India is undergoing a major transition with changes in rainfall patterns leading to increased frequency of droughts, floods, heat waves amidst fear of a major water crisis in the years to come.
Relevance of rainfall in india :
The south-west (SW) monsoon (June to September), often referred to as the lifeline of India, contributes 75 percent to the annual rainfall in the country with some areas like Gujarat receiving more than 95 percent of its annual rainfall from the SW monsoon. The contribution of the pre-monsoon (March, April and May) and post-monsoon (October, November and December) rainfall is 11 percent. The SW monsoon plays a very important role in agriculture, water resources, power management and consequently the economy of the country but shows considerable variation in terms of onset, withdrawal and amount of rainfall leading to years of excess rainfall or droughts.
The average annual rainfall patterns over different parts of the country show that it ranges from less than 13 cm over Ramgarh in western Rajasthan to 984 cm in Mawsynram in Meghalaya. The rainfall pattern also influences the climate of the country which varies from humid northeast (with 180 days rainfall in a year) to arid Rajasthan (with less than 20 days rainfall in a year). Even the mean rainfall patterns for the country as a whole are variable with the mean monthly rainfall during July (289.2 mm) being highest, contributing about 24.4 percent of annual rainfall (1187.6 mm). The mean rainfall during August contributes about 22 percent of annual rainfall while that during June and September contribute 13.8 percent and 14.6 percent to the annual rainfall, respectively.
Rainfall in India is currently undergoing further changes due to climate change, leading to increasing instances of floods, droughts, making it important to study the trends in rainfall patterns to design better coping strategies for the future. Also, the Indian economy is still dependent on agriculture and the SW monsoon. Droughts and famines can prove to be lethal for the country.
Many of these changes are being triggered by climate change. Increasing urbanisation, deforestation, land use changes, pollution due to particulate matter seem to exacerbate these conditions affecting rainfall patterns in major ways. These will continue to influence not only the agriculture and economy but water resources and even the health and survival of populations in the long run.
While rainfall patterns are changing, heavy amounts of rain in shorter spans of time call for the need to have better adaptation strategies to cope with these changes. While there are areas that have less rainfall, it seems that droughts triggered in Maharashtra are more due to poor management and lack of equitable distribution of the available water resources, faulty cropping patterns such as the emphasis on water-guzzling crops like sugarcane etc.
Utilization of Rain water Resources:
With so much rainfall over short spans of time, we must focus on harvesting and storing as much water as possible and catching the rainwater where it falls besides making efforts at saving our environment by preventing deforestation, focusing on reforestation, identifying and protecting groundwater recharge areas, saving and making judicious use of available water resources.
( taken from an external source )