Acid rain definition

Acidity, definition in relation to possible ecosystem responses, 38,41 Acid precipitation, role of HO, 75 Acid rain... 

Informed debate and decisions on such important matters as the depletion of the ozone layer, acid rain and the quality of waterways all depend on the data provided by analytical chemists. Forensic evidence also often depends on chemical measurements. National and international trade are critically dependent on analytical results. Chemical composition is often the basis for the definition of the nature of goods and tariff classification. In all of these areas not only is it important to get the right answer but it is essential that the user of the results is confident and assured that the data are truly representative of the sample and that the results are defendable, traceable and mutually acceptable by all laboratories. 

Look again at Figure 26-10. As you can see, water cycles through the atmosphere, on Earth s surface, and under the surface. Can atmospheric processes affect the hydrosphere The answer is most definitely yes. Processes that take place in the atmosphere, such as the formation of acid rain, can have a direct impact on the hydrosphere. The interrelatedness of the components of the environment is an important concept to keep in mind as you explore Earth s water, beginning with the vast and mighty seas. 

It is probably true to say that the term environmental chemistry has no precise definition. It means different things to different people. We are not about to offer a new definition. It is clear that environmental chemists are playing their part in the big environmental issues—stratospheric ozone (C) () depletion, global warming and the like. Similarly, the role of environmental chemistry in regional-scale and local problems—for example, the effects of acid rain or contamination of water resources—is well established. This brief discussion illustrates the clear link in our minds between environmental chemistry and human beings. For many people, environmental chemistry is implicitly linked to pollution . We hope this book demonstrates that such a view is limited and shows that environmental chemistry has a much wider scope. 

It can be asked at this point what these results have to do with the economic effects of acid rain on materials. First, the baseline or world from which the acid-rain accounting is made is examined. In parallel with definitions used in the corrosion study, this is clearly a world in which man-made acid rain does not exist. However, unlike the case in the corrosion study, where a corrosion-free world can be imagined but cannot be realized... 

Give the definition of acid rain. Present the relative ranking of acid rain depending on pH values. 

Naturally, I can t know in detail how these risks were balanced in the minds of all participants in the political struggle over TOSCA, acid rain, or other issues. Whatever these internal considerations, however, the results usually show a definite pattern of swinging from one approach to facts and measurements to the other. A not unfamiliar pattern in the political system is that of initial fact and measurement manipulation and exploitation to stake out position, and later intelligent use to build reasonable positions after the fatigue and futility of adversary "fact" games have set in. A common variation is that of initial cooperative work with a common base of fact and measurement among technical colleagues, which switches to the adversary position when... 

The environment on which an oil and gas facility is exposed to is also a significant factor that affects corrosion. For example, pipelines are laid in the soil, above the soil, and across the sea. The nature of seawater is a contributor to corrosion depending on whether it is a saltwater or freshwater since either will definitely have a different effect on a facility. Also, above the sea or across or in the soil, environmental activities such as snow, dew, soil type, and temperature also contribute to the corrosion of an oil and gas facility over time, notwithstanding the possibility of acid rain in a heavily industrialized area. 

Reports by Wood and Bormann (1977), and Wood and Pennypacker (1976) show that pine needles are rather insensitive to simulated acid rain. When these results are compared with those for foliage of birch (Wood and Bormann, 1974), maple (Wood and Bormann, 1975), poplar and oak, the foliage from broadleaved trees is injured to a greater extent. These results suggest that the deciduous forests of eastern North America would be more sensitive to acid precipitation than the predominantly coniferous forests of Scandinavia. More experimentation is necessary to make more definitive comparisons between deciduous and coniferous plant species. 

In a strict definition acid rain refers to the wet precipitation of pollutants SO2/SO3 and N02/HN03 which have dissolved in cloud and rain droplets to form sulphuric and nitric acids. However/ the term has come to be more generally applied to include dry precipitation of the gaseous pollutants and their gaseous and particulate derivatives. 

All rain Is acidic but not aii rain is acid rain. Scientific terms have a precise definition. Does scientific vocabulary simply communicate our knowiedge in a neutral way or can it have vaiue-laden terminology ... 

FIGU RE 1.1 Illustration of the definition of environmental chemistry exemplified by the life cycle of a typical pollutant, sulfur dioxide. Sulfur present in fuel, almost always coal, is oxidized to gaseous sulfur dioxide, which is emitted to the atmosphere with stack gas. Sulfur dioxide is an air pollutant that may affect human respiration and may be phytotoxic (toxic to plants). Of greater importance is the oxidation of sulfur dioxide in the atmosphere to sulfuric acid, the main ingredient of acid rain. Acidic precipitation may adversely affect plants, materials, and water, where excessive acidity may kill fish. Eventually, the sulfuric acid or sulfate salts end up in water or in soil. 

The definition of environmental chemistry shown in Figure 1.1 could very well be illustrated with nitrogen oxides, NO and NO2, emitted to the atmosphere. What would be the sources of these gaseous nitrogen oxides Which secondary air pollutant would they form interacting with volatile hydrocarbons in the sunlight Could acid rain result from these oxides and, if so, what would be the formula of the acid ... 

Pines. Calorimetric studies of growth rates and temperature responses have not been employed to examine pine trees. Two studies were conducted to analyze effects of air pollutants on the respiration properties of Ponderosa and Jeffrey pine needles. Bower [104] used one-cm needle segments and demonstrated a correlation between the extent of ozone damage, measured as the number of lesions on the needles, and isothermal metabolic heat rates. He also measured increases in metabolic heat rates resulting from acid and nitrate deposition on the needles. Momen et al. [105] conducted a more controlled study of acid rain and ozone effects on Ponderosa pine with defined applications to plantation grown plants. In seedlings, metabolic heat rates increased in response to ozone and combinations of ozone and acid rain. Mature tree metabolic activities showed no response to ozone, acid, or combinations of the two. No studies were made to determine whether metabolic efficiencies were altered by these treatments. Thus the results show that calorimetry can be used to monitor pollutant effects on trees, but more definitive experiments must be done to identify how the ob.served responses relate to growth and survival of the trees. 

The scientific panel that the White House handpicked to carry out the review sent the President a report that again strongly recommended action on acid rain. Under the chairmanship of William Nierenberg, Director of the Scripps Institute of Oceanography, the panel concluded that, "It is in the nature of the acid deposition problem that actions have to be taken despite incomplete knowledge. .. If we take the conservative point of view that we must wait until the scientific knowledge is definitive, the accumulated deposition and damaged environment may reach the point of irreversibility. . ... 

Acid rain was portrayed by the opponents of regulation as largely a problem of definition. "The term acid rain is a redim-dancy," wrote Carolyn Curtis for the Electric Power Research Institute, the research arm of the electric utilities. "By definition, natuial lain is somewhat acidic. .. So by all rights we should have been saying for years, It s acid raining outside. .." (emphasis original). 

Johnson, C. A., and L. Sigg (1985), "Acidity of Rain and Fog Conceptual Definitions and Practical Measurements of Acidity", Chimia 39, 59-61. 

It should be kept in mind that, in spite of these major variations in the CO2-carbonic acid system, virtually all surface seawater is supersaturated with respect to calcite and aragonite. However, variations in the composition of surface waters can have a major influence on the depth at which deep seawater becomes undersaturated with respect to these minerals. The CO2 content of the water is the primary factor controlling its initial saturation state. The productivity and temperature of surface seawater also play major roles, in determining the types and amounts of biogenic carbonates that are produced. Later it will be shown that there is a definite relation between the saturation state of deep seawater, the rain rate of biogenic material and the accumulation of calcium carbonate in deep sea sediments. 

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