How Phones Alerted Millions Before Earthquakes Shook Venezuela

Key Points:

• Google’s Earthquake Alerts system, using data from Android phones’ built-in accelerometers, provided early warnings seconds before two powerful earthquakes struck Caracas, Venezuela, despite the country lacking a national early warning system.
• The system detected primary seismic waves (P-waves) and sent alerts to 11.4 million people across nearly 100 countries, including 1.4 million “Take Action” alerts for the strongest shaking areas in Venezuela.
• Unlike government-operated systems relying on underground sensors, Google’s system aggregates data from stationary Android phones to estimate earthquake location and magnitude in real-time, continuously updating alerts as the event unfolds.
• Early warnings give people farther from the epicenter more time to prepare, potentially saving lives by encouraging protective actions such as “drop, cover and hold on” before shaking starts.
• The recent Venezuela earthquakes, magnitudes 7.2 and 7.5, were the strongest since 1900, and firsthand reports indicate the alerts helped raise awareness and readiness among recipients experiencing the quakes.