Monsoon is a system of winds, whose main feature is the seasonal reversal of direction.
- Theory of differential heating of land and sea
In the summer season, there is
build up of temperature over the Indian landmass and when it becomes higher than the neighbouring sea, a sharp difference in pressure begins to exist between land and sea. Consequently, air begins to flow from the sea to the landmass that is from a region of high pressure to that of a lower one.
Thus southwest monsoon gets established.
Moisturised winds from the Indian ocean, Arabian sea and the Bay of Bengal bring rainfall over different parts of India. Besides, surface level winds, the upper atmospheric conditions also influence the South-West monsoon in India.
During winter, the landmass is colder than the sea and so airflow is in the opposite direction that is from land to sea. Direction of flow is from north to ocean in the south, which is called the
North-East Monsoon. Moisturised winds from the Indian ocean, Arabian Sea and the Bay of Bengal bring rainfall over different parts of India. Besides, surface level winds, the upper atmospheric conditions also influence the south-west monsoon in India.
