Acid rain: past, present, and future
During 1970s, acid rain had devastated several regions of North America and Western Europe. Since then counter measures implemented in these regions have gradually brought the problem under some control. But has the world nullified what was once a very strongly perceived threat of acid rain? Far from it; studies conducted in recent years show that acid rain is now as severe a threat to the developing world, especially India and China, as it was earlier to some of the developed countries. Even the latter have only partially recovered from the earlier episodes of excessively acidic rain and still have a long way to go. The purpose of this review is to call attention towards the still very real threat of acid rain in the context of its past and the present. This paper recapitulates the definition of acid rain, traces its history, and identifies its origins. It then discusses the impact of acid rain, especially the trans–national and trans–regional issues associated with it. The prognostics for developing countries are highlighted. The measures to control and prevent acid rain are then recapitulated.
Keywords: acid rain, global warming, sulphur oxides, nitrogen oxides, formic acid, biota, buildings, developing countries