Southern Ocean Southern Ocean The Southern Ocean, also known as the Antarctic Ocean or the Austral Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. As such, it is regarded as the fourth-largest of the five principal oceanic divisions: smaller than the Pacific, Atlantic, and Indian Oceans but larger than the Arctic Ocean. This ocean zone is where cold, northward flowing waters from the Antarctic mix with warmer subantarctic waters. By way of his voyages in the 1770s, Captain James Cook proved that waters encompassed the southern latitudes of the
World Ocean Ocean, and Southern Ocean, defined by the International Hydrographic Organization (IHO) in 2000, based on evidence that this region of the World Ocean has a distinct ecosystem and a unique impact on global climate. In turn, oceanic waters are interspersed by many smaller seas, gulfs, and bays. A global ocean has existed in one form or another on Earth for eons, and the notion dates back to classical antiquity in the form of Oceanus. The contemporary concept of the "World Ocean" was coined in the early 20th century by the Russian oceanographer Yuly Shokalsky to refer to the continuous ocean