NCERT Solutions for Class 9 Geography Chapter 4 Climate
NCERT Solutions for Class 9 Geography Chapter 4 covers Factors Affecting India's Climate, The Indian Monsoon, The Seasons in India, and Monsoon as a Unifying Bond.
Overview of Topics & Subtopics (Click to Jump)
1. Climate vs Weather & Factors Controlling Climate
Short Note:
• Weather vs Climate: Weather refers to atmospheric conditions at a specific point of time over a short period; Climate refers to the sum total of weather conditions over a large area for a long period (more than 30 years).
• 6 Major Controls of Climate: Latitude, Altitude, Pressure & Wind System, Distance from the sea (Continentality), Ocean currents, and Relief features.
2. Factors Affecting India's Climate & Indian Monsoon
Short Note:
• Factors Influencing India: Latitude (Tropic of Cancer), Altitude (Himalayas block cold Central Asian winds), Pressure and Winds (Jet Streams and Tropical Cyclones).
• Mechanism of Monsoon: Differential heating and cooling of land and water creates low pressure over the Indian landmass during summer. Shift of ITCZ (Inter Tropical Convergence Zone) over Ganga plain triggers south-west monsoon winds.
• Burst of Monsoon: Sudden onset of heavy rainfall around early June accompanied by thunder and lightning.
• El Niño: A warm ocean current off the coast of Peru that temporarily replaces the cold Peruvian current, causing weaker monsoon conditions in India.
3. The Seasons & Monsoon as a Unifying Bond
Short Note:
• 4 Main Seasons in India:
- Cold Weather Season (Winter): Mid-November to February; fine weather, light winds; Western Cyclonic Disturbances bring rainfall in northwest.
- Hot Weather Season (Summer): March to May; high temperatures; local wind storms like Loo, Kaal Baisakhi, and Mango Showers.
- Advancing Monsoon (Rainy Season): June to September; south-west monsoon covers whole country. Mawsynram receives highest rainfall in the world.
- Retreating/Transition Season (Autumn): October to November; clear skies, rise in temperature with high humidity (October Heat); tropical cyclones hit eastern coast.
• Unifying Bond: The seasonal rhythm of monsoons ties the whole Indian subcontinent together by shaping agricultural cycles, festivals, and water supply across all regions.
Intext & Conceptual Questions
'Loo' refers to strong, gusty, hot, and dry winds blowing during the daytime over northern and northwestern India during the summer season (May–June). Direct exposure to these winds can be fatal.
| Weather | Climate |
|---|---|
| State of atmosphere over an area at any specific point in time. | Sum total of weather conditions and variations over a large area over a long period (30+ years). |
| Changes frequently (day-to-day or hour-to-hour). | Remains stable and consistent over decades. |
Textbook Chapter End Exercise Questions
(a) Silchar (b) Mawsynram (c) Cherrapunji (d) Guwahati
Answer: (b) Mawsynram
(ii) The wind blowing in the northern plains in summers is known as:
(a) Kaal Baisakhi (b) Loo (c) Trade Winds (d) Mango Showers
Answer: (b) Loo
(iii) Which one of the following causes rainfall during winters in north-western part of India?
(a) Cyclonic depression (b) Western disturbances (c) Retreating monsoon (d) South West monsoon
Answer: (b) Western disturbances
(iv) Monsoon arrives in India approximately in:
(a) Early May (b) Early July (c) Early June (d) Early August
Answer: (c) Early June
1. During winter, north-east trade winds blow from land to sea across most parts of India, remaining dry.
2. However, these winds cross over the Bay of Bengal before hitting the Tamil Nadu coast.
3. As they gather moisture from the Bay of Bengal, they bring heavy rainfall to the Coromandel coast during October and November.
1. Rhythm of Seasons: Although landscape and temperature vary across India, the monsoon provides an interconnected seasonal pattern.
2. Agricultural Reliance: Farmers throughout India eagerly await monsoon rains to initiate sowing operations.
3. Cultural Integration: Numerous traditional Indian festivals, songs, and celebrations revolve around the arrival and cycle of monsoon rains.
Read More & Chapter Resources
These short notes are designed for quick revision. Read the main points once, then use the related material below to practise the same chapter. Revising a concept and checking it with questions can make your preparation more focused.