Indian Monsoon

The monsoon is formed by several atmospheric and oceanic factors. In exams, combined causes give a better answer.

The monsoon trough draws rain bearing winds towards the plains. When its position changes, rainfall areas also change.

Heating of the Tibetan Plateau affects upper air circulation. Study it with the shifting of jet streams.

After crossing the Equator, winds turn to the right in the Northern Hemisphere. This explains the south westerly direction.

Change in upper air flow supports monsoon onset. Do not limit jet streams only to winter.

The northward shifted convergence zone forms a low pressure belt over north India. This monsoon trough is linked with rainfall.

The Somali jet can strengthen the Arabian Sea branch. Remember it as an example of low level wind flow.

The Himalaya blocks northward movement and the trough draws winds into the plains. This is the key reason in route based questions.

In Meghalaya, funnel shaped relief and uplift of moist winds cause heavy rainfall. Relief is as important as distance from sea.

Moist air rises after striking the mountains and gives rain. On the other side descending air becomes drier.

Parallel mountains do not lift winds effectively. Therefore rainfall remains low in Rajasthan.

During retreating monsoon, winds pick moisture from the Bay of Bengal and rain on the Tamil Nadu coast. Link it with southwest rain shadow.

The active rain belt changes with the position of the monsoon trough. Do not treat a break as complete end of monsoon.

As distance increases from east to west, winds lose moisture. This explains the rainfall gradient in the Ganga plain.

The side facing the Western Ghats receives more rain and the leeward side receives less. Check slope position in location comparison.

With seasonal change, land temperature falls and low pressure weakens. This begins monsoon withdrawal.

El Nino is linked with global air circulation and may weaken the monsoon. Its impact is not always identical.

Southern Oscillation is linked with pressure changes. Such indicators help in monsoon forecasting.

Thermal contrast in the Indian Ocean can affect monsoon winds and moisture. Study it under ocean monsoon links.

Sea temperature is linked with moisture supply and pressure systems. Oceanic signals are important in monsoon study.