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The changing gap between high and low tide

The changing positions of the Sun, Moon, and Earth contribute to spring and neap tides. Local coastlines and basins add complexity, so the basic astronomical pattern does not by itself predict a tide at a particular beach.

5–7 min

Questions you could explore

  • What does “spring” mean in a spring tide?
  • How is tidal range different from the time of high tide?

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A flat map can warn you that a route climbs sharply before you ever see the hill. Contour lines join places of equal height, and their spacing adds information about how quickly the ground rises.

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How can lines on a map show a steep hill?

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How can an earthquake alert arrive before strong shaking?

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4–5 min

How can an earthquake alert arrive before strong shaking?

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The changing gap between high and low tide | Speech Topic | speaking.app