Effects of Pollutants on the Atmosphere

Air pollutants reach receptors by being transported and perhaps transformed 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 atmosphere. 

Effects of Pollutants on the Chemistry of the Atmosphere, Hydrosphere, and Lithosphere... 

An important effect of air pollution on the atmosphere is change in spectral transmission. The spectral regions of greatest concern are the ultraviolet and the visible. Changes in ultraviolet radiation have demonstrable adverse effects e.g., a decrease in the stratospheric ozone layer permits harmful UV radiation to penetrate to the surface of the earth. Excessive exposure to UV radiation results in increases in skin cancer and cataracts. The worldwide effort to reduce the release of stratospheric ozone-depleting chemicals such as chlorofluorocarbons is directed toward reducing this increased risk of skin cancer and cataracts for future generations. 

HEINES, T.S., L.K.PETERS An analytical investigation of effect of a first order chemical reaction on the dispersion of pollutants in the atmosphere. Atmospheric Environment 7 (1972) S. 153-162. 

Galvez, N. Barr6n,V. Torrent,. J. (1999 a) Effect of phosphate on the crystallization of hematite, goethite, and lepidocrodte from ferrihydrite. Clays Clay Miner. 47 304-311 Gancedo, J.R. Grada, M. Marco, J.F. Pala-dos, J. (1988) Comparative Mossbauer and SEM study of the corrosion reaction of iron and weathering steel in SO2 polluted atmospheres. Hyperfine Interactions 41 637-640... 

The last two decades have seen some spectacular achievements in analytical science the placing of the environmental revolution on a sound basis by the routine determination of p.p.m. or p.p.b. levels of pollutants in the atmosphere, hydrosphere and biosphere the routine testing of athletes and race horses for traces of stimulants the remote analysis of the surface of the Moon and Mars and the atmosphere of Venus, etc. It has also been a period when the normal criteria for acceptable limits of impurities has dropped from the level of per cent to p.p.b., when non-destructive testing has become routine and when samples can be so small that even destructive methods of analysis scarcely have a deleterious effect on bulk of the material from which the sample is taken. In short, the nature of analysis has changed greatly. 

Generally, it is necessary to carry out a simultaneous solution of the coupled equations of mass, momentum, and energy to account properly for the changes in T, q, and Uj and the effects of the changes in each of these variables on each other. In considering air pollution models, however, it is reasonable to assume that the presence of pollutants in the atmosphere does not affect the meteorology to any detectable extent thus, the equations of continuity for contaminant species can be solved independently of the coupled momentum and energy equations. Nevertheless, despite this simplification, solution of the coupled momentum... 

The effect of CO on the rate of oxidation of NO has been investigated. Adding CO enhances the oxidation of NO in the presence and absence of reactive hydrocarbons. However, since CO concentrations required to achieve this conversion are higher than those usually present in polluted atmospheres, this work suggests that ambient levels of CO do not affect photochemical smog formation. 

The literature also indicates that while it is felt, by some, that acid precipitation does have an adverse effect on the performance of building materials, no work apparently is being done to investigate these effects. Ashton and Sereda (24) report that "Monitoring of the concentration of pollutants in the atmosphere and in rain is done by various government agencies in many countries, but little effort is directed to the study of their effect on building materials, particularly that of acidic components in rainwater."... 

A further study of the transport of aerosol pollution in die troposphere in relation to die actual optical-microphysical properties of aerosols, determined by the mediod of multiwave lidar sensing of atmosphere, allows the identification with high confidence of the various sources of aerosols. The effectiveness of the pollutants transport under equal conditions is determined by the lifetimes of pollutants in the atmosphere, which in turn depend on the character of the surface over which the air masses flow. 

Because of the catalytic effect of some impurities, the atmospheric ozone equilibrium is very sensitive to pollution of the atmosphere. Therefore, taking into account the role of ozone as a protective shield to UV-damaging, air pollution could become a serious danger for all biological systems living on the earth16. ... 

The study of the chemical composition of precipitation is of interest for the evaluation of many scientific and practical problems. Thus, a knowledge of the chemical composition makes it possible to evaluate the degree of air pollution, the sink terms in the atmospheric cycle of aerosol particles and water soluble gases, the corrosiveness of atmospheric waters and the effect of precipitation on the material balance of soils, waters and vegetation. For these reasons, many precipitation analyses have been done, mostly in the last three decades. In this book only those works are mentioned in which an extensive network were (or are) operated, as in the American, Swedish and Soviet programs. 

We are familiar with the use of ascorbic acid in pharmaceutical preparations. Although it is often found as the pure compound, in most cases it is present with a wide variety of other substances, which are often present simply to make the vitamin more palatable. However, much ascorbic acid is used for less well-known purposes. Much research has been carried out on the effects of ascorbic acid on various aspects of plant growth. It has been found to have effects upon germination and root growth. Spraying with ascorbic acid has been found to be effective in the protection of plants against the worst effects of ozone in the atmosphere produced by photolytic action on polluted... 

Fig. 3.39. Schematic illustration of the effect of pollutants on water quality in a re cipient. 1 — pollutants from the atmosphere, 2 — municipal wastewaters, 3 — sewers, 4 — industrial wastewaters, 5 — surface run-off, 6 — sul>surface run-off, 7 — contribution from non-inhibited areas, 8 — waste depots 8a — municipal, 8b — communal, 8c — sludge from wastewater treatment plants, 9 — agriculture and forestry 9a — animal production and natural fertilizers, 9b — industrial fertilizers and pesticides... 

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