If you live in an earthquake-prone area, you’re probably used to feeling the earth shake without warning. But in recent years, technology has enabled governments and independent companies to create earthquake warning systems.
These systems, like Google’s Android Earthquake Alerts system, cannot predict an earthquake because this technology does not yet exist. But it can give people a few seconds warning to take steps to prepare.
On October 25, a magnitude 5.1 earthquake occurred in the San Francisco Bay Area. Twitter users thanked Google for the warning, saying they had received a notification of impending earthquake seconds before feeling the ground shake.
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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 just before it hits. Phone accelerometers are how Android phones can notify people in areas without seismometer systems of an earthquake.
These sensors send signals to Google’s earthquake detection server, along with an approximate calculation of the location of the earthquake, and then Android users are notified of earthquake activity.
Technology is constantly evolving to keep us safe, such as Google’s earthquake detection system and Apple’s collision 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, member of Google’s security team, tricks that Google embraces the “power of openness” and other companies do not. He mentioned that Apple didn’t tell an iPhone user in their office about an earthquake until after it happened.
Google says 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 ShakeAlert’s 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 notification and an active earthquake. The technology is still new and underdeveloped, so it may be a while before people have even a minute to seek shelter.