By the year 2020, in India alone, the energy demand is expected to increase by 300% from the present level. If urgent prevention and control measures are not put in place from now, the SO₂ emissions, as per TERI estimates, are expected to shoot-up more than the energy demand! In fact the model simulation shows a possibility of 315 % increase in SO₂ emissions over present levels. Hence, even though the sulphur deposition levels in much of India today are below the critical levels for acid rain, by the year 2020 the picture will be painfully different, if immediate mitigative steps are not taken now.

  Indian scenario :

Like China, in India too the main threat of an acid rain disaster springs from our heavy dependence on coal as a major energy source. Even though Indian coal is relatively low in sulphur content compared to the nature of coal reserves of other countries like China, what threatens to cause acid rain in India is the concentrated quantity of consumption, that is expected to reach very high levels in some parts of the country by 2020. As energy requirements in India are growing rapidly in tune with the growing economy, coal dependence in the country is expected to grow threefold over the current level of consumption, making the clouds of acid rain heavier over many highly sensitive areas in the country like the northeast region, parts of Bihar, Orissa, West Bengal and coastal areas in the south. Already the soils of these areas have a low pH value, which acid rain will aggravate further making them infertile and unsuitable for agriculture. The GREEN India 2047 project of TERI has estimated that India is already losing between 11% to 26% of agricultural output on account of soil degradation. Acid rain would only increase this figure significantly. The prospect of increasing consumption of coal in Asia makes the acid rain threat even more real than ever. Possible options for mitigation are: radical improvements in energy efficiency, a switchover to low sulphur fuels like natural gas, greater use of renewables, major cut-down and removal of sulphur from crude oil distillates like diesel, fuel oil, etc., and finally, the widespread use of state-of-the-art pollution control devices in all polluting sectors of the economy. As experience stands in Europe and north America, the threat of acid rain was severely dealt with in these regions through heavy spending on SO2 abatement technologies and rapidly cutting down the dependence on coal by shifting to natural gas and nuclear energy. But, action in these regions came only after a considerable amount of ecological damage. In the 1960s, fish populations in the Scandinavian countries were showing a rapid decline as a result of acid rain. The infamous forest dieback in some parts of central Europe was also from acid rain. Thus, experience from elsewhere bears out clearly enough that the whole problem as it confronts India needs proactive handling.  

     Conclusion :

         The issue of rapidly growing SO₂ emissions, the resultant sulphur deposition and the threat of acid rain in many areas of Asia is a transboundary problem involving many countries, and, therefore, its solution calls for regional initiatives. In Europe, the worsening situation of acid deposition from many countries in ‘70s and the related concerns about the pollution being carried over long distances, led to the signing of an international agreement in 1979, called "The Convention on Long-Range Transboundary Air Pollution". The signing of subsequent protocols led to binding commitments from European countries to limit and reduce their transboundary emissions of air pollutants. The worsening crisis of a long term acid-rain catastrophe in Asia, in the very near future, surely calls for urgent moves towards a similar agreement and binding protocols between the nations exposed to this threat in the not too distant future. And the action must begin now, as experience shows that all international agreements with binding commitments take long to bear fruit