Snow and ice
are pervasive elements of high latitude environmental systems and have an
active role in the global environment. Glaciologists in Antarctica are
concerned with the study of the history and dynamics of all naturally occurring
forms of snow and ice, including floating ice, seasonal snow, glaciers, and
continental and marine ice sheets.
One priority
for scientists is to determine the origins of the polar ice sheet, along with
the fundamental behavior of the ice sheet during worldwide glaciations. Data
has shown that the East Antarctic ice sheet has remained relatively static
during worldwide glaciation whereas the marine-based West Antarctic Ice sheet
has expanded to the eastern edges of the Ross and Weddell continental shelves,
nearly tripling in size in the process.
Of critical importance to
glaciological research is the examination of deep ice cores. Ice cores are
unique in that they continuously record and preserve annual precipitation,
atmospheric temperature and components of the atmosphere, including gases,
soluble and insoluble aerosol particles from a wide variety of sources.
Another focus
for scientists is to improve our understanding of the growth and movement of
Antarctic sea ice, not only to aid in navigation but to give insight into
future changes. Sea ice originates on or at the edge of the polar land mass and
is dispersed by strong winds blowing northward into the surrounding oceans. Annually
the ice pack grows from an average minimum of 2.9 million square kilometers in
March to about 18.8 square kilometers in September. The average thickness of
the sea ice is about 1.5 meters and 85 percent of the ice pack melts each year.
This ice is characterized by undulating ridges and troughs and crevassed areas
which have created route-finding problems for those traveling across these
marginal areas of the ice shelf. The
pack moves quickly with the winds--as much as 65 kilometers in a single
day--and ships can easily be caught in some of the thicker, more complex
multiyear ice that is trapped within indentations on
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