Atmosphere pollution sources

Air quality, concern about deposition of toxic chemicals, 135 Air quality in Mexico City atmospheric pollution, sources, 150r carbon monoxide standards, 156r,157/ fuel consumption in metropolitan area and Mexico, 153r,154 fuel quality, 155... 

The sensibility of lichens to atmospheric pollution was demonstrated in the last two decades in various international and national publications. Recent studies showed that the survey of a large territory with lichens turns identification of atmospheric pollution sources possible (Sloof, 1993). The use of lichens is the only possibility to go through a large scale monitoring, which otherwise would be done with an enormous amount of air samplers and samples. Response of lichens to the environment is being studied through modelling very recently in our Institute (Reis et al., 1999). This is made with lichen transplants whose response to airborne particulate matter, and total deposition is followed experimentally. 

To these technological constraints are added an increasing preoccupation with limiting the evaporation losses that are an important source of atmospheric pollution (Me Arragher et al., 1990). 

Both receptor and analytical air quahty models have proven to be powerful tools for understanding atmospheric pollutant dynamics and for determining the impact of sources on air quahty. 

Under low-dose conditions, forest ecosystems act as sinks for atmospheric pollutants and in some instances as sources. As indicated in Chapter 7, the atmosphere, lithosphere, and oceans are involved in cycling carbon, nitrogen, oxygen, sulfur, and other elements through each subsystem with different time scales. Under low-dose conditions, forest and other biomass systems have been utilizing chemical compounds present in the atmosphere and releasing others to the atmosphere for thousands of years. Industrialization has increased the concentrations of NO2, SO2, and CO2 in the "clean background" atmosphere, and certain types of interactions with forest systems can be defined. 

In Gaussian plume computations the change in wind velocity with height is a function both of the terrain and of the time of day. We model the air flow as turbulent flow, with turbulence represented by eddy motion. The effect of eddy motion is important in diluting concentrations of pollutants. If a parcel of air is displaced from one level to another, it can carry momentum and thermal energy with it. It also carries whatever has been placed in it from pollution sources. Eddies exist in different sizes in the atmosphere, and these turbulent eddies are most effective in dispersing the plume. 

Mixing height The height above an internal or external pollutant source within which emitted pollutants are dispersed and mixed with the surrounding atmosphere. In meteorological terms, this is the area below the inversion layer. 

Table I. Sources of Atmospheric Pollution in 1989 (metric tons per year)...

Acid rain. Natural (unpolluted) precipitation is naturally acidic with a pH often in the range of 5 to 6 caused by carbonic acid from dissolved carbon dioxide and sulfurous and sulfuric acids from natural emissions of SO and H2S. Human activity can reduce the pH very significantly down to the range 2 to 4 in extreme cases, mainly caused by emissions of oxides of sulfur. Because atmospheric pollution and clouds travel over long distances, acid rain is not a local problem. The problem may manifest itself a long way from the source. Problems associated with acid rain include ... 

The unique appearance of an infrared spectrum has resulted in the extensive use of infrared spectrometry to characterize such materials as natural products, polymers, detergents, lubricants, fats and resins. It is of particular value to the petroleum and polymer industries, to drug manufacturers and to producers of organic chemicals. Quantitative applications include the quality control of additives in fuel and lubricant blends and to assess the extent of chemical changes in various products due to ageing and use. Non-dispersive infrared analysers are used to monitor gas streams in industrial processes and atmospheric pollution. The instruments are generally portable and robust, consisting only of a radiation source, reference and sample cells and a detector filled with the gas which is to be monitored. 

Meybeck, M. 1993. Riverine transport of atmospheric carbon sources, global typology and budget. Water, Air, and Soil Pollution, 70, 443-463. 

Water Reclamation Works by their very nature can, at times be the source of unpleasant odorous emission. The odour-intensive compounds (osmogenes) which make up these emissions are believed to arise mainly as the decomposition products of carbohydrates and proteins. The breakdown of this waste material proceeds by aerobic and anaerobic processes at various stages of the treatment plant. Atmospheric pollution of this nature frequently results in complaints from members of the public either resident, or perhaps employed in the vicinity of such works. In order to confirm or deny that a reclamation works is responsible for a particular nuisance and, if possible to identify the causal agents it was decided that the Authority should have the capability of analysing for odorous and other polluting constituents of the atmosphere. This paper describes the progress made towards this objective and summarises the experience gained with a procedure in use. There are two principle approaches available for the analytical classification of odorous emissions -... 

The wavelength-dispersive x-ray spectroscopy method (ASTM D6376) provides a rapid means of measuring metallic elements in coke and provides a guide for determining conformance to material specifications. A benefit of this method is that the sulfur content can also be used to evaluate potential formation of sulfur oxides, a source of atmospheric pollution. This test method specifically determines sodium, aluminum, silicon, sulfur, calcium, titanium, vanadium, manganese, iron, and nickel. 

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