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Comment: 23:18 - 24:36 (01:18)
Source: Annenberg/CPB Resources - Earth Revealed - 25. Living With Earth, Part I
Keywords: "William Bakun", earthquake, "earthquake prediction", "Loma Prieta Earthquake", "seismic wave"
Our transcription: There is yet another strategy for minimizing the impact of earthquakes, a seismic early warning system still in the experimental stage that was installed following the Loma Prieta earthquake.
With this system, the instant a large earthquake is recorded sensors in the ground transmit a signal to receiving stations throughout the area.
You're taking advantage of the idea that once an earthquake occurs and it's detected, you can essentially out-race the seismic waves that are propagating through the ground by sending a radio signal ahead, and so the farther away you are, the more time of warning that you have.
The actual time saved by such a system might only amount to 10 or 20 seconds, but this could be long enough to divert or temporarily immobilize public transportation systems or to simply warn people to take cover and possibly save their lives.
So I think it has some possibilities, and the state and local officials are evaluating how such a system might best be used in future earthquakes.
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