Glasgow Digital Library Voyage of the Scotia BRUCE PEOPLE SHIP ANTARCTIC INDEX
Scotland and the Antarctic

Section 1: Background - Arctic and Antarctic ... Comparison of Arctic and Antarctic regions

The Antarctic

Small outline map of the Antarctic

The Antarctic continent is about the size of the USA and Mexico combined. The continent is covered by the largest mass of ice in the world which is up to 4,700 metres thick (15,400 feet) over East Antarctica. The average thickness of the ice is 2,500 metres (8,200 feet). Ice covers 99% of the continent. The ice is moving outward from the centres of East and West Antarctica towards the southern ocean where it breaks off into great tabular icebergs. These can be the size of a small country such as Belgium. Some of the largest glaciers in the world carry the ice towards the sea in Antarctica.

In winter, the sea ice extends over 20 million km2, doubling the size of the continent. In summer the sea ice still covers a large area. Five million km2 or 89% of the land ice is over East Antarctic (which forms 66% of the land area of Antarctica).

Physical features

Antarctica is the highest continent in the world with an average height of 2,300 metres (7,500 feet). The highest point, Mount Vinson, is 4,897 metres (16,066 feet) high. East Antarctica consists of a Pre-Cambrian shield similar to the land of the Arctic. This is separated from the younger rocks of West Antarctica by the Antarctic Mountains. There were many active volcanoes in Antarctica's geological past but today there are only two active volcanoes - Mount Erebus and Deception Island.

Climate

The Antarctic is the coldest place in the world. Temperatures in Antarctica are generally 10-30C lower than the same latitudes in the Arctic. The world record low temperature was recorded at Russia's Vostok base in 1983, at -89.2C. The mean annual temperature at Vostok is -55C.

Temperatures are low all year round in the Antarctic, averaging -70C in winter at the ice centre and -25C on the coast. In summer (January) temperatures average -40C in the ice centre and -2C on the coast.

Precipitation in the centre of East Antarctica is only 50mm (similar to the world's great hot deserts), 70mm at the South Pole and 200-600mm around the coast.

Flora

The cold temperatures all year round severely restrict plant growth in the Antarctic. On the continental land mass 99% of the land is covered with ice so only on the periphery are any primitive plants found - mainly mosses with a few grasses. More plant life is found on the Antarctic islands. In the last 30 years plant life in the Antarctic has doubled in area owing to global warming.

Fauna

There are no land mammals in the Antarctic as the temperatures are so severe in winter and still very cold in the summer months. Marine mammals and birds are the main inhabitants. Many of the birds migrate to warmer climates in the winter months.

The seas around the Antarctic are very rich in plankton in the summer months and teeming with krill (a small shrimp-like creature). These provide the main food for penguins (there are millions of these in the Antarctic), other sea birds, seals and whales.

Human impact

The earliest people in the Antarctic were the explorers looking for new lands. The greatest number of people who came south in the nineteenth century were looking for seals and whales. The economic aspects of the Antarctic were the greater attraction at first. Next came the scientists trying to find out about life in the south, about the climate and trying to improve their knowledge of the world's magnetic field (which was so important for navigation at that time).

The next phase saw the attempts to reach the South Pole. The North Pole had been reached in 1908-09. There were several expeditions to the South Pole before the Norwegian Roald Amundsen reached it in 1911.

Seven countries claimed large areas of land in the Antarctic - the claims of Britain, Chile and Argentina overlapped. In 1958, under the Antarctic Treaty, all territorial claims were set aside and the 23 signatories of the Treaty agreed that this last great wilderness would only be used for scientific research. There was to be no military presence south of 60S. This system has worked well for over 40 years and has resulted in valuable research which includes work on global warming and the discovery of the hole in the ozone layer.

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Glasgow Digital Library Voyage of the Scotia BRUCE PEOPLE SHIP ANTARCTIC INDEX