Increased concentration of greenhouse gases in atmosphere and consequent global warming along with the activities of natural phenomena like El Nino are the major cause of environmental degradation and climate change. Climatic factors and natural resources like sunshine, ozone layer, life supporting atmosphere gases and water resources are under constant pressure. Global temperatures are increasing, monsoon cycles are becoming erratic and environmental degradation is threatening ecosystems in various climatic zones. These disturbances are resulting in erratic and deficit monsoons. These developments are affecting agricultural production and economy of the country. Asia and particularly the Indian subcontinent are getting most of the brunt.
Excessive carbon emission from manufacturing plants, power generating units and transport vehicles is polluting environment and causing global warming. Increased concentration of greenhouse gases in earth’s atmosphere and ensuing global warming are affecting ecosystems in various climatic zones of world including Arctic zone that influences the world’s climate in a major way. The process of climate change is in a state of flux and it is difficult to foretell the period of its stabilisation.
The climate change effect in India is becoming more pronounced with increasing summer temperatures, shrinking of winter season, delayed monsoon arrivals and their early withdrawals. Subtropical India is the most affected region.
India receives most of its rainfall from southwest monsoon between June and September. The pattern and periodicity of this monsoon are becoming erratic and uncertain. A decade wise review of rainfall data since 1951 to 2000 reveals an increasing number of drought years (Agricultural Research Data Book 2014, IASRI-ICAR). Even between 2001 and 2014, it has rained less than normal in 10 years out of a total of 14. This further indicates the trend of climate change.
Changing Cropping Patterns
Climate change effect is now visible in different regions of the country through a change in some of the major cropping patterns. Farmers in the eastern districts of Uttar Pradesh and parts of Bihar are at least partially replacing wheat with winter maize, and summer pearl millet (Bajra) has occupied large areas in central and western Uttar Pradesh due to change in the temperature regime. Whereas the receding monsoon rains have compelled farmers in parts of peninsular India to replace some of rice area with maize crop. Industrial demand for maize may also be a reason. Based on these changes in cropping patterns, the agricultural research centres across the country have initiated research programmes to study the effect of climate change on various aspects of crop production and to evolve a suitable technology for the changed environment.
Ecological disturbances brought about by global warming and natural weather forming systems are resulting in unusual and erratic monsoon. There were heavy and unusual rains during Rabi season (winters) of 2014-15, damaging wheat, rapeseed and mustard, pulses and potato crops in large parts of north India. It rained intermittently all through the winter months from December 2014 through April 2015. This inclement weather resulted in a fall in foodgrains production of 2014-15 to the extent of 1.73 percent in rice, 1.21 percent in wheat and 1.38 percent in pulses as compared to the production of same crops in 2013-14 (source-GOI). The record foodgrains production of 2013-14 of 265.04 million tonne was reduced to 252.68 million tonne in 2014-15 due to the above mentioned weather abnormalities.
India’s foodgrains production and agricultural economy are poised for a setback as a result of the weak southwest monsoon in 2015-16. This has happened on the heels of an inclement weather in the Rabi season (winters) of 2014-15 which had damaged major crops of rice, wheat, pulses and oilseeds with an overall loss in the production of foodgrains to the extent of around 4 percent in 2014-15 as compared to the previous agricultural year.
Southwest monsoon which provides most of India’s rainfall during June-September period arrived late by about two weeks in 2015-16. Monsoon was weak and erratic all through the season. Entire Indo-gangetic plains along with western and central Uttar Pradesh, parts of eastern India, central India and even parts of south India and most of Maharashtra received below normal rainfall during main monsoon months of 2015-16. The monsoon rains were excessive in some parts of desert districts of Rajasthan and Gujarat as it rained heavily there in a short span. In Kerala, where it usually rains substantially, the arrival of monsoon was late.
The total net area sown in India is estimated at 141.58 million ha and net irrigated area is 63.60 million ha (IASRI-ICAR 2014). Based on this data, the rainfed area in the country comes to 77.48 million ha, which is 55.1 percent of the net area sown. The rainfed area is most vulnerable in the drought years as the situation is being faced in 2015-16. Almost two-third of the country is rainwater deficit in 2015-16 monsoon months and crops in the rainfed areas have suffered. Crops in irrigated areas though have not suffered much, but their cost of production has gone high due to the additional expenditure incurred on irrigation. This is likely to raise the prices of foodgrains, vegetables and other agricultural commodities. Food security of Below Poverty Line (BPL) masses and overall agricultural economy may as well get a setback.
Rainfed rice crop will be affected adversely in northeast and eastern India including West Bengal, Bihar and eastern Uttar Pradesh. This crop will also be affected in Maharashtra, central and south India. Since the water requirement of maize, coarse cereals, pulses and oilseeds is comparatively less, their production will be affected to a lesser degree. It will be wise to increase area of pulses and oilseeds in rainfed regions of the country instead of rainfed wheat in the Rabi season of 2015-16. Also the soil and water conservation measures like mulching, use of short duration crop varieties and water saving devices e.g. drip irrigation and water harvesting methods should be taken on campaign basis. Practices of watershed management need to be popularised in all regions of the country.
The frequent weather abnormalities as experienced in 2014-15 and in 2015-16 and their effect on crop production are a cumulative result of climate change caused by the global warming. India is taking these developments seriously and has started acting accordingly. The country has already reduced its carbon emission by 12 percent. It has decided to reduce it to 35 percent by 2030. Other countries like the United States has committed for a 32 percent cut in its carbon emission by 2030. The world community will be watching the proceedings of this convention with great hope and anxiety.
(The author is the former vice chancellor of GB Pant University of Agriculture & Technology, Pantnagar)