Geography
What are the oceans of the world?
Quick answer
Oceans are the huge bodies of salt water that cover most of Earth. There are five: the Pacific, Atlantic, Indian, Southern and Arctic.
In one sentence
An ocean is one of the five enormous areas of salt water that cover most of our planet.
Explained
About 71% of Earth's surface is ocean, which is why Earth looks blue from space. All the oceans are joined together, so really there is one world ocean. People split it into five named parts to make it easier to talk about and map.
From largest to smallest, the five oceans are the Pacific, Atlantic, Indian, Southern and Arctic. The Pacific is so big that all the continents could fit inside it. Its Mariana Trench is about 11 kilometres deep, deeper than Mount Everest is tall.
For a long time, many maps showed only four oceans. The waters around Antarctica were treated as the southern ends of the Pacific, Atlantic and Indian Oceans. Scientists noticed that this cold water behaves differently, flowing in a strong current right round Antarctica. Many organisations now name it the Southern Ocean, and National Geographic added it to its maps in 2021. Not every organisation has made it official yet, so you might still see four oceans in older books.
Seas are smaller parts of the ocean, usually partly surrounded by land, such as the Mediterranean Sea or the Caribbean Sea. Oceans matter to everyone: they give us food, carry ships, and help control the weather through the water cycle.
Examples
| Ocean | Where it is | A country on its coast |
|---|---|---|
| Pacific | between Asia, Australia and the Americas | Japan |
| Atlantic | between the Americas, Europe and Africa | Nigeria |
| Indian | south of Asia, east of Africa | India |
| Southern | around Antarctica | none (only Antarctica) |
| Arctic | around the North Pole | Canada |
Common mistakes
- "The Atlantic is the biggest ocean." It is second. The Pacific is much larger.
- Calling a sea an ocean. The Mediterranean and the Red Sea are seas, not oceans.
- Thinking oceans are separate pools. They are all connected; the borders between them are lines people agreed on.
Quick quiz
Oceans
Check what you know with 4 quick questions.
Question 1 of 4
Which is the largest and deepest ocean?
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Map the oceans and continents
For grown-ups
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