Investigation of alkaline nature of rain water in India

Increased industrialization and urbanization lead to the atmospheric acidit y which causes acid rain. However, in India, the nature of rain water has b een observed to be alkaline. The reason for alkaline nature of rain water i s found to be the buffering of acidity by soil-derived aerosols which are r ich in Ca. Over the Indian Ocean where concentrations of soil dust are negl igible, the acid rain has been observed to be a common phenomenon during IN DOEX campaigns. In the Indian subcontinent, observations have indicated tha t rain becomes acidic when the buffering potential of rain water is weak. T he weak buffering potential may be due to less interference of soil dust, a cidic nature of soil or very high influence of industrial source.