ocean: Quick Facts

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Facts

Also Known As	world ocean

Photos and Videos

Map graphic showing the boundaries of the five oceans-Pacific, Atlantic, Indian, Arctic, and Southern-using color-coded regions. Four different map projections are included: North Pole view, South Pole view, International Date Line view, and Greenwich Meridian view, each displaying the oceans' extents around the continents.

Diagram showing ocean zonation by depth and region, with labeled layers: littoral, sublittoral, bathyal, abyssal, and hadal along the seafloor, and epipelagic, mesopelagic, bathypelagic, and abyssalpelagic in open water. The littoral zone is at the high-tide mark. Vertical scale marks photic and aphotic zones from surface to 10,000 meters.

World map highlighting major features of the ocean basins, including trenches, ridges, basins, and plateaus labeled throughout the Pacific, Atlantic, Indian, Southern, and Arctic Oceans. Continents are shown with shaded terrain, and prominent undersea features such as the Mid-Atlantic Ridge, Mariana Trench, and Kerguelen Plateau are marked across the map.

Diagram of the water cycle showing processes like evaporation, condensation, precipitation, transpiration, infiltration, and groundwater flow between land, vegetation, surface water, and the ocean, with labeled arrows and color-coded soil moisture and groundwater zones.

World map displaying the boundaries of major oceans and seas, each labeled with a number corresponding to a list below the map. The map uses simple blue and tan color coding for water and land, with numbered points marking locations such as the Mediterranean Sea, Gulf of Mexico, South China Sea, and others. A locator inset and scale are included for reference.

hypsographic curve

Diagram showing the transition from land to deep ocean, with labeled features including coastal plain, shoreline, continental shelf, continental slope, submarine canyon, seamounts, continental rise, and abyssal plain, illustrating the structure of the continental margin.

Global sea level change

$Map of the Pacific Ocean showing the age of selected regions of the seafloor, with color-coded bands representing different geological ages from Cretaceous (136 million years ago) to Pleistocene (0 million years ago). The map highlights mid-ocean ridges, deep ocean trenches, and fracture zones, with arrows indicating the direction of crustal plate spreading. Major trenches such as the Mariana, Peru-Chile, and Aleutian Trenches are labeled.$

Hear researcher Andy Wheeler speaking about an expedition to discover new hydrothermal vent field in the middle of the Atlantic Ocean

Discover how individuals can change their habits of consumption and disposal of single-use products, especially plastics, to keep trash out of the ocean

Satellite image showing three labeled hurricanes—Florence, Isaac, and Helene—across the Atlantic Ocean in September 2018.

Learn about the water cycle and how oceans act as the Earth's water reservoirs

The importance of Wadden Sea tidal flats for migrating birds

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Topics

iceberg ocean current ocean basin sea ice furious fifties submarine landform marine ice fast ice ocean-atmosphere interaction drift ice river lake Harbors and sea works cave continental landform Wetland lagoon gulf bay spring

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Key People

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Addison Emery Verrill

American zoologist

The map that changed the world

Marie Tharp

American oceanographer and cartographer

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Charles William Peach

English naturalist and geologist

C. Wyville Thomson, 1877.

Sir C. Wyville Thomson

Scottish naturalist

1:116 Aquanauts: Underwater Treasure, divers searching for treasure underwater

International Waters

wave. ocean. Cresting ocean wave. Large sea waves. storm, hurricane, tropical cyclone

All About Oceans and Seas Quiz

13 True-or-False Questions from Britannica’s Easiest Science Quizzes

water glass on white background. (drink; clear; clean water; liquid)

Water and its Varying Forms

Mediterranean sea and aerial view of Antalya, Turkey.

Earth’s Seas

Metal and enamel pan of boiling water on stove. (boiling point; cooking; steam; cooking gas; non-electric)

Aitch-Two-Oh?

Chutes d'Ekom - a waterfall on the Nkam river in the rainforest near Melong, in the western highlands of Cameroon in Africa.

Ecosystems

Cross section of Earth showing the core, mantle, and crust

Everything Earth