Exam Golden Line: “Weather is short-term, climate is long-term average.”

Water has a **high specific heat capacity** – it heats up and cools down very slowly.

• In summer → sea remains cooler than land → cool sea breeze keeps coastal areas cooler.
• In winter → sea remains warmer than land → warm sea breeze keeps coastal areas warmer.

Result: Coastal places (Mumbai, Chennai) have **milder (moderate)** temperature throughout the year.
Inland places (Delhi, Nagpur) have **extreme** temperature – very hot summers, very cold winters.

Exam Golden Line: “Sea moderates temperature of coastal areas due to high specific heat capacity of water.”

Monsoon winds are the **backbone of India’s climate**:

• Southwest Monsoon (June–Sep): Brings 75–90% of India’s annual rainfall → lifeline for agriculture.
• Northeast Monsoon (Oct–Dec): Brings rain to Tamil Nadu, Kerala coast.
• Decides whether there will be good harvest or drought.
• Failure or delay of monsoon → drought, famine.
• Excess rainfall → floods.

Exam Golden Line: “Monsoon winds bring most of the rainfall in India and determine the success of agriculture.”

Exam Golden Line: “Chennai is near the sea and at low altitude → warm climate. Leh is at high altitude → cold climate.”

(a) The climate of India is of tropical monsoon type.

(b) The southwest monsoon brings rainfall to most parts of India.

(c) Mawsynram in Meghalaya receives the highest rainfall in the world.

(d) The retreating monsoon winds cause rain along the Coromandel coast.

(e) Global warming is causing climate change.

(i) India has only one type of climate. → False

(ii) The southwest monsoon winds blow from June to September. → True

(iii) The Western Ghats receive less rainfall than the Eastern Ghats. → False

(iv) Climate change is caused only by natural factors. → False

(v) The Himalayas protect India from cold winds from Central Asia. → True

(a) The southwest monsoon is very important for India.
It brings 75–90% of India’s annual rainfall. Most of our agriculture depends on this rain. Without it, there would be drought and food shortage.

(b) There is heavy rainfall on the western coast but less rainfall on the eastern coast.
The southwest monsoon winds hit the Western Ghats first → heavy rain on windward side. By the time they cross the Deccan Plateau, they lose moisture → less rain on Eastern Ghats (rain shadow region).

(a) What is monsoon? Name the two branches of the Indian monsoon.
Monsoon is a seasonal wind that reverses its direction twice a year. The two branches are:
1. Arabian Sea branch
2. Bay of Bengal branch

(b) How is the retreating monsoon different from the advancing monsoon?
Advancing (southwest) monsoon: June–Sep, brings heavy rain.
Retreating (northeast) monsoon: Oct–Dec, mostly dry except Tamil Nadu coast.

(c) Name any four effects of climate change.
1. Melting of Himalayan glaciers
2. Rise in rainfall pattern (more floods/droughts)
3. Rise in sea level
4. More frequent heat waves and cyclones

(a) Describe the mechanism of the Indian monsoon.
In summer, land (India) heats faster than sea → low pressure over north India. Sea has high pressure. Moist winds from Indian Ocean rush towards low pressure. Western Ghats block Arabian Sea branch → heavy rain on west coast. Bay of Bengal branch spreads over northeast and Ganga plain → widespread rain. This is called southwest monsoon (June–September).

(b) How does climate affect our food, clothing and housing? Give examples.
• Food: Wheat in north (cool winters), rice in south & east (heavy rain), fish in coastal areas.
• Clothing: Woollens in Himalayas, cotton in plains, raincoats in Cherrapunji.
• Housing: Sloping roofs in heavy rainfall areas (Assam, Kerala), flat roofs in dry areas (Rajasthan), bamboo houses in northeast.

(i) Areas of heavy rainfall (>200 cm)
(ii) Areas of moderate rainfall (100–200 cm)
(iii) Areas of low rainfall (<50 cm)
(iv) Direction of southwest monsoon winds

Collect newspaper clippings about recent floods, droughts or cyclones in India. Discuss in class how climate change is making these events more severe.