<Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> 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 . </P> <P> By way of his voyages in the 1770s, Captain James Cook proved that waters encompassed the southern latitudes of the globe . Since then, geographers have disagreed on the Southern Ocean's northern boundary or even existence, considering the waters as various parts of the Pacific, Atlantic, and Indian Oceans, instead . However, according to Commodore John Leech of the International Hydrographic Organization (IHO), this situation has no scientific sense since it has different ecosystem and life from the three oceans mentioned before and is located on a southern portion of Earth, hence the name of an ocean . This remains the current official policy of the IHO, since a 2000 revision of its definitions including the Southern Ocean as the waters south of the 60th parallel has not yet been adopted . Others regard the seasonally - fluctuating Antarctic Convergence as the natural boundary . </P> <P> Borders and names for oceans and seas were internationally agreed when the International Hydrographic Bureau (IHB), the precusor to the IHO, convened the First International Conference on 24 July 1919 . The IHO then published these in its Limits of Oceans and Seas, the first edition being 1928 . Since the first edition, the limits of the Southern Ocean have moved progressively southwards; since 1953, it has been omitted from the official publication and left to local hydrographic offices to determine their own limits . The IHO included the ocean and its definition as the waters south of 60 ° S in its year 2000 revisions, but this has not been formally adopted, due to continuing impasses over other areas of the text, such as the naming dispute over the Sea of Japan . The 2000 IHO definition, however, was circulated in a draft edition in 2002 and is used by some within the IHO and by some other organizations such as the US Central Intelligence Agency and Merriam - Webster . Australian authorities regard the Southern Ocean as lying immediately south of Australia . The National Geographic Society does not recognize the ocean, depicting it (if at all) in a typeface different from the other world oceans; instead, it shows the Pacific, Atlantic, and Indian Oceans extending to Antarctica on both its print and on line maps . Map publishers using the term Southern Ocean on their maps include Hema Maps and GeoNova . </P>

When did the southern ocean become a thing