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Water and oceans · Discover & try

Why does the sea rise and fall?

Reading level 4 of 5 · FluentChange
1 · Shorter sentences5 · More detail

Around the Moon's quarter phases, the Sun and Moon lie in different directions at roughly a right angle from Earth. Their tidal effects partly oppose one another, producing a smaller range called a neap tide. Compare the gap between high and low water, rather than treating neap tide as no tide.

Word help
tidal range

The height difference between high tide and low tide.

spring tide

A larger tidal range around new and full Moon.

neap tide

A smaller tidal range around the quarter Moon phases.

Watch · Try · Explain

See how it works

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Idealised spring-neap comparison; sizes and bulges are exaggerated, with no local tide predictions.

What to look for
  • The alignment of the three bodies
  • The gap between high and low water
  • A smaller range that still includes tides
Explain what you noticed

When does the spring-tide pattern occur?

Keep this idea: Alignment affects tidal range; coastal conditions shape local water levels.

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Source material checked 2026-10-28. Explanations and activities by Nepedia. Agency source links do not imply endorsement.

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