选修八Module1DeepSouth.doc

选修八Module1DeepSouthModule 1 Deep SouthAntarctica： the Last ContinentAntarctica is the coldest place on Earth. It’s also the driest With annual rainfall close to zero， Antarctica is technically a desert Covering about 14 million square kilometers around the South Pole， it is the fifth largest continent in the world. A high mountain range， the Trans—Antarctic range, runs from east to west， cutting the continent in two. There are volcanoes too, but they are not very active. Antarctica holds 90% of the world’s ice， and most of its fresh water (70%） is in a frozen state， of course。

98% of the surface is covered permanently in the ice cap. On average it is two kilometers thick, but in some places it reaches a depth of five kilometers Strong winds driven by gravity blow from the pole to the coastline, while other winds blow round the coast. It is difficult to imagine a more inhospitable place Yet Antarctica is full wildlife， which has adapted to its extreme conditions. There are different types of penguins， flying birds， seals, and whales. But the long Antarctic winter night， which lasts for 182 days （the longest period of continuous darkness on earth)， as well as the extreme cold and lack of rainfall， means that few types of plants can survive there。

Only two types of flowering plants are found， while there are no trees on the large continent. The rest of the plants are made up of mosses， algae and lichen. Some forms of algae have adapted to grow on ice Most of the ice has been there for thousands of years As a result， it has become a window on the past， and can give researchers lots of useful information Gases and minerals， in the form of volcanic dust trapped in the ice， can tell us a lot about what the world's climate was like in past ages. Antarctic rocks are also very important for research。

Most of them are meteorites from outer space One rock, known as the “Alien” rock, may contain evidence of extra—terrestrial life Since most Antarctic rocks are dark in colour, they stand out against the white background and are easy to identify and collect. Antarctica was the last continent to be discovered But more than two thousand years ago Greek geographers believed that there was a large land mass in the south which balanced the land in the north They called it Anti—Arktikos， or Antarcica： the opposite of Arcitc。

When Europeans discovered the continent of America in 15th century， the great age of exploration began However， progress to the South ole was slow. Not until the late 18th century did the British explorer James Cook cross the Antarctic Circle， but he never saw land. Then in 1895, a Norwegian called Carstens Borchgrevink became the first man to set foot on the Antarctic mainland The race to the pole had begun It was finally reached on 11th December, 1911 by the Norwegian Roald Amundsen. Today scientists from many countries travel to Antarctica to study its resources。

A spirit of international friendship has replaced the rivalry that existed between many of the earlier explorers. In 1961， a treaty signed by 12 countries, including Britain， France, and the USA made Antarctica the world’s biggest nature reserve The aim of the treaty is to prevent the commercial and military use of the continent. In particular， it aims to keep Antarctica free from nuclear tests and radioactive waste； to promote international scientific projects； and to end arguments about who owns the land. Today countries representing 80% of the world's population have signed the treaty。

Antarctica has become perhaps the most successful symbol of man's efforts to work together for progress and peaceHow Failure Became SuccessOn 8th August, 1914, 27 men who had replied to an advertisement in The Times boarded a ship leaving for the Antarctic The name of the ship was the Endurance and the captain was an Irishman called Ernest Shackleton. The aim of the journey was to cross the frozen continent via the South Pole – journey of 1，800 miles. Shackleton thought the journey would last six months. But when land came into sight, the Endurance became trapped in the ice and began to break up。

Shackleton and his men watched the Endurance sink into the icy sea. They then headed north, pulling three lifeboats behind them. After six days, bad weather forced them to give up and the men set up camp on a sheet of ice which began slowly moving across the Antarctic Circle. They survived on the ice for five months Then, on 16th April, 1915, Shackleton saw land. It was Elephant Island – large rock with nothing growing on it， but much better than a floating piece of ice. When they reached the island, Shackleton came up with an idea – it was a risk but he would have to take it. He and five men would take one of the lifeboats, and sail 800 miles to South Georgia， where there was a permanent camp. They could then return to rescue the rest of the men. It took Shackleton 17 days t。