If you live in an area prone to earthquakes, you’re probably used to feeling the ground shake without warning. But in recent years, technology has allowed governments and independent companies to create earthquake warning systems.
These systems, such as Google’s Android Earthquake Alerts System, cannot predict an earthquake because that technology does not yet exist. But it can give people seconds long warning to take action to prepare.
On October 25, a 5.1 magnitude earthquake occurred in the San Francisco Bay Area. Twitter users thanked Google for the warning, saying they received a notification of the next earthquake only a few seconds before they could feel the ground shaking.
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Google’s earthquake detection is available worldwide but is more advanced in California, Oregon and Washington, where more seismometer systems can communicate with Google’s servers.
Google’s earthquake alert uses data from Android phones and the phones’ accelerometers, which are small sensors that, when used together, can detect an earthquake happening right before it hits. The accelerometers in phones are how Android phones can notify people in areas without seismometer systems about an earthquake.
Those sensors send signals to Google’s earthquake detection server, along with a rough estimate of the earthquake’s location, and Android users are then notified of earthquake activity.
Technology is constantly evolving 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 in some locations, or from a third-party app. This week’s earthquake drew comparisons between Android and iPhone alerts.
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David Kleidermacher, a member of Google’s security team, suggestions that Google subscribes to the “power of open”, and other companies do not. He mentioned that Apple didn’t inform an iPhone user in their office about an earthquake until after it happened.
Google says that seismometer systems are expensive to build and use, so the solution is to use Android phones as mini-seismometers. But as Robert de Groot, a member of the ShakeAlert operations team, told Wired, for phones to work as earthquake detectors, people need to be close to the earthquake.
As Google refines the technology, they hope to notify people of an earthquake with more seconds between the notification and an active earthquake. The technology is still new and underdeveloped, so it could be a while before people have even a minute to cover.