Page 319 - Fundamentals of Air Pollution 3E

18

The Meteorological Bases

of Atmospheric Pollution

Air pollutants reach receptors by being transported and perhaps trans-
formed in the atmosphere (Fig. 18-1). The location of receptors relative to
sources and atmospheric influences affect pollutant concentrations, and
the sensitivity of receptors to these concentrations determines the effects.
The location, height, and duration of release, as well as the amount of
pollutant released, are also of importance. Some of the influences of the
atmosphere on the behavior of pollutants, primarily the large-scale effects,
are discussed here, as well as several effects of pollutants on the atmo-
sphere.

I. VENTILATION

If air movement past a continuous pollutant source is slow, pollutant
concentrations in the plume moving downwind will be much higher than
they would be if the air were moving rapidly past the source. If polluted
air continues to have pollution added to it, the concentration will increase.
Generally, a source emits into different volumes of air over time. However,

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