Geography Reference
In-Depth Information
our terms of reference will need to be ever more flexible to acknowledge bi-polar, global,
and even extra-terrestrial connections, including the Moon (for parallels with Earth).
Making and unmaking the Antarctic
A satellite composite image of the Antarctic, a rather recent representation of the region,
reveals a continent composed of two parts - East and West Antarctica with the western
section characterized by a serpentine tail pointing towards the southern tip of the South
American continent. The Southern Ocean is far removed from other continents and accom-
panying centres of population. The continent itself encompasses some 14,000,000 square
kilometres, some 6,000,000 square kilometres larger than the United States. The coastline
encompasses nearly 18,000 kilometres and is composed of a mixture of ice shelves, ice
walls, rock and ice streams. The Antarctic ice sheet covers about 98% of Antarctica, and
is on average 1.6 kilometres thick and some 25 million cubic kilometres in volume. The
continent contains 90% of the world's ice and 70% of the world's fresh water. If the ice
sheet was to melt in its entirety, then sea water levels would, it is believed, rise by some 60
metres, with devastating consequences for lower-lying regions around the world.
But this satellite image, however striking, is misleading. The Antarctic is the world's most
unstable space, with extraordinary changes being recorded every year in terms of snow ac-
cumulation and sea ice extent. The satellite image literally freeze frames. Every September,
in the late winter period, the size of the continent effectively doubles. A large area of the
Southern Ocean extending more than 1,000 kilometres from the coastline is temporarily
covered in sea ice. This capacity to alter has, over time, played havoc with attempts to map
and chart the Antarctic. Countless explorers and mariners have discovered to their cost
that existing maps are hopelessly inaccurate, and that there is a rich tradition of islands
and coastlines being in the 'wrong place' or simply 'disappearing'.
Geologically, the Antarctic has a long and complex history, its composition ranging from
Precambrian crystalline rock to glacial deposits of a recent vintage. Some of the world's
oldest rock is found in the Antarctic, dating back some three billion years. Geological evid-
ence suggests that the Antarctic has not always been characterized by the snow and cold;
it was, for much of its history, a green continent. Sedimentary rocks, to be found in the
Antarctic Peninsula region, reveal fossilized tropical ferns and pollen specimens, while
coal deposits in the Trans-Antarctic Mountains suggests a climate favouring temperate ve-
getation. In the Cambrian era (590 to 505 million years ago), what we now term Antarctica
was part of Gondwanaland, a super-continent composed of present-day South America,
Africa, and Australia as well as parts of India, Madagascar, and New Zealand. It straddled
