The Indian Monsoon : Geography

The Indian Monsoon is a large-scale phenomenon that transports water and energy from the tropical seas to the landmasses of Southern Asia.

The monsoon, which is essentially the seasonal reversal in wind direction, causes most of the rainfall received in India and some other parts of the world. The primary cause of monsoons is the difference between annual temperature trends over land and sea.

N and 20° S. Go through the following facts to understand the mechanism of the monsoons in a better way:

1. The differential heating and cooling of land and water creates low pressure on the landmass of India while the seas around experience comparatively high pressure.
2. The shift of the position of Inter-Tropical Convergence Zone (ITCZ) in summer, over the Ganga plain, is also known as the monsoon-trough during the monsoon season.
3. The presence of the high-pressure area, east of Madagascar, approximately at 20°S over the Indian Ocean affects the Indian Monsoon.
4. The Tibetan plateau gets intensely heated during summer, which results in strong vertical air currents and the formation of low pressure over the plateau at about 9 km above sea level.
5. The movement of the westerly jet stream to the north of the Himalayas and the presence of the tropical easterly jet stream over the Indian peninsula during summer also impact the Indian Monsoon.
6. The changes in the pressure conditions over the southern oceans also affect the monsoons. The irregularly periodic variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean that affects the climate of the tropics and subtropics is known as Southern Oscillation or SO.