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A watershed's boundary follows the drainage

A watershed groups the land that drains to a chosen outlet, so a small catchment can also sit inside a larger river basin. The boundary depends on which outlet you are asking about.

5–7 min

Questions you could explore

  • How could the same place belong to both a small and a large watershed?
  • How could a road or artificial drain alter the route water takes across a landscape?

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The same Sun can light a blue afternoon and a red evening

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Earth and weather

How can lines on a map show a steep hill?

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.

2–3 min

How can lines on a map show a steep hill?

Earth and weather2–3 minA 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.

Earth and weather

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

How can an earthquake alert arrive before strong shaking?

Earth and weather4–5 minAn 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.

A watershed's boundary follows the drainage | Speech Topic | speaking.app