What to do about acid rain

An overview is presented of the problem of acid rain. During the last several decades, increasing fossil-fuel combustion in western Europe and the northeastern US, especially by power plants, has severely polluted local air. The solution has often been to construct taller smokestacks to disperse the emissions. Unfortunately, this allows pollutants to create problems on a broader geographical scale. At the same time, pollution-control devices have come into use to remove the ash from the emissions. But because ash is alkaline, removing it makes the acids stronger. Industry and transportation are the major sources of acid deposition. The problems involved in tracing acid to its sources are discussed. In addition, methods of reducing emissions are evaluated.