Billions of phones can detect and warn about nearby earthquakes

Your smartphone might be part of the global earthquake early-warning network, with billions of Android devices now capable of providing alerts and contributing to earthquake detection efforts.

Google’s Android Earthquake Alerts system, launched in 2020, has expanded to reach 2.3 billion Android phone and smartwatch users, significantly increasing the number of people who can receive alerts about seismic activity. These devices not only deliver warnings but also utilize their sensors to detect earthquakes.

Professor Richard Allen from the University of California, Berkeley, and his team have developed a system that analyzes vibrations captured by accelerometers in Android devices to determine the magnitude of an earthquake and identify users who are in proximity to the event and need to be alerted.

The system is triggered for earthquakes with a magnitude of 4.5 or higher, utilizing the collective data from the network of Android devices. However, it may not detect all earthquakes, especially those originating from mid-ocean ridges.

Improving the accuracy of earthquake detection has been a key focus for researchers, with advancements made in developing regional models and accounting for sensor variations among different Android devices. The global system’s accuracy now rivals established earthquake early-warning systems like ShakeAlert and the Japan Meteorological Society’s program.

Google’s initiative aims to complement existing seismometer-based systems and provide a valuable source of information for regions without dedicated early-warning solutions. It currently operates in 98 countries and territories, prioritizing areas with high seismic risk and lacking adequate warning systems.

Recent analysis of the system’s performance revealed that it issued alerts for 1279 seismic events with only three false alerts, which were promptly addressed through algorithm updates. Most participants found the alerts to be helpful, with over a third receiving warnings before feeling any shaking.

Android users can receive two types of alerts – Take Action alerts for immediate protective actions and Be Aware alerts for general information ahead of an earthquake. The system continues to explore ways to enhance warning times for stronger shaking events in the future.