Yesterday, a 5.1 magnitude earthquake hit the San Francisco Bay Area, the strongest in the region in nearly a decade. However, an early warning system alerted those who carry an Android phone to the quake before the shaking began. The Governor’s Office of Emergency Services reported that around 90,000 people in the San Francisco area received an alert on their phones seconds before they felt the earthquake.
Crowdsourced Data from Android Smartphones
In 2020, Google introduced the “Android Earthquake Alerts System,” which uses crowdsourced data from Android smartphones to provide an early warning when an earthquake is about to strike your location. This system has been integrated with “ShakeAlert,” a service developed by Berkeley researchers in California.
The system uses sensors on your phone to detect an earthquake’s “P-wave,” a smaller initial wave that arrives before the more destructive “S-wave.” The system can detect an earthquake by using phones in the surrounding area and offer a few seconds of early warning.
My Android phone alerted me to today's earthquake several seconds before it struck. Office visitor with an iPhone received the alert several seconds after. We were very close to the epicenter. #powerofopen
— David Kleidermacher (@DaveKSecure) October 26, 2022
Brian Ferguson, Deputy Director of Crisis Communication and Public Affairs at the Governor’s Office of Emergency Services, commented, “We have the most advanced technology in the country in terms of helping people get notifications even before shaking starts. And this is one of the biggest events since the system launched.”
Examples of the System in Action
Earthquake in SF Bay Area today. Yellow/red represents shaking Android phones acting as seismometers. Circles are our inferred estimate of P & S waves. Earthquake alerts sent instantaneously to surrounding phones before the waves hit pic.twitter.com/8pumt19ReI
— Dave Burke (@davey_burke) October 26, 2022
Since its implementation, Google has shared examples of when the system has successfully warned users. For example, during a 4.5 earthquake in Los Angeles and a 6.7 quake in the Philippines in 2021, many reported that the system provided them several seconds of warning before they felt the quake.
Google’s VP of Engineering for Android, Dave Burke, posted a tweet hours after the San Francisco earthquake that showed what the system detected. He shared the system’s estimate of the P and S waves.
Power of Open
The early warning notifications on Android phones were almost instantaneous, with many reporting the seconds of warning on Twitter. This has led to some iPhone users wondering why Apple’s iPhones don’t provide the same functionality. A member of Google’s security team for Android expressed that this comes from the “power of open,” describing his experience of seeing his Android phone alert him to the quake seconds before it hit.
At the same time, an official visitor’s iPhone received an alert after the quake had struck. For iPhone users, downloading the MyShake app and setting their location is necessary to receive the alerts.
The “Android Earthquake Alerts System” has shown that it can provide critical seconds of warning before an earthquake strikes. With earthquakes becoming more common in various parts of the world, this technology could be essential in providing vital information to those in harm’s way.