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How can an earthquake alert arrive before strong shaking?

An earthquake alert can beat the strongest shaking to a distant location even though the earthquake has already started. Detection and communication can travel ahead of the damaging waves, but nearby places may receive little or no warning.

4–5 min

Questions you could explore

  • What has to happen before an alert can be issued?
  • Why is there a region where the warning arrives too late?

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3–5 min

Why is the sky blue, but a sunset often red?

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2–3 min

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How can an earthquake alert arrive before strong shaking? | Speech Topic | speaking.app