requently are 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 Centigrade; at some coastal points intense persistent
drainage winds from the interior keep the shoreline ice-free
throughout the winter

Terrain: the Southern Ocean is deep, 4,000 to 5,000 meters over most
of its extent with only limited areas of shallow water; the antarctic
continental shelf is generally narrow and unusually deep - its edge
lying at depths of 400 to 800 meters (the global mean is 133 meters);
the Antarctic ice pack grows from an average minimum of 2.6 million
square kilometers in March to about 18.8 million square kilometers in
September, better than a sevenfold increase in area; the Antarctic
Circumpolar Current (21,000 km in length) moves perpetually eastward;
it is the world's largest ocean current, transporting 130 million
cubic meters of water per second - 100 times the flow of all the
world's rivers

Elevation extremes:
lowest point: -7,235 m at the southern end of the South Sandwich
Trench
highest point: sea level 0 m

Natural resources: probable large and possible giant oil and gas
fields on the continental margin, manganese nodules, possible placer
deposits, sand and gravel, fresh water as icebergs, squid, whales, and
seals - none exploited; krill, fishes

Natural hazards: huge icebergs with drafts up to several hundred
meters; smaller bergs and iceberg fragments; sea ice (generally 0.5 to
1 meter thick) with sometimes dynamic short-term variations and with
large annual and interannual variations; deep continental shelf
floored by glacial deposits varying widely over short distances; high
winds and large waves much of the year; ship icing, especially
May-October; most of region is remote from sources of search and
rescue

Environment - current issues: increased solar ultraviolet radiation
resulting from the antarctic ozone hole in recent years, reducing
marine primary productivity (phytoplankton) by as much as 15% and
damaging the DNA of some fish; illegal, unreported, and unregulated
fishing in recent years, especially the landing of an estimated five
to six times more Patagonian toothfi