Reading the tides: a beginner's guide
Why the sea rises and falls twice a day, and how to read a tide table before you head out.
2 min read
Tides are driven mainly by the Moon's gravity, with help from the Sun. As the Earth turns, most coasts pass through two high tides and two low tides each day.
When the Sun and Moon line up, around new and full moon, the range between high and low is largest: these are spring tides. Halfway between, the range is smaller: neap tides.
A tide table lists the times and heights of high and low water for a place. For walking reef flats or launching a boat, the time of low water is usually the number that matters.
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