakeAlert, swept across the state. The Guardian reported.
ShakeAlert pulls information from the United States Geological Survey (USGS) sensor network. If data from those sensors indicates that there will be a major shaking in an area, the people who live there receive alerts through the MyShake app (if they have downloaded it) or through the wireless emergency alert system on their phones. Alerts are also sent to Android users through a partnership between Google, USGS, and the California Office of Emergency Services.
The epicenter of Monday’s earthquake was off the coast of a small town called Petrolia, and about 45 miles from the nearest population center, Eureka. People reported receiving alerts about 10 seconds before the tremors started, Robert de Groot, USGS ShakeAlert coordinator, He said The Guardian, making it a successful proof of concept for the first substantial earthquake handled by the system. The earthquake did not cause great damage in the area and there were no fatalities.
The ShakeAlert system was first introduced in Los Angeles in 2018, before expanding to all of California in 2019.The system was operational in Los Angeles when a 6.4 magnitude earthquake struck about 150 miles outside of the city, but did not trigger an alert. because the expected tremor in the city was not strong enough to cross the threshold of the application. Users complained that they did not receive an alert despite feeling tremors, so the app developers lowered the threshold before launch statewide.
Now, the scientists behind ShakeAlert can use the information from this most recent earthquake to improve the system again for the next time. “We are really going to learn more from real earthquakes” by Groot. He said The Guardian. “It gives us the opportunity to use the system and learn how to do a better job of alerting people.”