Climatic Regions of the World Notes for UPSC

The world is not the same everywhere: some places are hot and wet all year, some are dry deserts and some are frozen. Geographers group places with a similar pattern of temperature, rainfall, vegetation and human life into climatic regions. The most widely used system is the Koppen classification, which divides the world into five main groups (A, B, C, D and E) and a highland type, using temperature and rainfall. For UPSC, this chapter is important for Prelims (region, location, vegetation, crops) and Mains (agriculture, population distribution and climate change). In this note, we study the major regions in a simple way.

Koppen's Five Climate Groups

A separate Highland (H) climate is found on high mountains, where the climate changes with altitude. Let us study the main regions in order from the equator to the poles.

1. Equatorial (Tropical Rainforest) Climate

Location: within about 5 to 10 degrees on both sides of the equator, such as the Amazon basin, the Congo basin and Indonesia. Climate: hot and wet all year, with a temperature of around 27 degrees Celsius and very little change between seasons. Heavy convectional rain falls almost every afternoon, giving more than 200 cm a year. Vegetation: dense, tall, evergreen forests with many layers and a very rich biodiversity (called selvas in the Amazon). People: a small population living by hunting and shifting cultivation, such as the Pygmies of the Congo.

2. Tropical Monsoon Climate

Found in India, Bangladesh, Myanmar, Thailand, the Philippines and northern Australia, this climate has a clear wet summer (monsoon rain) and a dry winter. The natural vegetation is mostly deciduous forest (teak and sal), and the dense population grows rice, jute, sugarcane and tea.

3. Savanna (Tropical Wet and Dry) Climate

Found between about 5 and 20 degrees on both sides of the equator, in Africa (east and south), Brazil and Australia, this region has a rainy summer and a long dry winter, with 75 to 150 cm of rainfall. The vegetation is tall grass with scattered trees (acacia and baobab). It is the home of wildlife such as lions, elephants, zebras and giraffes, as in the Serengeti, and the Masai people of East Africa rear cattle here. In South America, the savanna is called the Llanos (Orinoco basin) and the Campos (Brazil).

4. Hot Desert Climate

Found around 15 to 30 degrees latitude on the western sides of continents, hot deserts include the Sahara (the largest hot desert), the Arabian, Thar, Kalahari, Australian and Atacama (the driest place on Earth). The sky is clear, rainfall is below 25 cm, the days are extremely hot (over 45 degrees Celsius) and the nights are cold, so the daily range of temperature is very large. Cold ocean currents and the sinking dry air of the sub-tropical highs cause this dryness. Vegetation includes cacti, thorny bushes and date palms near oases. People such as the Bedouins and Tuaregs are nomads who rear camels and goats.

5. Mediterranean Climate

This climate lies on the western margins of continents between about 30 and 45 degrees latitude: the Mediterranean region, California, central Chile, south-west Africa (Cape Town) and south-west and south Australia. It has hot, dry summers and mild, rainy winters, so it is unique because rain comes in winter. The vegetation is evergreen shrubs and short trees with thick, waxy leaves to avoid water loss. The region is famous for citrus fruits (oranges, lemons), olives, grapes and wine, and is called the "Orchard of the World".

6. China Type (Humid Subtropical) Climate

This is found on the eastern sides of continents between 25 and 35 degrees, such as south-east USA, central and southern China and parts of Argentina and Australia. Summers are warm and humid with heavy rain from monsoon winds or tropical storms, and winters are mild. Farmers grow rice, tea, cotton, maize and soybean, and many areas are densely populated.

7. Marine West Coast (British Type) Climate

Located on the western margins of continents between 40 and 60 degrees, such as the United Kingdom, north-western Europe, British Columbia (Canada), southern Chile and New Zealand. The westerlies and warm ocean currents bring mild winters, cool summers and rain throughout the year. Deciduous forests, dairy farming and fishing are important, and there are many industrial regions with high population.

8. Temperate Continental (Steppe) Climate

In the interior of continents, away from the sea, the summers are warm and the winters cold, and rainfall is moderate and low. The natural vegetation is temperate grassland, and these areas have different names in different countries: Prairies (North America), Pampas (Argentina), Veldt (South Africa), Downs (Australia) and Steppes (Eurasia). They have become the great wheat belts, called the "granaries of the world", with large mechanised farms and cattle ranching.

9. Taiga (Siberian) Climate

Located between about 50 and 70 degrees north in Siberia, Canada, Alaska and Scandinavia, it has very long, harsh winters (temperatures can fall below minus 50 degrees Celsius) and short, mild summers. The vegetation is coniferous forest (pine, spruce and fir), which provides softwood for timber, paper and furniture. Population is thin, with fur trading and lumbering as occupations.

10. Tundra and Polar Climates

The tundra lies north of the Arctic Circle and has permafrost (permanently frozen ground), with only mosses, lichens and small shrubs for vegetation, and reindeer, polar bears and musk ox as animals. People like the Inuit live there. Polar ice cap regions, Antarctica and Greenland, are always covered with ice, have no vegetation and have no permanent population except research stations. India has research stations in Antarctica (Maitri and Bharati) and in the Arctic (Himadri).

11. Highland Climate

In high mountains such as the Himalayas, Andes and Alps, temperature falls with height (about 6.5 degrees Celsius per km), and the vegetation changes in zones from forests at the bottom to alpine meadows, bare rocks and snow at the top. This is called altitudinal zonation.

Quick Comparison of Key Regions

Why Do Climatic Regions Matter? (Mains Angle)

Climate decides what people can grow and where they can live. Wheat belts lie in the temperate grasslands, plantation crops like rubber and cocoa in the tropical rainforests and fruit and wine in the Mediterranean region. Population is dense in the monsoon and humid subtropical regions and thin in deserts, the taiga and polar areas. Climate change is shifting these zones: deserts are expanding, the Arctic is warming fast and tropical diseases are moving to new areas. A good answer connects climate with agriculture, settlement, biodiversity and the need for adaptation.

How to Study Climatic Regions

1. Make a world sketch map and shade each region in a different colour, marking examples on the west and east margins of continents.
2. Remember the logic: west margins have Mediterranean and marine climates, east margins have China-type and Laurentian climates, interiors have steppes and the equator has rainforest.
3. Link each region with its crop, animal and people in a one-page table.
4. Practise PYQs that ask you to identify a region from a description of its rainfall and vegetation.

Practice Statements and Common Mistakes

• "The Mediterranean climate has hot, dry summers and mild, wet winters." Correct.
• "The Atacama is the largest hot desert." Wrong. The Sahara is the largest hot desert; the Atacama is the driest.
• "Prairies are the temperate grasslands of Argentina." Wrong. The Pampas are in Argentina; Prairies are in North America.
• Do not mix up the taiga (coniferous forest) and the tundra (no trees, permafrost).

Quick Revision

• Koppen groups: A tropical, B dry, C warm temperate, D cold continental, E polar.
• Grasslands: Prairies, Pampas, Veldt, Downs and Steppes; Savanna: Llanos and Campos.
• Mediterranean: winter rain; hot desert: Sahara and Atacama; taiga: coniferous forest.

Climatic regions help us understand the whole world in a systematic way. Memorise the table of regions with their locations, examples and vegetation, use a world map to mark them and practise a Mains answer on how climate shapes human life, and this chapter will help you score well.

Related Notes to Read Next

Continue your preparation with these related notes from the same subject:

• Major Mountains, Rivers, Lakes and Deserts of the World Notes
• Geomorphology Notes for UPSC
• Minerals, Energy Resources and Industries of the World Notes
• All World Geography notes

Frequently Asked Questions (FAQ)

What is the Koppen climate classification?

The Koppen classification divides the world’s climates into five groups (A tropical, B dry, C warm temperate, D cold continental and E polar) plus highland, based on temperature and rainfall.

Where is the equatorial climate found?

The equatorial climate is found within 5 to 10 degrees on both sides of the equator, in regions like the Amazon basin, the Congo basin and Indonesia, with hot, wet weather all year.

What is savanna climate?

Savanna climate has a rainy summer and a dry winter, and the vegetation is tall grass with scattered trees. It is found in Africa, Brazil and Australia and is famous for wildlife.

Why are hot deserts found on the western sides of continents?

They lie under sub-tropical high-pressure belts where dry air sinks, and cold ocean currents along western coasts reduce rainfall, which creates deserts like the Sahara and the Atacama.

What is special about the Mediterranean climate?

The Mediterranean climate has hot, dry summers and mild, rainy winters, which is unusual because rain falls in winter. It supports citrus fruits, olives and grapes.

What are the temperate grasslands of the world called?

They are called the Prairies in North America, Pampas in Argentina, Veldt in South Africa, Downs in Australia and Steppes in Eurasia.

What is taiga?

Taiga is the vast belt of coniferous forest in the cold northern regions of Siberia, Canada and Scandinavia, which has long, harsh winters and short summers.

What is tundra?

Tundra is a cold region north of the Arctic Circle with permanently frozen ground (permafrost) where only mosses, lichens and small shrubs grow.

Which is the largest hot desert in the world?

The Sahara in North Africa is the largest hot desert in the world, while the Atacama in Chile is the driest.

What is marine west coast climate?

It is the mild, rainy climate of the western margins of continents between 40 and 60 degrees latitude, such as the United Kingdom, which gets rain all year and has mild winters.

What is altitudinal zonation?

Altitudinal zonation is the change of climate and vegetation with height on a mountain, from forests at the base to alpine meadows, bare rocks and snow at the top.

Why are the temperate grasslands called the granaries of the world?

The temperate grasslands have fertile soil and a climate suitable for wheat, so large-scale mechanised wheat farming makes them major producers of grain for the world.