If you had to draw the boundaries of the Earth's oceans on a map, would you be able to? The answer is no—because there is really only one "world ocean." Oceanographers have divided the world ocean into four principal areas, or basins: the Pacific, Atlantic, Indian, and Arctic Ocean basins. The Atlantic, Indian, and Pacific Ocean basins merge into icy waters around Antarctica. Some oceanographers define this as a fifth ocean, usually called the Antarctic or Southern Ocean basin.


This video focuses on the Indian Ocean basin and is taken from the interactive online game, My Ocean. Test your ocean knowledge and learn about the different basins of the world ocean by playing here.

  • The Indian Ocean is nearly six times the size of the United States and spans over 9,978 kilometers (6,200 miles) from the southern tip of Africa to the western coast of Australia.
  • The deepest point in the Indian Ocean is the Java Trench. The Java Trench is also referred to as the Sunda Trench.
  • Oil tankers on the Indian Ocean carry 17 million barrels of crude oil a day from the Persian Gulf en route to shipping ports around the world.
  • The Indian Ocean is the warmest ocean basin on earth. The warmth of the water inhibits the growth of phytoplankton and severely limits the amount of marine animals this area of the ocean can support.
  • During the winter, humpback whales travel from cold waters near the poles, where they spend the summer feeding, toward warmer waters closer to the equator. It's estimated that each year, 7,000 humpback whales migrate to the waters around Madagascar to breed and calve.

study and investigation of unknown places, concepts, or issues.

Indian Ocean

one of Earth's four oceans, bordered by Africa, Asia, Australia, and Antarctica.


having to do with the ocean.


large body of salt water that covers most of the Earth.