9 Year Cycle

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Whether large bores occur after new moons or full moons varies due to the fact that there is a nine-year cycle. The cycle runs as follows:


    - highest tides occur following a new moon

    - the highest tides at new and full moons are approximately equal

    - highest tides occur following a full moon

    - the highest tides at new and full moons are approximately equal


The cycle then starts again. The cycle is shown in the following diagram:

9 Year Cycle