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How Pacific navigators learned to read ocean waves

Marshallese navigators learned relationships among islands and waves, supported by stick charts such as the mattang, a teaching model. These objects were not ordinary scale maps to unfold at sea. Explore what a chart can teach and what still depends on experience in the water.

8–10 min

Questions you could explore

  • What can a diagram teach that still requires experience on the water?
  • How does a mattang represent wave relationships rather than distances on a conventional map?

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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
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 Pacific navigators learned to read ocean waves | Speech Topic | speaking.app