Question

Three factors which affect the mechanism of monsoon

Answer 1

upper air circulation, 
The difference in heating and cooling rates of land and water. Between the two, land gets hotter and colder faster,
The occurrence of snow over the Tibetan Plateau.

Answer 2

The phenomenon o monsoon refers to the seasonal reversal of winds. The offshore winds that blow from north - east direction are reversed into onshore south - western winds.
This phenomenon is based upon differential heating of land & ocean bodies. During summer in Indian subcontinent the large landmass gets heated up more rapidly than neighbouring areas. As a result, the air above the land expands & rises up. The moisture laden winds arrive on the western coast of Indian subcontinent from South to western side & cause heavy rainfall on windward side of western Ghats. The leeward side however receives little rain. Further, rain occurs in northern plains & north eastern parts of India with the branching of the monsoon.

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