VENEZUELA: Two powerful earthquakes that struck Venezuela on Wednesday caused widespread destruction, with several buildings collapsing and reports of severe damage in various areas.
These earthquakes of magnitude 7.1 and 7.5 are considered the most powerful earthquakes to hit Venezuela in the past century. However, after this disaster, another question also became the center of attention of people: how did Google warn some users before the earthquake was felt?
Several users on the social media platform X shared screenshots in which they claimed to have received an advance warning of the earthquake from Google.
One user said that he received a notification from Google a few moments before the earthquake, which warned of an earthquake of about 6.2 magnitude and was told that the earthquake was recorded about 341 kilometers away.
According to experts, this technology is directly related to smartphones. Every modern smartphone has a special sensor called an accelerometer.
This sensor is usually used to detect the rotation of the phone’s screen or movement, but it can also detect tremors in the ground.
When an Android phone senses a tremor that could be an early sign of an earthquake, the phone sends a signal to Google’s Android Earthquake Alerts system. This signal also includes general location information.
Google’s servers then compare the data received from other phones in the same area. If a large number of phones record the same tremor, the system assumes that an earthquake is coming and immediately issues a warning.
According to Google, more than two billion Android phones around the world are part of this network, making this system the world’s largest distributed earthquake monitoring system.
The question also arises, how does Google warn people in advance if an earthquake is coming? According to experts, an earthquake does not come in the form of a single shock but travels in the form of different types of waves. The initial waves, called P-waves, travel at a speed of about 6 kilometers per second and are relatively weak. The S-waves that come after this are more destructive but have a speed of about 3 to 4 kilometers per second.
Android phones sense these initial P-waves and immediately send a notification to Google’s servers. Since digital signals travel close to the speed of light, Google gets a few precious seconds in which it can assess the situation and warn users in the affected areas.
Google explained this by saying, “We are essentially racing between the speed of light and the speed of earthquakes, and fortunately the speed of light is much faster than earthquake waves.”
For example, if the epicenter of an earthquake is 341 kilometers away from a person, Google’s servers can receive and analyze the initial signals of the earthquake and issue an alert before the main tremors arrive.
There are two different types of alerts for earthquakes in the Android system. “Be Aware Alert” informs about mild tremors, while “Take Action Alert” warns before moderate or severe earthquakes so that people can take protective measures. By clicking on these alerts, more information can be seen, including precautions during and after the earthquake, location and initial estimates of the intensity.
The system has been active in India since 2023 on Android 5 or later versions. However, mobile data or a Wi-Fi connection must be active to receive alerts. If a user does not want to receive such warnings, they can also go to their phone’s settings and turn off earthquake alerts.
Experts say that although this system does not predict earthquakes in advance, detecting initial tremors and warning a few seconds in advance can also play an important role in saving lives.
