SOIL ----GEOGRAPHY FORM THREE BY AIKANDE URASA & YAHYA R. MAFIGA ----- TANZANIAN SYLLBUS

PHOTOGRAPH READING AND INTERPRETATION ---- GEOGRAPHY FORM THREE BY. AIKANDE URASA & YAHYA R. MAFIGA

MAP READING AND MAP INTERPRETATION ---- GEOGRAPHY FORM THREE BY AIKANDE URASA & YAHYA R. MAFIGA

ELEMENTARY SURVEYING AND MAP MAKING-----GEOGRAPHY FORM THREE BY AIKANDE URASA & YAHYA R. MAFIGA

POLAR AND TUNDRA REGIONS -----ENVIRONMENTAL ISSUES

POLAR    AND    TUNDRA       Environmental Issues

The Arctic region has many minerals that are important to people like: iron, gold and oil. People live and work in the Arctic to remove these valuable minerals and sell them but this has its advantages and disadvantages:

Advantages	Disadvantages
The oil and gas bring money to the region. Jobs are provided for local people and migrant workers from different countries. It provides power for the local people.	Forests which have taken a long time to grow are destroyed by the building of roads and pipelines. More pollution is released into the atmosphere, increasing the acidity of rain. Acid rain can damage soils and kill trees. There is a danger of a big oil spill or gas explosion

POLAR AND TUNDRA REGIONS----- PEOPLE

PEOPLE

Only a few thousands people live in the tundra regions. The Inuit live in northern Canada, Greenland and Alaska. The Lapps (or Sami) herd reindeer in northern Scandinavia in an area nicknamed Lapland.

Traditionally, the Inuit were hunters and fishermen: in winter they fished for seals below the ice and in summer they hunted for caribou on the land. They travelled by sledge and built temporary ice shelters called igloos.

To help them survive in the cold, stormy weather, they had to wear thick, warm clothes like coats and salopettes (trousers) which are waterproof and have fur inside to insulate them.
Their boots had special tennis racket-like soles so their body weight was spread out and they didn't sink in the soft snow.
Despite it being freezing, the sun is always shining so the Inuits had to wear tinted goggles and a mask to stop them going snow blind.

Today, many Inuit dress in modern clothes. Some have motor-powered snowmobiles and live in homes made of modern materials. Some homes have: electricity, double-glazed windows and telephones. Heated houses have to be built on stilts so that the permafrost does not thaw. If it did, the ground would give way. Water pipes are insulated and run above ground to stop them freezing.

Modern foods and other goods are flown into the towns to be sold in supermarkets so living costs are now high. Imported food has created health problems for the Inuit as it is rich in carbohydrates and sugar not found in their traditional diet

POLAR AND TUNDRA REGIONS---- PLANTS

PLANTS

The plants growing in the tundra are often small and grow close to the ground: Lichen is a plant that is a mixture of both fungus and an alga. It grows well without soil, even on bare rock. It is an important food for creatures like reindeer, which dig underneath the snow-covered soil to find it.  Mosses are flowerless plants that grow very close to the surface of the ground, forming a soft, spongy cushion. They have tiny rootlets that absorb moisture and minerals. Many plants have dark red leaves so they can absorb as much heat from the sun in the cold tundra climate as possible.

POLAR AND TUNDRA REGIONS ----- GEOGRAPHY

ANIMALS

In the Arctic, many animals live on land, while in Antarctica, life is mainly based in the surrounding waters.  Animals in both polar regions have had to adapt to survive in the extreme cold: Polar bears: are white to help them camouflage (hide) easily in the snow from hungry predators, have large paws to help them grip the ice and have thick fur to help them keep warm. Reindeer (also called caribou) feed on grasses and plants in the tundra in the summer and then travel (migrate) south in winter to warmer places. The underside of each hoof is hollowed out like a big scoop and allows them to dig through snow in search of food. They also use their hooves to paddle through chilly northern rivers and lakes. Musk oxen have a fine layer of wool under a thick outer coat. They crowd together so water vapour in their breath forms a cloud to trap heat. Arctic foxes have white fur in the winter to help them blend in with the snow - they then shed this for a brown one as the snow melts in the summer. They have a long, bushy tail which they use to keep their nose and feet warm when asleep too. Walruses have sharp tusks to help protect them from polar bears and use special air sacs in their neck to help them keep their head above water when swimming. Penguins (that only live in Antarctica): have dark feathers on their backs to absorb heat from the sun and have lots of blubber (fat) under their skin to help insulate their bodies. They also huddle together with other penguins to keep warm. Weddell seals live further south than any other mammal. They have grooves in their teeth to help them break holes in the Antarctic ice and can swim underwater for over an hour to look for food.

POLAR AND TUNDRA REGIONS --- CLIMATE

CLIMATE

The polar regions are very cold because the Sun's rays are weakest at the North and South Pole. Powerful, icy-cold winds blow throughout the year. Often the wind sweeps up powdery snow from the ground and swirls it around, causing cold blizzards. Very little new snow or rain falls as it is too cold for moisture to evaporate. The wind chill can make the temperature appear even lower than it actually is. An actual temperature of -6oC, for example, would make it feel a bitterly cold -34oC when the effect of wind chill is added on. Temperatures as low as -50oC have even been recorded. The ground in the Tundra regions around the edge of the Arctic stays frozen for nine months of the year. In the summer months, only the surface thaws and deeper ground stays frozen. This frozen layer is called permafrost. Melted snow cannot seep through the permafrost so, in the summer, the surface of the tundra lands becomes boggy. The landscape of the tundra is therefore a treeless plain covered with moss and some grass-like plants.

POLAR AND TUNDRA REGIONS --- AREAS AND POSITION

Polar and Tundra Regions

The polar regions are the coldest places on Earth: Antarctica is at the South Pole and is a continent of ice-covered rock; the Arctic is at the North Pole and consists of a frozen ocean, surrounded by a vast expanse of tundra - tree-less plains. The Arctic and Antarctic circles are lines of latitude going around the Earth that mark the outer limit of the two polar regions. They are found at 66oN and 66oS of the Equator. Inside these circles, the tilt of the Earth causes long summer - and short winter - days to occur. At the poles themselves, six months of unending sunlight alternate with a six-month period of darkness. Many places within the Arctic circle are nicknamed 'the Land of Midnight Sun' because the sun hardly ever disappears and it can be daylight for nearly 24 hours in the summer. The night skies in the polar regions can be filled with gently rolling coloured lights. In the Arctic they are called the Aurora Borealis and in Antarctica they are called the Australis. They are formed as solar winds hit the Earth's magnetic field and release light particles.