Detailed text transcripts for TV channel - CNN - 20110313:22:47:00
The "p" waves come first. they come much, much faster. when the sensors start detecting this, they know the "s" waves are going to follow. they do the wavy thing and that does all of the damage. thats how they know. theyve got sensors all over the place, like seismographs, similar to what we have in the u.s. and they have dart system on the ocean floor so you can start to detect some of that as well. as soon as a warning is issued theyre alerted by television, radio, smartphone, if they have an ...
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