
Android early earthquake warnings
How Android Earthquake Alerts System Works
Earthquakes happen daily around the world, with hundreds of millions of
people living in earthquake prone regions. An early warning can help
people prepare for shaking, but the public infrastructure to detect and
alert everyone for an earthquake is costly to build and deploy. We saw
an opportunity to use Android to provide people with timely, helpful
earthquake information when they use Google search, and a few seconds
warning to get themselves and their loved ones to safety if needed.
Android Earthquake Alerts System detects earthquakes around the world
and can alert Android users before shaking starts.
Detecting an Earthquake
In California, Washington, and Oregon, we partner with the
ShakeAlert®
team to distribute alerts provided by their system. ShakeAlert uses a
network of 1675 seismic sensors to detect earthquake shaking, and
analyzes that data to determine the location and size of the earthquake.
The
ShakeAlert®
system then sends a signal to Android Earthquake Alerts System, which
then sends an earthquake alert directly to Android users.
Outside of these U.S. states, we use a crowdsourced approach to detect earthquakes. All smartphones contain tiny accelerometers that can sense vibrations, which indicate that an earthquake may be happening. If the phone detects something that it thinks may be an earthquake, it sends a signal to our earthquake detection server, along with a coarse location of where the shaking occurred. The server then combines information from many phones to figure out if an earthquake is happening. This approach uses the 2+billion Android phones in use around the world as mini-seismometers to create the world’s largest earthquake detection network; the phones detect the vibration and speed of shaking of an earthquake, and alert Android users in affected areas accordingly.
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Earthquake detections can also be viewed on Google Search. Simply search
for “Earthquake near me” - if you’ve felt shaking - to get additional
information about any seismic activity near you.
Alerting Users During an Earthquake
Android has two types of notifications designed to alert users about an
earthquake. Both alert types are only sent for earthquakes of magnitude
4.5 or greater.

Take Action Alert
[Moderate / Extreme Shaking]

Be Aware Alert
[Weak / Light Shaking]
Be Aware Alert
- Designed to give you a heads up for light shaking, and provide more information when you tap on the notification.
- Only sent to users who will experience MMI 3 & 4 shaking during an earthquake of magnitude 4.5 or greater
- Respects the Volume, Do Not Disturb and Notification settings on your device.
Take Action Alert
- Designed to get your attention before you experience moderate to heavy shaking, so that you can take action to protect yourself.
- Only sent to users who will experience MMI 5+ shaking during an earthquake of magnitude 4.5 or greater.
- Will break through Do Not Disturb settings, turn on your screen and play a loud sound.
Earthquake Safety Information
Tapping on either of the alerts will present Earthquake safety
information, which consists of simple steps that you can take to keep
yourself safer after an earthquake. It also provides a detailed map of an
early estimate of the earthquake location and magnitude.
