The
Southern Ocean (also known as the Great Southern Ocean, Antarctic
Ocean, South Polar Ocean, and 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 (after 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.
Geographers
disagree on the Southern Ocean's northern boundary, and some even
its existence—considering the waters part of the Pacific, Atlantic,
and Indian Oceans instead. Others regard the Antarctic Convergence,
an ocean zone which fluctuates seasonally, as separating the Southern
Ocean from other oceans, rather than the 60th parallel. Australian
authorities regard the Southern Ocean as lying immediately south
of Australia.
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