Urban Air Pollution

The effects of air pollution in the urban climates differ from those of the rural areas due to the influence of certain factors that are only present in the cities (OMS, 1988), like different superficial materials, wide variety of shapes and alignments of the structure of the city relative to the landscapes of non urbanized areas, great production of heat caused by heating systems, rapid superficial runoff of rain and great load of solid, liquid, and gaseous pollutants discharged in the air.

There is no single or direct approach for attacking the problem of air pollution in a given region. The diversity of polluting activities, the meteorological conditions, the topographical features and the urban spatial form make it extremely complex to evaluate the magnitude and causes of air pollution.

Although the amount of pollutants emitted to the atmosphere constitutes the origin of pollution, it is the distribution of their concentration that defines the areas of different levels of pollution. The meteorological  and topographical  aspects are key factors in the dispersion of these emissions and, therefore, the areas of higher level of pollution will not necessarily correspond with those with greater emissions to the atmosphere in a big city.

References

OMS; 1988. Evaluación epidemiológica de riesgos causados por agentes químicos ambientales. Generalidades y toxicología. Tomo I. Centro Panamericano, Ecología Humana y Salud, O.M.S., O.P.S.; Buenos Aires, Argentina.