If you live in an earthquake-prone area, you’re probably used to hearing the earth shake without warning. But in recent years, technology has allowed governments and private companies to develop earthquake warning systems.
These systems, such as Google’s Android Earthquake Alerts System, cannot detect earthquakes, as such technology does not yet exist. But it can give people a seconds-long warning to take action to prepare.
On October 25, a 5.1-magnitude earthquake struck the San Francisco Bay Area. Twitter users He thanked Google for the warning, and said they found a warning of an upcoming earthquake a few seconds before they felt the earth shake.
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Google earthquake detection is available worldwide but is most advanced in California, Oregon and Washington, where additional seismometer systems can communicate with Google servers.
Google’s earthquake warning uses data from Android phones and the phones’ accelerometers, which are small sensors that, when used together, can detect earthquakes before they strike. Accelerometers in phones are how Android phones can alert people in places that don’t have seismic systems for earthquakes.
Those sensors send signals to Google’s earthquake detection server, along with a rough estimate of the quake’s location, and Android users are notified of earthquake activity.
Technology is constantly changing to help keep us safe, like Google’s earthquake detection system and Apple’s crash detection. iPhone users can also receive earthquake alerts — through iPhone settings elsewhere, or through a third-party app. This week’s shakeup compared Android and iPhone alerts.
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David Kleidermacher, a member of Google’s security team, Plans that Google has registered for “unlocking capabilities,” while other companies have not. He pointed out that Apple did not notify the iPhone user in his office about the earthquake until after.
Google says that seismometer systems are expensive to build and operate, so the solution is to use Android phones as mini seismometers. But as Robert de Groot, a member of the ShakeAlert team, told Wired, for phones to work as earthquake detectors, people have to be close to the earthquake.
As Google refines the technology, they hope to notify people of earthquakes with more seconds between notification and an active earthquake. The technology is still new and underdeveloped, so it may take some time before people have a minute to cover themselves.