Monsoons are mainly seasonal winds that reverse their direction according to the change in season. The monsoons starts its journey from the sea to the land in summers and from land to the sea during winters, hence, are a double system of seasonal winds. The duration of the monsoon lies between 100and 120 days initiating from early June to mid-September. At the time of its arrival, the normal rainfall increases suddenly and continues constantly for several days, which is known as the “burst” of the monsoon.
Mechanism of monsoon
- Due to Sun, there is differential heating of land and water.
- The Intertropical Convergence Zone or ITCZ shifts over Ganga plains during the Summer.
- The high-pressure area, east of Madagascar affects the monsoon.
- Due to strong vertical air currents and formation of high pressure over Tibetan plateau, the plateau gets intensely heated during the summer.
- Southern Oscillation affects the monsoon.