Google Has Quietly Been Detecting Earthquakes by Sensing Rumbling in Android Phones For Years

Google has for years been harnessing the power of its Android smartphones to detect and measure tens of thousands of earthquakes.

In a new paper published in the journal Science, researchers from the search giant described how they used motion sensors from its two billion-strong network of phones running Android between the years 2021 and 2024 to detect and alert quakes to users in almost 100 countries around the world.

Known as "Android Earthquake Alerts" (AEA), this early warning system has uses the smartphones' accelerometers to detect telltale vibrations as they happen and inform residents of quakes in their areas. With its two-tiered severity levels — the weaker "be aware alert" for lower-magnitude quakes that sends typical push notifications, and the more pressing "take action alert" for moderate or extreme shakes that issues a loud beeping alarm that overrides "Do Not Disturb" settings — Google boasts that it has warned of more than 11,000 quakes.

While such a system has invariably saved lives, however, AEA is far from flawless.

In the case of Turkey's deadly quakes in 2023 that claimed more than 55,000 lives and injured over 100,000 people, the company now admits that it erroneously sent its lower-level notifications to hundreds of thousands of people — a massive failure during one of the deadliest natural disasters in recent history.

Both in the Science paper and in a statement to BBC, Google admitted that it only sent 469 "Take Action" alerts during the first of the two earthquakes that struck Turkey and Syria in February 2023, and instead mass-notified half a million people with the "Be Aware" version, the less severe of the two warnings. Because the first earthquake occurred at around 4:15 in the morning, that quieter warning likely went unseen by people who were asleep and had their phones silenced.

That discrepancy appears to be the result of bad seismic readings from the phones' sensors. Initially, the system's algorithms estimated that the first quake was between a 4.5 and 4.9 on the moment magnitude scale (MMS), but it was actually a far more serious 7.8. During the second quake, the AEA also underestimated the magnitude, sending only 8,158 "Take Action" alarms and almost four million "Be Aware" alerts. (That shoddy algorithm, the company says, has since been updated.)

Until now, Google deflected blame for the system's failure, even after the BBC investigated the AEA in the aftermath of the quakes and found it to be severely lacking.

Though this sort of admission is better late than never, it's still concerning that Google took more than two years to admit the system's failures during the Turkey earthquakes. With so many people relying on the tech monolith for life-saving alerts, taking accountability for the AEA's failures is paramount — and that accountability should have been much swifter.

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