- acid rain
precipitation, as rain, snow, or sleet, containing relatively high concentrations of acid-forming chemicals, as the pollutants from coal smoke, chemical manufacturing, and smelting, that have been released into the atmosphere and combined with water vapor: harmful to the environment.[1855-60]
* * *Any precipitation, including snow, that contains a heavy concentration of sulfuric and nitric acids.This form of pollution is a serious environmental problem in the large urban and industrial areas of North America, Europe, and Asia. Automobiles, certain industrial operations, and electric power plants that burn fossil fuels emit the gases sulfur dioxide and nitrogen oxide into the atmosphere, where they combine with water vapour in clouds to form sulfuric and nitric acids. The highly acidic precipitation from these clouds may contaminate lakes and streams, damaging fish and other aquatic species; damage vegetation, including agricultural crops and trees; and corrode the outsides of buildings and other structures (historic monuments are especially vulnerable). Though usually most severe around large urban and industrial areas, acid precipitation may also occur at great distances from the source of the pollutants.
* * *form of precipitation containing a heavy concentration of sulfuric and nitric acids. The term is also commonly applied to snow, sleet, and hail that manifest similar acidification. Such precipitation has become an increasingly serious environmental problem in many areas of North America, Europe, and Asia (see video—>). Although this form of pollution is most severe in and around large urban and industrial areas, substantial amounts of acid precipitation may be transported great distances.The process that results in the formation of acid rain generally begins with emissions into the atmosphere of sulfur dioxide and nitrogen oxide. These gases are released by automobiles, certain industrial operations (e.g., smelting and refining), and electric power plants that burn fossil fuels such as coal and oil. The gases combine with water vapour in clouds to form sulfuric and nitric acids. When precipitation falls from the clouds, it is highly acidic, having a pH value of about 5.6 or lower. (The term pH is defined as the negative logarithm of the hydrogen ion concentration in kilograms per cubic metre. The pH scale ranges from 0 to 14, with lower numbers indicating increased acidity.) At several locations in the eastern United States and western Europe, pH values between 2 and 3 have been recorded. In areas such as Los Angeles, San Francisco, and Whiteface Mountain in New York, fog is often 10 or more times as acidic as the local precipitation.Precipitation and fog of high acidity contaminate lakes and streams; they are particularly harmful to fish and other aquatic life in regions with thin soil and granitic rock, which provide little buffering to acidic inputs. It also has been discovered that aluminum is leached from the soil in regions subjected to such acid precipitation, and that dissolved aluminum seems to be extremely toxic to aquatic organisms. All forms of acid precipitation have been found to damage various kinds of vegetation, including agricultural crops and trees, chiefly by inhibiting nitrogen fixation and leaching nutrients from foliage. In addition, these pollutants can corrode the external surfaces of buildings and other man-made structures; marble structures and statues are especially vulnerable to their damaging effects.The problem of acid rain has been mainly dealt with in two ways. Adherents to the “cost-sharing” principle believe acid rain is a regional problem that should be dealt with collectively by all countries affected by the problem. Supporters of the “polluter pays” approach highlight the actions and responsibility of the polluter, which they believe should pay for the damages caused by its habits and institutions.
* * *
Look at other dictionaries:
Acid rain — is rain or any other form of precipitation that is unusually acidic. It has harmful effects on plants, aquatic animals, and infastructure. Acid rain is mostly caused by human emissions of sulfur and nitrogen compounds which react in the… … Wikipedia
Acid Rain — Лучшие хиты Esham Дата выпу … Википедия
acid rain — n acid precipitation esp. in the form of rain … Medical dictionary
acid rain — n [U] rain that contains harmful acid which can damage the environment and is caused by chemicals in the air, for example from cars or factories … Dictionary of contemporary English
acid rain — noun uncount rain containing a high level of acid that can damage the environment. It is caused by pollution in the air … Usage of the words and phrases in modern English
acid rain — n. rain or other precipitation with a high concentration of acids produced by sulfur dioxide, nitrogen dioxide, and other such gases that result from the combustion of fossil fuels: it has a destructive effect on plant and aquatic life, buildings … English World dictionary
Acid rain — Acid rain. См. Кислотный дождь. (Источник: «Металлы и сплавы. Справочник.» Под редакцией Ю.П. Солнцева; НПО Профессионал , НПО Мир и семья ; Санкт Петербург, 2003 г.) … Словарь металлургических терминов
acid rain — ► NOUN ▪ rainfall made acidic by sulphur and nitrogen oxides from the industrial burning of fossil fuels … English terms dictionary
acid rain — noun rain containing acids that form in the atmosphere when industrial gas emissions (especially sulfur dioxide and nitrogen oxides) combine with water • Syn: ↑acid precipitation • Hypernyms: ↑air pollution * * * noun [noncount] : rain that… … Useful english dictionary
acid rain — /æsəd ˈreɪn/ (say asuhd rayn) noun highly acidic rain, caused by pollution in the atmosphere. Acid rain is formed when airborne pollutants from the burning of fossil fuels, and from industrial activities and vehicles emissions, as well as from… … Australian English dictionary