Extending from Antarctica to 60 degrees south latitude, the Southern Ocean features the Antarctic Circumpolar Current—the largest ocean current on Earth—which encircles Antarctica and creates a unique biogeographical zone.

While viral videos have claimed to show boundaries where oceans do not mix, Earth's oceans do mix, though differences in salinity, temperature, and density can cause this process to occur very slowly.

The Atlantic Ocean was named after Atlas, who was sentenced by Zeus in Greek mythology to hold up the sky, while the Pacific Ocean was named by Ferdinand Magellan as the 'peaceful sea' in 1520.

A simple pictorial explanation of ocean geography

Visualizing ocean geographical features, such as a coastal zone, continental shelf and abyssal plain. This article from the US Geological Survey also provides several links to diverse ocean facts.

Research suggests that the Antarctic Circumpolar Current—Earth's most powerful ocean current, which carries over 100 times the combined water of all of Earth's rivers—formed about 34 million years ago.

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 that create vertical circulation.

The top several meters of the world's oceans can hold as much thermal energy as the entire atmosphere, and their average surface temperature has increased by 0.9 degrees Celsius (1.62 degrees Fahrenheit) since the pre-industrial era.

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.

Watch a visualization of global ocean currents from NASA's Estimating the Circulation and Climate of the Ocean project, which incorporates hundreds of millions of data points from satellites and floating sensors.

The world's oceans, which have an average depth of 3.7 kilometers (2.3 miles), are often vertically divided into five zones based on depth or three zones based on the abundance of light.

What's the difference between an ocean, sea, and saltwater lake?

What are the seven seas, the five oceans, and why isn't the Dead Sea considered a sea? This overview provides definitions for each.

American oceanographic cartographer Marie Tharp's discovery of the Mid-Atlantic Ridge, which supported the idea that continents move over time, was initially dismissed as 'girl talk.'

No map of the Earth is perfect because each introduces inaccuracies in the shape, size, or orientation of landmasses and oceans by trying to flatten the planet's curved surface.

The US Board on Geographic Names is responsible for ensuring uniform usage of geographic names within the government.

Around 380 underwater cables power the Internet across the world.

On July 29, 1858, two steam-powered battleships met in the middle of the Atlantic Ocean. There, they connected two ends of a 4,000 kilometer (2,500 mile) long, 1.5 centimeter (0.6 inch) wide cable, linking for the first time the European and North American continents by telegraph.

The Ocean Observatories Initiative aims to provide freely accessible, real-time ocean data for up to 30 years to help scientists identify and analyze short- and long-term ocean processes.

Null Island is located at a latitude and longitude of 0°

A buoy denotes the fictional island where the Prime Meridian intersects with the equator in the Atlantic Ocean. Nations had disagreed on where the "origin" of world maps should be located until the Prime Meridian and Greenwich Mean Time were established in 1884.

The history of deep-sea mining and its governance by the International Seabed Authority

The British HMS Challenger research vessel identified metal-rich seafloor rocks between Hawaii and Mexico in the 1870s, but rules governing which nations control which parts of the ocean were not established until 1958 by the UN. It later established the ISA to oversee mineral-related operations in international waters.

Mapping the route options between the Pacific and Atlantic

This map shows some of the alternative trade route options that are available to shipping companies, from overland routes that rely on railways to transport goods coast-to-coast, to Arctic Ocean passages.

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 history of the world map

What did people used to think the world looked like? From the beginning of human history to right before the age of exploration, learn how the world maps were created.

How the ocean is the new frontier of innovation

Space has been called the final frontier of innovation and investment for decades. Many innovators say the ocean is the new space, the vast majority of whose hidden depths remain obscure. In this podcast episode, business-minded experts discuss the opportunities founders see in the ocean, including seagrass restoration, underwater cable networks, and more.

Visualizing changes in ocean temperatures between 2016 and 2020

How much does the temperature of the sea change in a given year? This visualization helps illustrate the changes by showing sea surface temperature data from January 2016 through March 2020. Sea surface temperature, which refers to water temperature at the sea's surface, plays a significant role in climate and weather.

Tropical cyclones are called hurricanes, typhoons, and cyclones around the world

Tropical cyclones are named differently based on their region of origin due to historical traditions and cultural importance. These storms are called hurricanes in the Atlantic and northeast Pacific oceans, cyclones in the southwest Pacific and Indian oceans, and typhoons in the northwest Pacific Ocean.

Learn about various ocean-atmosphere cycles impacting global weather patterns

Although the El Niño-Southern Oscillation is among the most impactful, the North Atlantic Oscillation strongly influences weather patterns in the Northeast US by periodically changing atmospheric pressure over the Atlantic. The North Pacific Oscillation fluctuates atmospheric pressure and sea-surface temperatures that affect winter temperatures over much of the US.

Scientists determined that tectonic plates moved the ocean floor by observing symmetric patterns of magnetic stripes on opposite sides of underwater volcano systems, which could only result from seafloor spreading.

National Geographic presents how to protect the oceans

What can we do to protect and preserve the world's oceans? Be inspired by spectacular wildlife footage from National Geographic while learning key strategies.

The Rodinia supercontinent triggered a global ice age when it broke 750 million years ago

Before Pangaea, the Earth’s continental plates had drifted together and broken apart multiple times, with each event altering atmospheric CO2 concentrations and triggering climate change. The continents are estimated to come together again in 50 million to 250 million years.

The world's quirkiest time zones

In contrast to telling time by physical signs like the sun or stars, cultural time relies on political agreement and standards. The convention of time zones arose due to transportation and communication advancements, and while many work just fine, some are pretty wild. Chief among those is the time zone of the uninhabited Baker and Howland Islands in the central Pacific, which results in a technical 26-hour day.

Railroads and long-distance communication led to the development of time zones, with Greenwich established as the prime meridian—the longitude of 0 degrees—due to British advancements in star mapping and navigation.