Mexico's life-saving warning system

In 1991, Mexico launched the world’s first public earthquake early warning system, giving people precious seconds to get to safety before strong shaking begins.

The system was developed in the aftermath of the devastating 1985 Mexico City earthquake, which killed thousands and highlighted the need for advance warning.

Director of the Seismic Instrumentation and Record Centre (CIRES) in Mexico, Juan Manuel Espinosa Aranda, helped pioneer the system.

Today, the network uses nearly 100 sensors and warns millions of people through mobile phones, radio, television and public loudspeakers.

Juan Manuel tells Gill Kearsley how the groundbreaking system was created.

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(Photo: The alarm system in 2015. Credit: Alfredo Estrella/AFP via Getty Images)