Indian climatology: What is the most plausible explanation for the location of the Thar Desert in western India? Evaluate key causes that suppress rainfall over Rajasthan and adjoining areas (wind direction, topography, and pressure systems). Choose the best explanation.
General Knowledge
Indian Geography
Difficulty: Medium
Choose an option
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AAlignment of the Aravalli Hills nearly parallel to the SW monsoon winds, offering little orographic lift; subsiding air in the subtropical high and continentality limit rainfall
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BCold ocean currents along the Gujarat–Rajasthan coast cool and dry the air strongly
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CPersistent rain shadow cast by the Himalayas directly over Rajasthan
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DHigh altitude of western India prevents moisture intrusions
Answer
Correct Answer: Alignment of the Aravalli Hills nearly parallel to the SW monsoon winds, offering little orographic lift; subsiding air in the subtropical high and continentality limit rainfall
Explanation
Key factors
- Aravalli alignment: The SW monsoon approaches mostly parallel to the Aravallis, producing little orographic uplift and thus scant rainfall.
- Subtropical high subsidence & continentality: Western India often lies under descending, dry air with long distance from moist sources.
Why others are weakerThere is no major cold current off Rajasthan; the Himalayan rain shadow is more pronounced immediately north of the range, not over Rajasthan; altitude is not the limiting factor.
Final AnswerAravalli parallelism + subsidence/continentality (option A).