for National Geographic News
After late or missed warnings, operators are struggling to figure out why a recently launched earthquake early-alert system in Japan isn't working as planned.
The system, run by the Japan Meteorological Agency (JMA), is designed to give people in the quake-prone country up to two minutes' warning of approaching shock waves.
"If the system works properly, then it will contribute significantly to reducing the impact of disasters," said Masahiko Murata, deputy director of the projects department at the Disaster Reduction and Human Renovation Institution in Kobe.
"Even a few seconds' warning will enable construction sites to stop heavy machinery, let people get out of elevators in tall buildings, or give time for trains to come to a stop."
But an earthquake in January failed to trigger an alert, and another in April saw the warning arrive too late.
Critics are now concerned that further failures may cause the public to distrust the system and ultimately ignore warnings.
"The alert is issued after a seismic wave is observed from an earthquake, but there is very little time for us to analyze the data and estimate the scale of the event," said Keiji Doi, JMA's senior coordinator for seismic information.
"There may be errors in determining the exact location of the quake, its magnitude, the energy that has been released, and the intensity," he added.
"We are constantly working on the system and making improvements that we hope will make it more accurate in the future."
The Real-Time Earthquake Information Consortium, a Tokyo-based nonprofit organization, has estimated that the death toll from a major tremor can be reduced by 25 percent if an area receives just a two-second warning.
That figure jumps to 80 percent if a five-second warning is given, enabling people to take cover under tables, stand in doorways, or cover their heads with cushions or bedding.
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