What is the only ocean that completely surrounds Antarctica?

The Southern Ocean is the ocean that completely surrounds Antarctica.

Also called the Antarctic Ocean, it encircles the continent and links the southern parts of the Atlantic, Indian, and Pacific oceans. Its northern boundary is commonly defined by the Antarctic Circumpolar Current, which flows from west to east around Antarctica and is the world’s largest ocean current.

The Southern Ocean is especially important to global climate. Cold Antarctic water sinks and contributes to deep-ocean circulation, while the current helps isolate Antarctica from warmer waters at lower latitudes. The region also supports ecosystems that include krill, penguins, seals, and whales.

Geographers and organizations have not always agreed on its exact boundaries or status. The International Hydrographic Organization proposed limits in 2000, and National Geographic recognized it as the world’s fifth ocean in 2021. Earlier maps often divided these waters among the Atlantic, Indian, and Pacific oceans instead of naming a separate ocean.