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What are tides?

A tide is the periodic rise and fall of the water of oceans, seas, bays and so on caused by the gravitational interactions between the earth, moon and sun (Australian Hydrographic Service glossary).

Find out about water levels, tides and currents, including:

  • What makes the tides.
  • History of tidal analysis and prediction.
  • Tide predicting machines.
  • How do you measure water levels.
  • Why do you measure water levels.
  • The challenge of measuring water currents.

The tidal glossary – Manly Hydraulics Laboratory explains tidal terminology. The Australian Hydrographic Office also have a tidal glossary.

Get information about tidal research and predictions from the National Tidal Unit – Bureau of Meteorology.

Last updated
24 August 2017