Context:
The southwest monsoon rainfall, 7% more than normal, has started to withdraw. The India Meteorological Department (IMD) said that the system had begun retreating from parts of southwest Rajasthan and Kutch.
- The southern peninsula and central parts have had the bulk of the excess at 29% and 33%, respectively.
Relevance:
GS I- Indian Geography
Dimensions of the Article:
- What is Monsoon?
- Causes of Monsoon
- Importance of Monsoon for India
What is Monsoon?
- Monsoon connotes the climate associated with a seasonal reversal in the direction of winds. India has a hot monsoonal climate which is the prevalent climate in the south and southeast Asia.
- The Indian summer monsoon typically lasts from June-September with large areas of western and central India receiving more than 90% of their total annual precipitation during the period, and southern and northwestern India receiving 50%-75% of their total annual rainfall.
- Overall, monthly totals average 200-300 mm over the country as a whole, with the largest values observed during the heart of the monsoon season in July and August.
Causes of Monsoon
- During the summer months, sunlight heats the surfaces of both lands and oceans, but land temperatures rise more quickly due to a lower heat capacity.
- As the land’s surface becomes warmer, the air above it expands and an area of low pressure develops.
- Meanwhile, the ocean remains at a lower temperature than the land and so the air above it retains a higher pressure.
- Since winds flow from areas of the high-pressure area to low, this deficit in pressure over the continent causes winds to blow in an ocean-to-land circulation (a sea breeze).
- As winds blow from the ocean to the land, moist air is brought inland. This is why summer monsoons cause so much rain.
Importance of Monsoon for India
The Monsoon is one of the most important single variables in the Indian economy as a good monsoon can reduce the burden on the government, while a bad one can make it spend more.
Positive effects of Monsoon
- The agricultural prosperity of India depends very much on time and adequately distributed rainfall. If it fails, agriculture is adversely affected particularly in those regions where means of irrigation are not developed.
- Regional variations in monsoon climate help in growing various types of crops.
- Regional monsoon variation in India is reflected in the vast variety of food, clothes and house types.
- Monsoon rain helps recharge dams and reservoirs, which is further used for the generation of hydroelectric power.
- Winter rainfall by temperate cyclones in north India is highly beneficial for Rabi crops.
Negative effects of Monsoon
- Variability of rainfall brings droughts or floods every year in some parts of the country.
- Sudden monsoon burst creates a problem of soil erosion over large areas in India.
- In hilly areas, sudden rainfall brings landslide which damages natural and physical infrastructure subsequently disrupting human life economically as well as socially.
-Source: The Hindu
