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Why can two “100-year floods” happen close together?

The name sounds like a timetable: one enormous flood, then a century to wait. A “100-year flood” actually describes a flood threshold with an estimated 1% chance of being equaled or exceeded in a given year. It does not promise a flood-free interval, and the estimate can change as evidence and conditions change.

12–15 min

Questions you could explore

  • What does a recurrence interval tell us that a calendar cannot?
  • How does the chance over several years differ from the chance in one year?

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Why can two “100-year floods” happen close together? | Speech Topic | speaking.app