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Regional and Global Effects
Most air pollutants contributing to acid deposition are generated at the
surface of the Earth and are deposited back to Earth by atmospheric processes
in the troposphere. However, as source regions expand regional and global
problems are beginning to emerge. A cloud of pollutant material has developed
across South Asia that is so thick and expansive that it is causing damage to
agriculture, weather patterns, and human health for the countries of
Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri
Lanka. A United Nations Environment Programme indicates that this mixture of
haze, ash, and acid particles from burning fossil fuels and agricultural
materials is estimated to have caused 37,000 premature deaths per year in the
mid 1990s. By blocking solar radiation to the ocean surface, the cloud may be
reducing evaporation and contributing to disruption of the monsoon system
causing large-scale changes in patterns of drought and flooding. The report
was compiled by a team of some 200 scientists. In addition to acidic materials,
soot emitted during combustion on large regional
scales is contributing to global and regional effects.
PREVIOUS: Effects of Acid Deposition