The Southern Ocean features the Antarctic Circumpolar Current—the largest ocean current on Earth—which encircles Antarctica and creates a unique biogeographical zone.

The Antarctic Circumpolar Current is Earth's most powerful ocean current and carries more than 100 times the combined flow of all Earth's rivers.

Just as landmasses have been divided into distinct nations, the world ocean has been divided into multiple oceans for various geographical, practical, and scientific reasons.

Surface ocean currents are primarily driven by wind, tides, and Earth's rotation, while deep-ocean currents are driven by differences in temperature and salt concentration.

View a gallery of animals found on abyssal plains, hydrothermal vents, seamounts, and other deep-sea habitats.

What we know about the mysterious colossal squid

The colossal squid, the world's largest invertebrate, remained hidden from human discovery until nearly a century ago. Explore the world of the enormous and mysterious creature, including its features, habitat, and scientific significance. You can even plan a visit to the Museum of New Zealand Te Papa Tongarewa and marvel at a real-life display.

Visualizing the 75 largest underwater animals

With so many fish in the sea, which are the largest? This infographic shows fantastic illustrations of the 75 largest sea animals, ranked by average size. The detailed visual is organized in descending order of size, starting with the blue whale,...

Studying the circadian clock of a tiny swimming polar creature may help forecast polar ecosystem health

A 2025 study found that Antarctic krill, a food chain staple in the Southern Ocean, have an internal biological clock that helps regulate its swimming patterns and helps the tiny shrimp-like animals adapt to daily and seasonal environmental changes. Better understanding of how the clock and light cues interact may help scientists understand how well the species will respond to pronounced climate change in the polar region.

The deep-sea fangtooth has the largest teeth of any marine species relative to body size

From transparent fish to the heaviest worms on the planet, these seven creepy creatures lurk in the deep sea. Learn all about them and the unique traits that help them survive and hunt.

Search for psychrotolerant and psychrophilic microorganisms found in Antarctica

Developed following a five-week expedition to the southern continent, "Life Under the Ice" allows users to examine a petri-dish-like microscopic world and uncover recordings of organisms that can withstand, or even thrive, in the harsh environment.

What animals live in the ocean?

The oceans host an incredible diversity of fascinating species. Oceana's Marine Life Encyclopedia beautifully presents facts and photos of ocean animals from Atlantic Cod to Zebra Sharks.

Watch a visualization of global ocean currents from NASA's Estimating the Circulation and Climate of the Ocean project.

Earth's oceans, which have an average depth of 3.7 kilometers (2.3 miles), may be divided into zones based on depth or the abundance of light.

The British Antarctic Survey created a map of what Antarctica would look like if it lost all 27 million cubic kilometers (6.5 million cubic miles) of its ice—enough to fill almost 6,500 Grand Canyons.

The robust wine production of Antarctica

Antarctica might not be known for its agriculture, but parts of its unique climate are suitable for growing wine grapes. Most of the wine produced there is icewine, a style of dessert wine commonly found in Canada and Germany. This guide covers Antarctica’s unique soil composition, grape varieties, and how exactly penguins contribute to this unusual wine-growing region. There’s even a recommendation for an Antarctic tasting room for adventurous souls.

The world's largest deserts—areas that receive less than 10 inches of annual rainfall—are led by the Antarctic and Arctic regions.

Why the Antarctic climate enabled British scientists to discover the ozone hole

In the Antarctic stratosphere, polar conditions facilitate the formation of polar stratospheric clouds, which allow chlorine compounds from chlorofluorocarbons to accumulate. In 1985, British Antarctic Survey scientists detected massive springtime losses over Antarctica, as accumulated compounds destroyed significant amounts of ozone once sunlight returned.

The top several meters of the world's oceans can hold as much thermal energy as the entire atmosphere.

How salt, sunlight, and wind drive ocean currents

The Atlantic Meridional Overturning Circulation plays a critical role in regulating earth's climate, but is threatened by climate change. Explore the effects of temperature, density, and salinity on ocean currents in this 13-minute PBS video.

The 10 most amazing deep sea creatures

In this video, researchers from the world-renowned Monterey Bay Aquarium discuss the most fascinating deep sea creatures, and how they developed some of their strangest features.

How glaciers melt

Greenland and Antarctica are home to most of the world's glacial ice, including its only two ice sheets, making them areas of particular interest to scientists. Watch this three-minute video to learn why understanding them is not just interesting, but crucial to our near-term adaptability and our long term survival in a changing world.

Explore the history, structure, and species of Australia's Great Barrier Reef with this interactive journey narrated by Sir David Attenborough.

Can coral live in cold water?

Dive deep beyond the sunlit coral reefs, and you'll discover a world of deep-sea corals. This article from the National Oceanic and Atmospheric Administration (NOAA) explores the ecosystems of deep-sea corals found way below the water's surface....

Although an estimated 99.999% of the deep ocean has not been explored, techniques such as sonar have been used to identify the deepest known point in each of Earth's five oceans.

The world's largest species of marine algae is giant kelp, which can grow as much as two feet per day from depths of about 100 feet up to the ocean surface.

The ocean's ability to store carbon long-term is being hindered by marine heatwaves

More than 4,000 robotic floats with biogeochemical data sensors, including oxygen, pH, nitrate, suspended particles, chlorophyll, temperature, and conductivity, have been deployed as part of the Global Ocean Biogeochemical Array. They have identified changes to ecosystem structure affecting the ocean's ability to transport carbon from surface waters into the deep.

Deep Blue is the largest great white shark ever caught on camera

In 2019, Deep Blue was one of three huge great whites spotted off the coast of Oahu, Hawaii, an uncommon place for sightings of white sharks. The unique series of sightings aroused curiosity and amazement from islanders and scientists alike.

Some marine life can survive the extreme pressure of the deep ocean because of specialized molecules that strengthen proteins, enzymes, and cellular membranes.

Whale falls—dead whales that have fallen to the ocean's floor—can provide enough food to spawn a local ecosystem of deep-sea organisms that lasts for decades.

The warmest waters in the ocean are found at hydrothermal vents—hot springs on the seafloor that discharge plumes of mineral-rich water.

Located in the Pacific Ocean, the Challenger Deep is the deepest point on Earth, extending to depths a mile deeper than Mount Everest is tall.

Take an interactive dive and see the animals that populate the oceans, from coral near the surface to shrimp-like organisms near the seafloor.

As of 2026, the Great Atlantic Sargassum Belt is the world's largest macroalgal bloom, with seaweed stretching from the Caribbean to West Africa.

The world's largest coral, as seen from space

The world’s largest individual coral colony—measuring over 100 feet wide and 100 feet long—was discovered in the Solomon Islands. This coral is so large it can be seen from space, and is estimated to be between 300 and 500 years old. The coral's size and health provide hope amidst a global coral bleaching crisis, wherein three-quarters of coral reefs have experienced significant bleaching in recent decades. See the photos from space and learn more here.

Deep water corals—located throughout the world's ocean basins at depths beyond 200 meters (660 feet)—slowly build small coral gardens in the dark with the help of underwater worms.

The Atlantic Ocean was named after Atlas, who holds up the sky in Greek mythology, while the Pacific Ocean was named by Ferdinand Magellan.

Scientists have found that the Great Barrier Reef's microbiome includes an estimated 362,802 distinct viruses and 876 distinct bacterial and archaeal species—584 of which had never been documented before 2026.

An interactive of the deep sea

Fish in polar waters contain proteins in their blood that act as antifreeze, and some manufacturers have used lab-grown versions of these proteins to help keep ice cream smooth.

The South American lungfish has the largest known animal genome, with 91 billion base pairs—a set of genetic instructions about 30 times larger than a human's.

Over 1 million fish, marine mammals, and invertebrate species depend on coral reefs for habitats, camouflage, and food.

What happens when a whale dies and falls to the ocean floor

A large whale's body can blanket more than 538 square feet of ocean floor. That's an enormous amount of organic matter, providing food for the ecosystem for centuries. Researchers have discovered bones on the seafloor from whale species that have been extinct for over 100,000 years.

Take a virtual tour of the Royal Research Ship named after David Attenborough

Operated by the British Antarctic Survey, the RRS Sir David Attenborough and its onboard tools and laboratories have investigated the biogeochemical cycles of the Southern Ocean, the stability of Greenland's ice shelves, and the impact of climate change on marine ecosystems. One of the ship's autonomous underwater vehicles was named Boaty McBoatface based on the results of a naming poll from the Natural Environment Research Council.

Explore the deepest parts of the ocean

The deeps of the Earth's oceans are some of the most extreme environments on the planet. Take a trip 36,000 feet to the deepest parts of the sea in this informative, 10-minute animated video.

Earth's oceans do mix, despite viral images and videos claiming to show boundaries between oceans that waters do not cross.

38 thought-provoking facts about the ocean

Coral produces its own sunscreen, tsunamis move at 500 miles per hour, one of the loudest sounds ever recorded came from an ice quake, and other interesting facts collected from sources such as National Geographic and NASA.

Supermountains the size of the continental US may have sparked complex life on Earth

Geological records show that the Nuna and the Transgondwanan Supermountains existed around the same time as two major jumps in species complexity on the planet: the rise of large organisms and the Cambrian explosion, respectively. Researchers believe that the erosion of these mountains deposited major nutrients into the oceans and boosted oxygen levels, both of which supported more complex species.

The biggest ocean waves in the world, which regularly reach between 80 and 100 feet, are primarily caused by a 140-mile-long submarine canyon that reaches a maximum depth of 16,000 feet.

Why no aquarium has a great white shark

Historically, great white sharks die very quickly in captivity—with the exception of the Monterey Bay Aquarium's successful attempt in 2004. The aquarium held a four-year-old great white for six months. Before that, the longest stint was 16 days. The creatures can only breathe if they are moving forward, making survival difficult in a small tank.

Track the current size of the Antarctic ozone hole with NASA's real-time data

NASA's Ozone Watch provides daily satellite images and time-lapse videos showing the extent of the Antarctic ozone hole. Each spring, scientists monitor its size and depth to measure recovery progress and detect any new chemical or climatic disruptions.

While nearly all fish are cold-blooded—their body temperatures match their surroundings—the opah, or moonfish, is fully warm-blooded, with a body temperature about 5 degrees Celsius (9 degrees Fahrenheit) warmer than its environment.