Oceans
Dive into the vast blue expanses that cover most of our planet, home to countless species and vital to Earth's climate systems.
Earth's Surface
71%
Covered by oceans
Ocean Volume
1.335B
Cubic kilometers
Average Depth
3,688m
About 12,100 feet
Known Species
230K+
Marine species
The World Ocean
While we name five distinct oceans, they're all connected as one global ocean system. This 'World Ocean' circulates water, heat, and nutrients around the planet, regulating climate and supporting life. Ocean currents act like a global conveyor belt, moving warm water from the equator toward the poles and cold water back. This circulation affects weather patterns, supports fisheries, and stores enormous amounts of carbon dioxide.
Ocean Exploration
Despite covering 71% of Earth's surface, more than 80% of the ocean remains unmapped and unexplored. We've explored more of Mars and the Moon than our own ocean floor. The deep sea presents extreme challenges: crushing pressure, complete darkness, and near-freezing temperatures. Yet every expedition reveals new species and geological wonders, from bioluminescent creatures to hydrothermal vents teeming with life.
The Five Oceans
Pacific Ocean
The largest and deepest ocean, covering more than 30% of Earth's surface—larger than all landmasses combined. Named by explorer Ferdinand Magellan for its calm waters, the Pacific contains the Ring of Fire, home to 75% of the world's volcanoes and 90% of earthquakes.
Notable Features
- Mariana Trench (deepest point)
- Great Pacific Garbage Patch
- Coral Triangle
- Over 25,000 islands
Atlantic Ocean
The second-largest ocean, separating the Americas from Europe and Africa. It formed when the supercontinent Pangaea broke apart about 180 million years ago. The Atlantic has been crucial for trade and exploration, hosting routes between the Old and New Worlds.
Notable Features
- Mid-Atlantic Ridge
- Gulf Stream current
- Sargasso Sea
- Bermuda Triangle
Indian Ocean
The third-largest ocean, bounded by Asia, Africa, and Australia. It's the warmest ocean and has been a crucial maritime trade route for millennia, connecting ancient civilizations through the spice trade and Silk Road maritime routes.
Notable Features
- Monsoon systems
- Madagascar biodiversity
- Maldives coral atolls
- Arabian Sea
Southern Ocean
The youngest ocean, officially recognized in 2000, encircling Antarctica. It's defined by the Antarctic Circumpolar Current—the world's largest ocean current. These frigid waters support unique ecosystems including krill populations that feed whales, seals, and penguins.
Notable Features
- Antarctic Circumpolar Current
- Krill populations
- Sea ice dynamics
- Whale feeding grounds
Arctic Ocean
The smallest and shallowest ocean, located around the North Pole. Much of it is covered by sea ice, though climate change is rapidly reducing ice coverage. Indigenous peoples have lived along its coasts for thousands of years, and it's becoming increasingly important for shipping routes.
Notable Features
- Polar ice cap
- Northern Lights visibility
- Indigenous Arctic cultures
- Northwest Passage
Ocean Conservation
Our oceans face unprecedented threats from climate change, pollution, overfishing, and habitat destruction. Rising temperatures cause coral bleaching, ocean acidification harms shellfish, and plastic pollution reaches even the deepest trenches. Marine protected areas, sustainable fishing practices, and reducing carbon emissions are critical for preserving ocean health. The ocean absorbs about 30% of human-produced CO2 and over 90% of excess heat from global warming—protecting it means protecting ourselves.