Tides

What is Tides?

Within Geography, which covers maps, landforms, weather, climate, population and settlements: understand how our planet and people connect, this topic explains Tides. Geography explains how places, people and natural processes connect, so each topic here combines a clear definition with a visual model.

Check that you can explain Tides in your own words and give one example from everyday life. If you can do that, you have understood the core idea.

Understanding Tides helps you explain patterns on maps and in the news, and make reasoned decisions about places and environments.

Tides in detail

Tides are the regular rise and fall of sea level, caused mainly by the gravitational pull of the Moon, and also the Sun, on the Earth's oceans. Most coasts have two high tides and two low tides each day, about every 12 hours and 25 minutes.

Spring tides, with the highest high and lowest low tides, occur when the Sun, Moon and Earth line up at full and new moon, and neap tides, with a smaller range, occur when they are at right angles. The tidal range varies widely, and the Bay of Fundy has one of the largest. Tides are used for energy, and they affect shipping, fishing and coastal ecosystems.

How the interactive helps you understand Tides

Watch the Earth model in the interactive. Use any sliders or buttons it offers to change the values and see how the Earth model responds.

Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Tides.

Real-life uses and examples

• Explain how Tides affects people, jobs and land use in a region.
• Support an answer about Tides with a named case study and specific evidence.
• Interpret a graph or map that shows Tides and say what it suggests.

Common mistakes to avoid

• Mixing up cause, effect and consequence when you explain Tides.
• Writing general statements without a named place or example.
• Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.