SOUTHERN OCEAN
The Southern Ocean, designated as such in 2000, is a body of water that lies between 60 degrees south latitude and the Antarctica coastline. It's coordinates nominally are 65 00 S, 0 00 E, but the Southern Ocean has the unique distinction of being a large circumpolar body of water totally encircling the continent of Antarctica. This ring of water lies between 60 degrees south latitude and the coast of Antarctica, and encompasses 360 degrees of longitude. The Southern Ocean is now the fourth largest of the world's five oceans (after the Pacific Ocean, Atlantic Ocean, and Indian Ocean, but larger than the Arctic Ocean).
Some of the current issues include - impacts of global warming, ocean currents, environment and climate change research, fisheries.
The Southern Ocean, also known as the Great Southern Ocean, the Antarctic Ocean and the South Polar Ocean, comprises the southernmost waters of the World Ocean south of 60 degree S latitude. The International Hydro graphic Organization has designated the Southern Ocean as an Oceanic division encircling Antarctica. Geographers disagree on the southern Ocean’s northern boundary or even its existence, sometimes considering the waters part of the South Pacific, South Atlantic, and Indian Oceans instead.
Some scientists consider the Antarctic Convergence, an ocean zone which fluctuates seasonally, as separating the Southern Ocean from other oceans, rather than 60 degree S. This ocean zone is where cold, northward flowing waters from the Antarctic mix with warmer sub-Antarctic waters.
The International Hydro graphic Organization (IHO) regards the Southern Ocean as the fourth-largest of the five principal oceanic divisions and the latest-defined one. The IHO promulgated the decision on its existence in 200, though many mariners have long regarded the term as traditional. The Southern Ocean appeared in the IHO’s Limits of Oceans and Seas second edition (1937), disappeared from the third edition (1957), and re-surfaced in the fourth edition (not yet formally adopted due to a number of unresolved disputes, including the lodgement of a reservation by Australia). This change reflects the Importance placed by oceanographers on ocean currents.
GEOGRAPHY:
The Southern Ocean includes the Antarctic Circumpolar Current (which circulates around Antarctica) the Amundsen Sea, Bellingshausen Sea, parts of the Drake Passage, Ross Sea, Cooperation Sea, the Cosmonaut Sea, a small part of the Scotia Sea, and Weddell Sea. Its total area comprises 20,327,000 square kilometers (7,848,000 mi²).
The Southern Ocean differs from the other oceans in that its largest boundary, the northern boundary, does not abut any landmass, but merges into the Atlantic, Indian and Pacific Oceans. This calls into question why geographers should consider the Southern Ocean a separate ocean, as opposed to a southward extension of the other three oceans. One reason stems from the fact that much of the water of the Southern Ocean differs from the water in the other oceans. Because of the Antarctic Circumpolar Current, that water gets transported around the Southern Ocean fairly rapidly, so that the water in the Southern Ocean south of, for example, South America, resembles the water in the Southern Ocean south of New Zealand more closely than it resembles the water in the mid-Indian Ocean.
Several processes operate along the coast of Antarctica to produce, in the Southern Ocean, types of water masses not produced elsewhere in the oceans of the Southern Hemisphere. One of these is the Antarctic Bottom Water, a very cold, highly saline, dense water that forms under sea ice.
The Southern Ocean, geologically the youngest of the oceans, formed when Antarctica and South America moved apart, opening the Drake Passage, roughly 30 million years ago. The separation of the continents allowed the formation of the Antarctic Circumpolar Current.
In many respects, the Southern Ocean forms the opposite of the Arctic Ocean, located on the opposite end of the globe.
Arctic and Southern Oceans contrasted
Arctic Ocean Southern Ocean
Surrounded by Eurasia and North America Encircles the Antarctic continent
Warm ocean moderates frigid land Icy landmass feeds cold ocean
Freshwater from rivers feeds the Arctic Ocean The melting of glaciers feeds the Southern
Ice forms at very center of the Arctic Ice forms along the Antarctic coastline
HISTORY:
The second edition (1937) of the IHO's Limits of Oceans and Seas included the Southern Ocean; however, it did not appear in the third edition (1953) because of the fluctuation of its northern hydrographic limits with the seasons and because scientists felt that an ocean should be defined as "water surrounded by land" not "water encircling land". Individual member states' hydrographic offices have defined their own boundaries; the United Kingdom used the 55°S parallel.
The IHO readdressed the question in a survey in 2000. Of the 68 member nations, 28 responded, and all responding members except Argentina agreed to define a new ocean. The proposal for the name Southern Ocean won 18 votes, beating the alternative Antarctic Ocean. Half of the votes supported ending the ocean at the 60 degrees south line of latitude (with no land interruptions at this latitude), with the other 14 votes cast for other definitions, mostly 50 degrees south, but a few for as far north as 35 degrees south.
Other sources such as the National Geographic Society continue to show the Atlantic, Pacific and Indian Oceans as extending to Antarctica.
In Australia, cartographical authorities defined the Southern Ocean as including the entire body of water between Antarctica and the south coasts of Australia and New Zealand, although New Zealand authorities do not generally follow suit. Coastal maps of Tasmania and South Australia label the sea areas as Southern Ocean, while Cape Leeuwin in Western Australia is described as the point where the Indian and Southern Oceans meet.
CLIMATE:
Sea-temperatures vary from about – 2 to 10 degree C (28 to 50 degree F). Cyclonic storms travel eastward around the continent and frequently become intense because of the temperature-contrast between ice and open ocean. The ocean-area from about latitude 40 south to the Antarctic Circle has the strongest average winds found anywhere on Earth. In winter the ocean freezes outward to 65 degrees south latitude in the Pacific sector and 55 degrees south latitude in the Atlantic sector, lowering surface temperatures well below 0 degrees Celsius; at some coastal points intense persistent drainage winds from the interior keep the shoreline ice-free throughout the winter.
