Page 204 - NS-2 Textbook

MARITIME GEOGRAPHY 199

The continent of Antarctica. The continent is completely surrounded by the waters of the Atlantic, Pacific, and Indian Oceans and by the Ross
and Weddell Seas.

they total about 13.5 million square miles. More than
half, about 8 million square lniles, freezes over each vvin-
tel~ and 1.5 million square miles are frozen year around.
The water and ice boundaries are determined by
water movement. There is a rather ,vell-defined zone in
which southward-flowing '\",ann 'water rises over the col-
umn of cold Antarctic waters flowing northward. The
cold-water portion of the water cohUlm is called the polar
front, and the warmer surface zone is called the Alltarctic
converge11ce. This convergence is the northernnlost
boundary of the Antarctic seas, generally about 55 de-
grees south latitude.
Penguins climb on the ice shelf near the Antarctic peninsula, near
The continental shelf of Antarctica is very narrmv.
the U,S. scientific station at Palmer.
Oceanic basins 13,000 to 16,500 feet deep lie beyond the
steep continental slope. The northern edge of these basins
is the mid-ocean ridge system that separates the Antarctic
from the Atlantic, Indian, and Pacific Ocean basins. market fo]' whale products has dropped a lot, though, so
Millemls. Modern drilling and infrared photography the demand for whales has decreased. Iceland and Japan
have fotmd many minerals in Antarctica and its sur- still engage in some whaling, tmder some control by the
rounding seas, but these deposits are currently too ex- International Whaling Commission.
pensive to mine. There is SOll1e harvesting of krill, a name given to
Fishing. Whaling was a thriving business in the small shrimp-like animals that abound in some Antarctic
Antarctic for a htmdred years tmtil the early 19305. Then waters during certain seasons of the year. Tbis is of only
modern floating factory ships and fast whalers with har- limited cOllunercial value.
poon guns nearly wiped out the whale population. Oniy Ports alld Naval Bases. There is a research base at
about one-tenth of the original whale population still McMurdo Sotmd nm by the National Science Fotmda-
survives, and a lllunber of species are nearly extinct. The tion, which the u.s. Navy helps to maintain and supply,