The geographic North and South poles are the poles the earth spins around, the ones people see on a globe where all the north/south lines meet. These poles stay in the same place, and are usually the ones we mean if we just say North or South Pole. People can tell that they are at these poles by looking at the stars (at the poles, a star just circles around at the same height, never dipping to the horizon). The Sun rises once a year and gives the South Pole half a year of summer but it is always cold. When the Sun sets half a year later it makes half a year of winter which is even colder. The South Pole is always cold because the Sun never rises high in the sky.
The south magnetic pole is something different. It is defined by the Earth's magnetic field, as roughly where a magnetic compass needle points. People can tell they are near these poles by looking at a compass.
The South Pole is hard to reach. Unlike the North pole, which is covered by the sea and flat sea-ice, the South Pole is on a mountainous continent. This continent is called Antarctica. It is covered by thick ice (more than a mile thick in the centre). The south Pole is very high up, and is very windy. It is far from places where people live, and ships going there often have to find their way through thick sea ice. Once ashore, land-travelling explorers have to travel more than a thousand miles to get to the pole. They must cross a floating ice shelf, then up onto the ice-covered land, up steep mountain glaciers covered in broken, twisted ice slowly sliding to the sea, and across a high level land ("plateau") covered in ice and swept by strong freezing winds.
Two expeditions early in the 20th century, led by Robert Falcon Scott and then Ernest Shackleton, failed to reach the South Pole, but returned safely. Shackleton turned back quite close to the pole, but it was late in the season and supplies were low. He knew that he would be risking the lives of his men, so he turned back.
The first men to reach the South Pole were a group from Norway led by Roald Amundsen. They arrived at the Pole on December 14, 1911 and left the Norwegian flag. Amundsen and his men returned home safely. Amundsen's story is one of excellent planning, good leadership, and willingness to learn from others: this made extreme endurance unnecessary, and perhaps made the successful expedition less of a story, and therefore perhaps less famous, than the next one.
The most famous South Pole expedition is perhaps the one that failed badly. This was the British expedition (not just UK, it included people from the British Empire, who at that time were considered British citizens) led by Robert Falcon Scott. Scott and four other men, dragging their equipment on sledges, had hoped to be first to the Pole. When they arrived, they saw a Norwegian flag. A letter left for Scott showed that Amundsen and his men had beaten them by a month, by using dogs to pull their sledges.
On their journey back from the Pole, Scott's team found that food "dumps" were short of supplies, particularly kerosene. Kerosene was very important: not just for cooking but for melting ice. Once it ran out, they would have no water to drink. One man collapsed and died while walking. Oates knew his frostbitten feet could not carry him back to base, and that he might delay his companions and risk their lives. He committed suicide by walking out of their tent into the cold. Scott and his remaining two companions died of starvation, thirst, and cold - trapped in the tent by bad weather until their supplies ran out. Next spring, the three bodies in the tent were found by a team from the main part of the expedition - who had spent the winter in the expeditions's hut by the sea. Scott's letters to his wife, written in the tent when he knew he was going to die, have just (Jan 2007) been made public.
Apart from Ernest Shackleton's expedition to cross the Antarctic (another heroic failure, but Shackleton saved all his men, after a very courageous sea crossing in an open boat, and a crossing of an unknown mountain range while starving and freezing), this was the end of the "heroic" age of exploration. Motors, Planes, Radios, and GPS ensured that following expeditions were never truly "unsupported".
Today there is an American science base at the South Pole. It is named the Amundsen-Scott South Pole Station to honor the two explorers.
The South Pole has a desert climate. It almost never gets any precipitation. Air humidity is near zero. However, high winds can cause the blowing of snowfall, and the accumulation of snow amounts to about per year. The former dome seen in pictures of the Amundsen-Scott station is partially buried due to snow storms, and the entrance to the dome had to be regularly bulldozed to uncover it. More recent buildings are raised on stilts so that the snow does not build up against the sides.
Indian Ocean
The Indian Ocean is the ocean surrounded by Asia to the north, Australia and the Pacific Ocean to the east, the Southern Ocean to the south, and Africa and the Atlantic Ocean to the west. It is named for the river Indus and Ancient India on its north shore. The Bay of Bengal, the Arabian Sea, the Persian Gulf and the Red Sea are all parts of this ocean.
The deepest point in the Indian Ocean is in the Java Trench near the Sunda Islands in the east, 7500 m (25,344 feet) deep. The average depth is 3,890 m (12,762 ft). The Indian Ocean is the third largest ocean, 28,350,000 square miles in size. The majority is in the southern hemisphere.
Arctic Ocean
The Arctic Ocean is the ocean around the North Pole. The most northern parts of Eurasia and North America are around the Arctic Ocean. Thick pack ice and snow cover almost all of this ocean in winter, and most of it in summer. An icebreaker or a nuclear-powered submarine can use the Northwest Passage through the Arctic Ocean to go between the Pacific and Atlantic oceans.
The ocean's area is about 14.056 million km, which is the smallest of the world's 5 oceans, and it has of coastline. The central surface covered by ice about thick. The biology there is quite special. Endangered species there include walruses, whales and polar bears. Year by year the Arctic Ocean is becoming less icy, as a result of global warming.
The average depth of the Arctic Ocean is . The deepest point is in the Eurasian Basin, at .
The Arctic Ocean covers an area of about 14,056,000 km. The coastline is 45,390 km (28,200 mi) long It is surrounded by Eurasia, North America, Greenland, and by several islands.
It is generally taken to include Baffin Bay, Barents Sea, Beaufort Sea, Chukchi Sea, East Siberian Sea, Greenland Sea, Hudson Bay, Hudson Strait, Kara Sea, Laptev Sea, White Sea and other bodies of water. It is connected to the Pacific Ocean by the Bering Strait and to the Atlantic Ocean through the Greenland Sea and Labrador Sea.
Countries bordering the Arctic Ocean are: Russia, Norway, Iceland, Greenland, Canada and the United States.
The Arctic Ocean is in a polar climate. Winters are characterized by the polar night, cold and stable weather conditions, and clear skies.
The temperature of the surface of the Arctic Ocean is fairly constant, near the freezing point of seawater. Arctic Ocean consists of saltwater but its salinity is less than other oceans. The temperature must reach −1.8 °C (28.8 °F) before freezing occurs.
Ice covers most of the Arctic Ocean. It covers almost the whole ocean in late winter and the majority of the ocean in late summer. Much of the Arctic ice pack is covered in snow for about 10 months of the year. The maximum snow cover is in March or April — about 20 to 50 cm (7.9 to 19.7 in).
The climate of the Arctic region has varied significantly in the past. As recently as 55 million years ago, during the eocene epoch, the region reached an average annual temperature of 10–20 °C (50–68 °F). The surface waters of the Arctic Ocean warmed enough to support tropical lifeforms.