Question 6Answer in 250 wordsGS1GS1

Explain the mechanism of the Indian monsoon. What role do El-Niño and La-Niña play in the development over the Indian subcontinent?

Introduction

Indian monsoon refers to the seasonal reversal of winds, oscillating pressure differentials between land and sea, system of sea and seasonal concentration of rainfall.

24 words

Main Body

Mechanism of Monsoon

1Classical Theory - The North-western region of India develops a low pressure, while ocean has high pressure, leading to inflow of moisture-laden winds

2Dynamic Theory - explains the role of movement of ITCZ over Northern India, due to sun's northward [illegible]

migration. Develop a low pressure due to water, the moisture laden winds be equatorial westerlies sees the equator and enter towards India.

3Modern Theory

(i) Jet Streamemergence of tropical energy in over peninsular India due to heating of Tibetan peninsula. Strengthens Indian monsoon.

Disappearance of subtropical weekly jetover Kharistansalps to develop a low pressure over N.W. Rajasthan.

(ii) Development of normal/Arabian U necessary high.

Role of El-Niño: Stronger Southern Oscillation

1El-Niño - Anomalous warming of Eastern Pacific → reversal of Walker cell → weakening of Indian monsoon.

2La-Niña → strengthening of trade winds → Anomalous cooling of Eastern Pacific, strengthening of Walker cell → strong Indian monsoon.

Therefore, Indian monsoon is a result of complex atmospheric-ocean interaction, that determine its arrival, frequency & strength.

180 words7 paragraphs

Diagram

Map showing coastal theory with HP (High Pressure) and LP (Low Pressure) zones marked

Structured approach with two theories
Clear definition provided
Diagram included for clarity

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Page 16

Topper

Ritika Chitlangia

Subject & Paper

GS1GS1

Topic

Important Geophysical Phenomena

Monsoons

Indian monsoon mechanism and ENSO

Writing Stats

204

Total words

Paragraphs