Question Q.17GS1GS1

The Indian monsoon is a complex phenomenon influenced by various climatic factors. Critically examine the role of oceanic and atmospheric factors in determining the intensity and distribution of monsoon rainfall in India.

Main Body

Indian monsoon is the lifeline of India since it brings 80% of seasonal rainfall in the country. Yet it remains a complex phenomenonSudden onset, Break in between, Spatial & temporal variation, Retreat, Multifactorial dependence.

Role of oceanic factors:

a) Indian ocean dipole (IOD):

[Diagram showing BoB (Cold), Arabian Sea (Hot), with positive IOD showing more rainfall and negative IOD showing less rainfall]

b) El Niño & La Niña:

[Diagram showing El Niño event causes drought-like situation in Indian monsoon]

HP----[cold]----LP [Peruvian Coast]

East Australia LP↑----↑HP [Peruvian Coast]

La Niña eventcauses high rainfall in India

[Fig] Triple Dip La Niña2020, 21 and 22

Role of Atmospheric factors:

1Subtropical westerly Jet stream (STWS)

[Diagram showing STWS position]

Northern Branch

Southern Branch

For more rainfallSouthern Branch of STWS should be about Indian subcontinent.

2Somali Jet stream & Tibetan Easterly Jet stream (TEJS):

[Diagram showing Tibetan (LP) (Tibetan Easterly) TEJS and Somali get stream]

Somali get streamTEJS drives more rainfall

3Fluctuation of ITCZ

downwards → break in North India,

upwards → most exalted in Northern plains.

4Monsoon Disturbances

cause more rainfall during monsoons.

[Diagram showing monsoon system interactions]

Note from first page (overlapping context about rare earth elements):

4Truncheir: long, narrow & deep fissures, related to Mariana trench

5Abyssal plains: is most extensive plateaus, associated with landforms like mounts, buyots.

6Mid oceanic ridges: is volcanic eruptions due to plate spreading associated with divergent plate boundaries.

Significance:

(1) Crust formation: is newer formed and old is concerned

(2) Economic significance: is Banks→ fishing ground [by] Grand bank geography, is Tourism: continental shelf by water sports, scuba diving

(3) Polymetallic nodules and rare earth minerals

(4) Trenches: is helps in deep-sea dredging projects

(5) Mid oceanic ridges: is volcanism, earth material & formation

312 words12 paragraphs8 bullet points

Diagram

Multiple diagrams showing: 1) El Niño and La Niña effects on pressure systems and rainfall; 2) Position of subtropical westerly jet streams (Northern and Southern branches); 3) Somali jet stream and Tibetan Easterly jet stream interaction; 4) ITCZ fluctuation effects

Comprehensive coverage of multiple oceanic and atmospheric factors
Good use of diagrams to illustrate complex phenomena
Connection to real climatic events (El Niño, La Niña, Triple Dip La Niña)

Open original scan

Page 44

Topper

Abhimanyu Malik

AIR 602023

Subject & Paper

GS1GS1

Topic

Salient features of World's Physical Geography

Indian monsoon and climatic factors

Role of oceanic and atmospheric factors

Writing Stats

312

Total words

Paragraphs

Bullets