Class 8 Social Science Part 2 Chapter 1: World Geography: Some Glimpses Notes

What is this chapter about?

In India the Earth has long been honoured as a mother, Bhudevi or Vasudha, and our lives depend on features far away: winds over the distant southern Indian Ocean help bring the monsoon to the Gangetic Plains. This chapter takes a quick tour of the planet. It asks three Big Questions: what makes each continent’s physical features special, why we should understand world geography, and how human actions cause environmental problems.

Mapping a round Earth

The Earth is an oblate spheroid, almost a ball but slightly flattened at the poles. Try to press the peel of an orange flat and it splits, and in the same way no flat map can show the Earth without distortion. Each map projection makes a different compromise. The Mercator projection keeps shapes and directions, so it suits navigation, but it swells lands near the poles until Greenland looks as large as Africa. The Robinson projection balances size and shape and looks more natural. For exact positions, professionals use latitude and longitude. Read mapping the Earth.

The blue planet

Oceans cover about 71% of the Earth’s surface and hold about 97% of its water. They are home to everything from plankton, which give us almost half our oxygen, to the blue whale, and they control climate by storing heat and adding moisture to the air. Currents move water like rivers in the sea: the warm Gulf Stream keeps the United Kingdom milder than other places at its latitude. The seafloor has mountains, plains and deep trenches; the Challenger Deep in the Mariana Trench is over 11,000 m deep. Coral reefs such as the Great Barrier Reef shelter a quarter of all ocean species. Smaller seas, gulfs, bays, straits and canals carry trade, and the Suez Canal, opened in 1869, is the shortest sea route from India to Europe. Read continents and oceans.

Asia and Europe

The tour starts near home. North of the Himalayas lies the Tibetan Plateau, the highest and largest plateau, pushed up by the same collision of tectonic plates that raised the Himalayas. Called the Third Pole, it stores more fresh water than anywhere outside the polar regions and feeds the Indus, Brahmaputra and Yangtze. To the north-east is the cold Gobi Desert, then the vast Eurasian Steppes, a grassland that locks carbon into the soil. The old Ural Mountains separate Europe from Asia. West of them spreads the fertile European Plain, and to its south the crescent of the Alps, which feeds the Rhine and the Danube.

Africa and the Americas

The Sahara is the largest hot desert, crossed for centuries by nomads and traders in gold and salt. South of it the savannah, a grassland with scattered trees, supports elephants, lions, zebras and giraffes, and the Nile, about 6,650 km long, gave rise to ancient Egypt. In South America the Andes feed the Amazon, the largest river by volume, whose rainforest is called the ‘Lungs of the Earth’, while the Atacama is one of the driest places on Earth. North America has the Colorado Plateau with the Grand Canyon, the Rocky Mountains with Yellowstone, the very old Appalachians and the five Great Lakes.

Australia and Antarctica

Much of Australia is dry land, the Great Australian Desert, which includes the Great Victoria Desert. Wallabies, bilbies, dingoes and wild camels live there, and the Spinifex people have lived in it for over 25,000 years. The largest desert of all is not hot: Antarctica, over 14 million km², over four times as big as India, is the coldest desert on Earth.

People and the planet

Everywhere on the tour, human actions leave marks. Changing ocean water bleaches corals, forests are cleared in the Amazon, melting permafrost releases greenhouse gases, and cheap clothes pile up in the Atacama. Care can also heal: wolves brought back to Yellowstone in 1995 restored the balance of its ecosystem. Read human actions and environmental issues.

Looking back and forward

The chapter ends with a bridge to the next one, recalling two early revolts in Odisha. In the Paika Sangram of 1817, the Paikas, peasant soldiers who had lost their lands to high British revenue demands, rose with tribal groups under Buxi Jagabandhu and took Puri. In Sambalpur, Surendra Sai led resistance from 1827 to 1862.

Before we move on

The Earth’s mountains and plateaus, its plains, deserts and grasslands, and its rivers and oceans shape climate, wildlife, farming, settlement and trade. Human actions such as cutting forests, overusing resources and polluting upset this balance, so understanding world geography helps us use the planet wisely. Answers to every question are in the NCERT solutions for Part 2 Chapter 1.