Environment, chemistry acid rain

Atmospheric emissions of sulphur dioxide are either measured or estimated at their source and are thus calculated on a provincial or state basis for both Canada and the United States (Figure 2). While much research and debate continues, computer-based simulation models can use this emission information to provide reasonable estimates of how sulphur dioxide and sulphate (the final oxidized form of sulphur dioxide) are transported, transformed, and deposited via atmospheric air masses to selected regions. Such "source-receptor" models are of varying complexity but all are evaluated on their ability to reproduce the measured pattern of sulphate deposition over a network of acid rain monitoring stations across United States and Canada. In a joint effort of the U.S. Environmental Protection Agency and the Canadian Atmospheric Environment Service, eleven linear-chemistry atmospheric models of sulphur deposition were evaluated using data from 1980. It was found that on an annual basis, all but three models were able to simulate the observed deposition patterns within the uncertainty limits of the observations (22). 

Acid rain monitoring data in North America have been gathered by Environment Canada and stored in the National Atmospheric Chemistry (NatChem) Database, details of which can be found at www.airquality.tor.ec.gc.ca/natchem. Analysis of the deposition chemistry data has confirmed that wet sulfate deposition did indeed decline in concert with the decline in SO2 emissions in both eastern Canada and the... 

Taka Hiraishi obtained his Bachelor of Science (1966) and Masters of Science for Industrial Chemistry (1968) from Tokyo University in Japan. He joined the Ministry of Labour (Occupational Health and Safety Department) in April 1968 and moved to the newly-established Environment Agency in 1971, where he worked in the fields of offensive odours, acid rain, the ozone layer, hazardous wastes, hazardous chemicals and water pollution, till 1996. 

The term acid rain is commonly used to describe phenomena associated with both wet and dry deposition. The effects of man-made airborne substances on indoor surfaces are expected to be different from and less dramatic than those on outdoor surfaces. In the outdoor environment, both the species contained in the rain or fog droplets and the added influence of substances previously deposited on the surfaces by dry deposition will impact the surfaces. For very brief rain events, the surface concentrations of many species are likely to be substantial, due to the combined effects of accumulated dry deposition and the high concentrations of species that have been commonly associated with the early stages of a rain event. The available data indicate that roughly 70 percent of the total deposition is dry deposition. Hansen and Hidy (2), in their assessment of existing rain chemistry data, discuss the influence of geographical factors on pH and state that in western arid areas of the United States, soil-derived substances elevate the pH in the early stages of a rain event, while in the northeastern... 

Irwin JG, Williams NL. 1988. Acid rain Chemistry and transport. Environ Pollut 50 29-59. 

Clarke, A. G., and Radojevic, M., Oxidation of S02 in rainwater and its role in acid rain chemistry. Atmos. Environ. 21, 1115 (1987). 

The effect of industrial society on the environment is especially apparent in the problem of acid rain the underlying chemistry applies several principles of ionic equilibria. Acidic precipitation—rain, snow, fog, or dry deposits on particles—has been recorded in all parts of North America, the Amazon basin, Europe, including Russia, much of Asia, and even at the North and South Poles. Three major substances are involved ... 

Chemistry Links to the Environment relate chennistry to environmental topics such as global warming, radon in our homes, acid rain, and pheromones. 

The other major problems associated with fossil fuel use stem from the products of combustion. The chemical equations shown for fossil fuel combustion all produce cartxM dioxide and water. However, these equations represent the reactions under ideal conditions and do not account for impurities in the fuel, side reactions, and incomplete combustion. When these are taken into account, we can identify three major awiron-mental problems associated with the emissitxis of fossil fuel combustion air pollution, acid rain, and global climate change. We discussed acid rain in Chjpter 3 (see Chemistry in the Environment Acid Rain in Section 3.6). Here we will address air pollution and global climate change, which we first touched on in Section 4.1. 

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