Acid rain

Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). It can have harmful effects on plants, aquatic animals and infrastructure. Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids. Some governments have made efforts since the 1970s to reduce the release of sulfur dioxide and nitrogen oxide into the atmosphere with positive results. Nitrogen oxides can also be produced naturally by lightning strikes, and sulfur dioxide is produced by volcanic eruptions. Acid rain has been shown to have adverse impacts on forests, freshwaters and soils, killing insect and aquatic life-forms, causing paint to peel, corrosion of steel structures such as bridges, and weathering of stone buildings and statues as well as having impacts on human health.

Origins of acid rain
Processes involved in acid deposition (only SO2 and NOx play a significant role in acid rain).
Cloud formation from refinery in Curacao
Acid clouds can grow on SO2 emissions from refineries, as seen here in Curaçao.
External audio
"Whatever Happened to Acid Rain?", Science History Institute


"Acid rain" is a popular term referring to the deposition of a mixture from wet (rain, snow, sleet, fog, cloudwater, and dew) and dry (acidifying particles and gases) acidic components. Distilled water, once carbon dioxide is removed, has a neutral pH of 7. Liquids with a pH less than 7 are acidic, and those with a pH greater than 7 are alkaline. "Clean" or unpolluted rain has an acidic pH, but usually no lower than 5.7, because carbon dioxide and water in the air react together to form carbonic acid, a weak acid according to the following reaction:

H2O (l) + CO2 (g) ⇌ H2CO3 (aq)

Carbonic acid then can ionize in water forming low concentrations of carbonate and hydronium ions:

H2O (l) + H2CO3 (aq) ⇌ HCO3 (aq) + H3O+ (aq)

Unpolluted rain can also contain other chemicals which affect its pH (acidity level). A common example is nitric acid produced by electric discharge in the atmosphere such as lightning.[1] Acid deposition as an environmental issue (discussed later in the article) would include additional acids other than H2CO3.


The corrosive effect of polluted, acidic city air on limestone and marble was noted in the 17th century by John Evelyn, who remarked upon the poor condition of the Arundel marbles.[2] Since the Industrial Revolution, emissions of sulfur dioxide and nitrogen oxides into the atmosphere have increased.[3][4] In 1852, Robert Angus Smith was the first to show the relationship between acid rain and atmospheric pollution in Manchester, England.[5]

In the late 1960s scientists began widely observing and studying the phenomenon.[6] The term "acid rain" was coined in 1872 by Robert Angus Smith.[7] Canadian Harold Harvey was among the first to research a "dead" lake. At first the main focus in research lay on local affects of acid rain. Waldemar Christofer Brøgger was the first to acknowledge long-distance transportation of pollutants crossing borders from the United Kingdom to Norway.[8] Public awareness of acid rain in the US increased in the 1970s after The New York Times published reports from the Hubbard Brook Experimental Forest in New Hampshire of the harmful environmental effects that result from it.[9][10]

Occasional pH readings in rain and fog water of well below 2.4 have been reported in industrialized areas.[3] Industrial acid rain is a substantial problem in China and Russia[11][12] and areas downwind from them. These areas all burn sulfur-containing coal to generate heat and electricity.[13]

The problem of acid rain has not only increased with population and industrial growth, but has become more widespread. The use of tall smokestacks to reduce local pollution has contributed to the spread of acid rain by releasing gases into regional atmospheric circulation.[14][15] Often deposition occurs a considerable distance downwind of the emissions, with mountainous regions tending to receive the greatest deposition (because of their higher rainfall). An example of this effect is the low pH of rain which falls in Scandinavia.

In the United States

External audio
Gene Likens 2015 Mariel Carr
“Whatever Happened to Acid Rain?“, Distillations Podcast, Science History Institute
Bixi stele (wrapped), Harvard University, Cambridge, MA - IMG 4607
Since 1998, Harvard University wraps some of the bronze and marble statues on its campus, such as this "Chinese stele", with waterproof covers every winter, in order to protect them from corrosion caused by acid rain and acid snow[16]

The earliest report about acid rain in the United States was from the chemical evidence from Hubbard Brook Valley. In 1972, a group of scientists including Gene Likens discovered the rain that was deposited at White Mountains of New Hampshire was acidic. The pH of the sample was measured to be 4.03 at Hubbard Brook.[17] The Hubbard Brook Ecosystem Study followed up with a series of research that analyzed the environmental effects of acid rain. Acid rain that mixed with stream water at Hubbard Brook was neutralized by the alumina from soils.[18] The result of this research indicates the chemical reaction between acid rain and aluminum leads to increasing rate of soil weathering. Experimental research was done to examine the effects of increased acidity in stream on ecological species. In 1980, a group of scientists modified the acidity of Norris Brook, New Hampshire, and observed the change in species' behaviors. There was a decrease in species diversity, an increase in community dominants, and a decrease in the food web complexity.[19]

In 1980, the US Congress passed an Acid Deposition Act.[20] This Act established an 18-year assessment and research program under the direction of the National Acidic Precipitation Assessment Program (NAPAP). NAPAP looked at the entire problem from a scientific perspective. It enlarged a network of monitoring sites to determine how acidic the precipitation actually was, and to determine long-term trends, and established a network for dry deposition. It looked at the effects of acid rain and funded research on the effects of acid precipitation on freshwater and terrestrial ecosystems, historical buildings, monuments, and building materials. It also funded extensive studies on atmospheric processes and potential control programs.

From the start, policy advocates from all sides attempted to influence NAPAP activities to support their particular policy advocacy efforts, or to disparage those of their opponents.[20] For the US Government's scientific enterprise, a significant impact of NAPAP were lessons learned in the assessment process and in environmental research management to a relatively large group of scientists, program managers and the public.[21]

In 1981, the National Academy of Sciences was looking into research about the controversial issues regarding acid rain.[22] President Ronald Reagan did not place a huge attention on the issues of acid rain[23] until his personal visit to Canada and confirmed that Canadian border suffered from the drifting pollution from smokestacks in Midwest of US. Reagan honored the agreement to Canadian Prime Minister Pierre Trudeau’s enforcement of anti-pollution regulation.[24] In 1982, US President Ronald Reagan commissioned William Nierenberg to serve on the National Science Board.[25] Nierenberg selected scientists including Gene Likens to serve on a panel to draft a report on acid rain. In 1983, the panel of scientists came up with a draft report, which concluded that acid rain is a real problem and solutions should be sought.[26] White House Office of Science and Technology Policy reviewed the draft report and sent Fred Singer’s suggestions of the report, which cast doubt on the cause of acid rain.[27] The panelists revealed rejections against Singer’s positions and submitted the report to Nierenberg in April. In May 1983, the House of Representatives voted against legislation that aimed to control sulfur emissions. There was a debate about whether Nierenberg delayed to release the report. Nierenberg himself denied the saying about his suppression of the report and explained that the withheld of the report after the House's vote was due to the fact that the report was not ready to be published.[28]

In 1991, the US National Acid Precipitation Assessment Program (NAPAP) provided its first assessment of acid rain in the United States.[29] It reported that 5% of New England Lakes were acidic, with sulfates being the most common problem. They noted that 2% of the lakes could no longer support Brook Trout, and 6% of the lakes were unsuitable for the survival of many species of minnow. Subsequent Reports to Congress have documented chemical changes in soil and freshwater ecosystems, nitrogen saturation, decreases in amounts of nutrients in soil, episodic acidification, regional haze, and damage to historical monuments.

Meanwhile, in 1990, the US Congress passed a series of amendments to the Clean Air Act.[30] Title IV of these amendments established the a cap and trade system designed to control emissions of sulfur dioxide and nitrogen oxides.[31] Title IV called for a total reduction of about 10 million tons of SO2 emissions from power plants, close to a 50% reduction.[31] It was implemented in two phases. Phase I began in 1995, and limited sulfur dioxide emissions from 110 of the largest power plants to a combined total of 8.7 million tons of sulfur dioxide. One power plant in New England (Merrimack) was in Phase I. Four other plants (Newington, Mount Tom, Brayton Point, and Salem Harbor) were added under other provisions of the program. Phase II began in 2000, and affects most of the power plants in the country.

During the 1990s, research continued. On March 10, 2005, the EPA issued the Clean Air Interstate Rule (CAIR). This rule provides states with a solution to the problem of power plant pollution that drifts from one state to another. CAIR will permanently cap emissions of SO2 and NOx in the eastern United States. When fully implemented, CAIR will reduce SO2 emissions in 28 eastern states and the District of Columbia by over 70% and NOx emissions by over 60% from 2003 levels.[32]

Overall, the program's cap and trade program has been successful in achieving its goals. Since the 1990s, SO2 emissions have dropped 40%, and according to the Pacific Research Institute, acid rain levels have dropped 65% since 1976.[33][34] Conventional regulation was used in the European Union, which saw a decrease of over 70% in SO2 emissions during the same time period.[35]

In 2007, total SO2 emissions were 8.9 million tons, achieving the program's long-term goal ahead of the 2010 statutory deadline.[36]

In 2007 the EPA estimated that by 2010, the overall costs of complying with the program for businesses and consumers would be $1 billion to $2 billion a year, only one fourth of what was originally predicted.[33] Forbes says: In 2010, by which time the cap and trade system had been augmented by the George W. Bush administration's Clean Air Interstate Rule, SO2 emissions had fallen to 5.1 million tons.[37]

The term citizen science can be traced back as far as January 1989 and a campaign by the Audubon Society to measure acid rain. Scientist Muki Haklay cites in a policy report for the Wilson Center entitled 'Citizen Science and Policy: A European Perspective' a first use of the term 'citizen science' by R. Kerson in the magazine MIT Technology Review from January 1989.[38][39] Quoting from the Wilson Center report: "The new form of engagement in science received the name "citizen science". The first recorded example of the use of the term is from 1989, describing how 225 volunteers across the US collected rain samples to assist the Audubon Society in an acid-rain awareness raising campaign. The volunteers collected samples, checked for acidity, and reported back to the organization. The information was then used to demonstrate the full extent of the phenomenon."[38][39]

Emissions of chemicals leading to acidification

The most important gas which leads to acidification is sulfur dioxide. Emissions of nitrogen oxides which are oxidized to form nitric acid are of increasing importance due to stricter controls on emissions of sulfur compounds. 70 Tg(S) per year in the form of SO2 comes from fossil fuel combustion and industry, 2.8 Tg(S) from wildfires and 7–8 Tg(S) per year from volcanoes.[40]

Natural phenomena

The principal natural phenomena that contribute acid-producing gases to the atmosphere are emissions from volcanoes. Thus, for example, fumaroles from the Laguna Caliente crater of Poás Volcano create extremely high amounts of acid rain and fog, with acidity as high as a pH of 2, clearing an area of any vegetation and frequently causing irritation to the eyes and lungs of inhabitants in nearby settlements. Acid-producing gasses are also created by biological processes that occur on the land, in wetlands, and in the oceans. The major biological source of sulfur compounds is dimethyl sulfide.

Nitric acid in rainwater is an important source of fixed nitrogen for plant life, and is also produced by electrical activity in the atmosphere such as lightning.[41]

Acidic deposits have been detected in glacial ice thousands of years old in remote parts of the globe.[14]

Soils of coniferous forests are naturally very acidic due to the shedding of needles, and the results of this phenomenon should not be confused with acid rain.

Human activity

The principal cause of acid rain is sulfur and nitrogen compounds from human sources, such as electricity generation, factories, and motor vehicles. Electrical power generation using coal is among the greatest contributors to gaseous pollution responsible for acidic rain. The gases can be carried hundreds of kilometers in the atmosphere before they are converted to acids and deposited. In the past, factories had short funnels to let out smoke but this caused many problems locally; thus, factories now have taller smoke funnels. However, dispersal from these taller stacks causes pollutants to be carried farther, causing widespread ecological damage.

Chemical processes

Combustion of fuels produces sulfur dioxide and nitric oxides. They are converted into sulfuric acid and nitric acid.[42]

Gas phase chemistry

In the gas phase sulfur dioxide is oxidized by reaction with the hydroxyl radical via an intermolecular reaction:[5]

SO2 + OH· → HOSO2·

which is followed by:

HOSO2· + O2 → HO2· + SO3

In the presence of water, sulfur trioxide (SO3) is converted rapidly to sulfuric acid:

SO3 (g) + H2O (l) → H2SO4 (aq)

Nitrogen dioxide reacts with OH to form nitric acid:

Air Pollution-Causes&Effects
This shows the process of the air pollution being released into the atmosphere and the areas that will be affected.
NO2 + OH· → HNO3

Chemistry in cloud droplets

When clouds are present, the loss rate of SO2 is faster than can be explained by gas phase chemistry alone. This is due to reactions in the liquid water droplets.


Sulfur dioxide dissolves in water and then, like carbon dioxide, hydrolyses in a series of equilibrium reactions:

SO2 (g) + H2O ⇌ SO2·H2O
SO2·H2O ⇌ H+ + HSO3
HSO3 ⇌ H+ + SO32−

There are a large number of aqueous reactions that oxidize sulfur from S(IV) to S(VI), leading to the formation of sulfuric acid. The most important oxidation reactions are with ozone, hydrogen peroxide and oxygen (reactions with oxygen are catalyzed by iron and manganese in the cloud droplets).[5]

Acid deposition

Wet deposition

Wet deposition of acids occurs when any form of precipitation (rain, snow, and so on.) removes acids from the atmosphere and delivers it to the Earth's surface. This can result from the deposition of acids produced in the raindrops (see aqueous phase chemistry above) or by the precipitation removing the acids either in clouds or below clouds. Wet removal of both gases and aerosols are both of importance for wet deposition.

Dry deposition

Acid deposition also occurs via dry deposition in the absence of precipitation. This can be responsible for as much as 20 to 60% of total acid deposition.[43] This occurs when particles and gases stick to the ground, plants or other surfaces.

Adverse effects

Acid rain has been shown to have adverse impacts on forests, freshwaters and soils, killing insect and aquatic life-forms as well as causing damage to buildings and having impacts on human health.

Surface waters and aquatic animals

Not all fish, shellfish, or the insects that they eat can tolerate the same amount of acid; for example, frogs can tolerate water that is more acidic (i.e., has a lower pH) than trout.

Both the lower pH and higher aluminium concentrations in surface water that occur as a result of acid rain can cause damage to fish and other aquatic animals. At pH lower than 5 most fish eggs will not hatch and lower pH can kill adult fish. As lakes and rivers become more acidic biodiversity is reduced. Acid rain has eliminated insect life and some fish species, including the brook trout in some lakes, streams, and creeks in geographically sensitive areas, such as the Adirondack Mountains of the United States.[44] However, the extent to which acid rain contributes directly or indirectly via runoff from the catchment to lake and river acidity (i.e., depending on characteristics of the surrounding watershed) is variable. The United States Environmental Protection Agency's (EPA) website states: "Of the lakes and streams surveyed, acid rain caused acidity in 75% of the acidic lakes and about 50% of the acidic streams".[44] Lakes hosted by silicate basement rocks are more acidic than lakes within limestone or other basement rocks with a carbonate composition (i.e. marble) due to buffering effects by carbonate minerals, even with the same amount of acid rain.[45]


Soil biology and chemistry can be seriously damaged by acid rain. Some microbes are unable to tolerate changes to low pH and are killed.[46] The enzymes of these microbes are denatured (changed in shape so they no longer function) by the acid. The hydronium ions of acid rain also mobilize toxins, such as aluminium, and leach away essential nutrients and minerals such as magnesium.[47]

2 H+ (aq) + Mg2+ (clay) ⇌ 2 H+ (clay) + Mg2+ (aq)

Soil chemistry can be dramatically changed when base cations, such as calcium and magnesium, are leached by acid rain thereby affecting sensitive species, such as sugar maple (Acer saccharum).[48][49]

Forests and other vegetation

Acid rain woods1
Acid rain can have severe effects on vegetation. A forest in the Black Triangle in Europe.

Adverse effects may be indirectly related to acid rain, like the acid's effects on soil (see above) or high concentration of gaseous precursors to acid rain. High altitude forests are especially vulnerable as they are often surrounded by clouds and fog which are more acidic than rain.

Other plants can also be damaged by acid rain, but the effect on food crops is minimized by the application of lime and fertilizers to replace lost nutrients. In cultivated areas, limestone may also be added to increase the ability of the soil to keep the pH stable, but this tactic is largely unusable in the case of wilderness lands. When calcium is leached from the needles of red spruce, these trees become less cold tolerant and exhibit winter injury and even death.[50][51]

Ocean acidification

Acid rain has a much less harmful effect on the oceans. Acid rain can cause the ocean's pH to fall, making it more difficult for different coastal species to create their exoskeletons that they need to survive. These coastal species link together as part of the ocean's food chain and without them being a source for other marine life to feed off of more marine life will die.[52]

Coral's limestone skeletal is sensitive to pH drop, because the calcium carbonate, core component of the limestone dissolves in acidic (low pH) solutions.

Human health effects

Acid rain does not directly affect human health. The acid in the rainwater is too dilute to have direct adverse effects. The particulates responsible for acid rain (sulfur dioxide and nitrogen oxides) do have an adverse effect. Increased amounts of fine particulate matter in the air contribute to heart and lung problems including asthma and bronchitis.[53]

Other adverse effects

Pollution - Damaged by acid rain
Effect of acid rain on statues
Skulptur aus Sandstein, Dresden 2012-09-06-0555
Acid rain and weathering

Acid rain can damage buildings, historic monuments, and statues, especially those made of rocks, such as limestone and marble, that contain large amounts of calcium carbonate. Acids in the rain react with the calcium compounds in the stones to create gypsum, which then flakes off.

CaCO3 (s) + H2SO4 (aq) ⇌ CaSO4 (s) + CO2 (g) + H2O (l)

The effects of this are commonly seen on old gravestones, where acid rain can cause the inscriptions to become completely illegible. Acid rain also increases the corrosion rate of metals, in particular iron, steel, copper and bronze.[54][55]

Affected areas

Places significantly impacted by acid rain around the globe include most of eastern Europe from Poland northward into Scandinavia,[56] the eastern third of the United States,[57] and southeastern Canada. Other affected areas include the southeastern coast of China and Taiwan.[58]

Prevention methods

Technical solutions

Many coal-firing power stations use flue-gas desulfurization (FGD) to remove sulfur-containing gases from their stack gases. For a typical coal-fired power station, FGD will remove 95% or more of the SO2 in the flue gases. An example of FGD is the wet scrubber which is commonly used. A wet scrubber is basically a reaction tower equipped with a fan that extracts hot smoke stack gases from a power plant into the tower. Lime or limestone in slurry form is also injected into the tower to mix with the stack gases and combine with the sulfur dioxide present. The calcium carbonate of the limestone produces pH-neutral calcium sulfate that is physically removed from the scrubber. That is, the scrubber turns sulfur pollution into industrial sulfates.

In some areas the sulfates are sold to chemical companies as gypsum when the purity of calcium sulfate is high. In others, they are placed in landfill. The effects of acid rain can last for generations, as the effects of pH level change can stimulate the continued leaching of undesirable chemicals into otherwise pristine water sources, killing off vulnerable insect and fish species and blocking efforts to restore native life.

Fluidized bed combustion also reduces the amount of sulfur emitted by power production.

Vehicle emissions control reduces emissions of nitrogen oxides from motor vehicles.

International treaties

International treaties on the long-range transport of atmospheric pollutants have been agreed for example, the 1985 Helsinki Protocol on the Reduction of Sulphur Emissions under the Convention on Long-Range Transboundary Air Pollution. Canada and the US signed the Air Quality Agreement in 1991. Most European countries and Canada have signed the treaties.

Emissions trading

In this regulatory scheme, every current polluting facility is given or may purchase on an open market an emissions allowance for each unit of a designated pollutant it emits. Operators can then install pollution control equipment, and sell portions of their emissions allowances they no longer need for their own operations, thereby recovering some of the capital cost of their investment in such equipment. The intention is to give operators economic incentives to install pollution controls.

The first emissions trading market was established in the United States by enactment of the Clean Air Act Amendments of 1990.[59] The overall goal of the Acid Rain Program established by the Act[60] is to achieve significant environmental and public health benefits through reductions in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx), the primary causes of acid rain. To achieve this goal at the lowest cost to society, the program employs both regulatory and market based approaches for controlling air pollution.

See also


  1. ^ Likens, Gene E.; Keene, William C.; Miller, John M.; Galloway, James N. (1987). "Chemistry of precipitation from a remote, terrestrial site in Australia". Journal of Geophysical Research. 92 (D11): 13299. Bibcode:1987JGR....9213299L. doi:10.1029/JD092iD11p13299.
  2. ^ E. S. de Beer, ed. The Diary of John Evelyn, III, 1955 (September 19, 1667) p. 495.
  3. ^ a b Glossary, United States: NASA Earth Observatory, acid rain, archived from the original on December 13, 2011, retrieved February 15, 2013
  4. ^ Weathers, K. C. and Likens, G. E. (2006). "Acid rain", pp. 1549–1561 in: W. N. Rom and S. Markowitz (eds.). Environmental and Occupational Medicine. Lippincott-Raven Publ., Philadelphia. Fourth Edition, ISBN 0-7817-6299-5.
  5. ^ a b c Seinfeld, John H.; Pandis, Spyros N (1998). Atmospheric Chemistry and Physics — From Air Pollution to Climate Change. John Wiley and Sons, Inc. ISBN 978-0-471-17816-3
  6. ^ Likens, G. E.; Bormann, F. H.; Johnson, N. M. (1972). "Acid rain". Environment. 14 (2): 33–40. doi:10.1080/00139157.1972.9933001.
  7. ^ Acid Rain in New England, A Brief History Archived September 25, 2010, at the Wayback Machine. Retrieved on February 9, 2013.
  8. ^ Brøgger, Waldemar Christofer (1881). "Note on a contaminated snowfall under the heading Mindre meddelelser (Short communications)". Naturen. 5: 47.
  9. ^ Likens, G. E.; Bormann, F. H. (1974). "Acid Rain: A Serious Regional Environmental Problem". Science. 184 (4142): 1176–9. Bibcode:1974Sci...184.1176L. doi:10.1126/science.184.4142.1176. PMID 17756304.
  10. ^ Keller, C. K.; White, T. M.; O'Brien, R.; Smith, J. L. (2006). "Soil CO2 dynamics and fluxes as affected by tree harvest in an experimental sand ecosystem". Journal of Geophysical Research. 111 (G3): G03011. Bibcode:2006JGRG..111.3011K. doi:10.1029/2005JG000157.
  11. ^ Galloway, JN; Dianwu, Z; Jiling, X; Likens, GE (1987). "Acid rain: China, United States, and a remote area". Science. 236 (4808): 1559–62. Bibcode:1987Sci...236.1559G. doi:10.1126/science.236.4808.1559. PMID 17835740.
  12. ^ Chandru (September 9, 2006). "CHINA: Industrialization pollutes its country side with Acid Rain". Archived from the original on June 20, 2010. Retrieved November 18, 2010.
  13. ^ Lefohn, A.S.; Husar, J.D.; Husar, R.B. (1999), Global Sulfur Emissions Database, United States: A.S.L. & Associates
  14. ^ a b Likens, G. E.; Wright, R. F.; Galloway, J. N.; Butler, T. J. (1979). "Acid rain". Scientific American. 241 (4): 43–51. Bibcode:1979SciAm.241d..43L. doi:10.1038/scientificamerican1079-43.
  15. ^ Likens, G. E. (1984). "Acid rain: the smokestack is the "smoking gun"". Garden. 8 (4): 12–18.
  16. ^ "Art Under Wraps", Harvard Magazine, March–April 2000
  17. ^ Likens, Gene E.; Bormann, F. Herbert; Johnson, Noye M. (1972). "Acid Rain". Environment: Science and Policy for Sustainable Development. 14 (2): 33–40. doi:10.1080/00139157.1972.9933001.
  18. ^ Johnson, Noye M.; Driscoll, Charles T.; Eaton, John S.; Likens, Gene E.; McDowell, William H. (September 1, 1981). "'Acid rain', dissolved aluminum and chemical weathering at the Hubbard Brook Experimental Forest, New Hampshire". Geochimica et Cosmochimica Acta. 45 (9): 1421–1437. Bibcode:1981GeCoA..45.1421J. doi:10.1016/0016-7037(81)90276-3.
  19. ^ Hall, Ronald J.; Likens, Gene E.; Fiance, Sandy B.; Hendrey, George R. (August 1, 1980). "Experimental Acidification of a Stream in the Hubbard Brook Experimental Forest, New Hampshire". Ecology. 61 (4): 976–989. doi:10.2307/1936765. ISSN 1939-9170. JSTOR 1936765.
  20. ^ a b Lackey, R.T. (1997). "Science, policy, and acid rain: lessons learned" (PDF). Renewable Resources Journal. 15 (1): 9–13.
  21. ^ Winstanley, Derek; Lackey, Robert T.; Warnick, Walter L.; Malanchuk, John (1998). "Acid rain: Science and policy making". Environmental Science & Policy. 1: 51. doi:10.1016/S1462-9011(98)00006-9.
  22. ^ Times, Robert Reinhold, Special To The New York (June 8, 1982). "ACID RAIN ISSUE CREATES STRESS BETWEEN ADMINISTRATION AND SCIENCE ACADEMY". The New York Times. ISSN 0362-4331. Retrieved November 16, 2016.
  23. ^ "Ronald Reagan on Environment". Retrieved November 16, 2016.
  24. ^ "HYSTERIA ABOUT ACID RAIN Even Ronald Reagan now casts it as the villain. He is overriding a lot of scientific evidence. - April 14, 1986". Retrieved November 16, 2016.
  25. ^ "Ronald Reagan: Nomination of William A. Nierenberg To Be a Member of the National Science Board". Retrieved November 16, 2016.
  26. ^ "Report of the Acid Rain Peer Review Panel". Document Display | NEPIS | US EPA. July 1984. Retrieved November 16, 2016.
  27. ^ "From tobacco to climate change, 'merchants of doubt' undermined the science". Grist. April 17, 2010. Retrieved November 16, 2016.
  28. ^ Franklin, Ben A. (August 18, 1984). "LEGISLATORS SAT WHITE HOUSE SUPPRESSED ACID RAIN REPORT". The New York Times. ISSN 0362-4331. Retrieved November 16, 2016.
  29. ^ The US National Acid Precipitation Assessment Program : 1990 integrated assessment report. Washington, D.C. : National Acid Precipitation Assessment Program, Office of the Director, [1991]
  30. ^ "Clean Air Act Title IV - Subchapter A: Acid Deposition Control | Overview of the Clean Air Act and Air Pollution | US EPA". June 3, 2015. Retrieved March 20, 2018.
  31. ^ a b John Bachmann, David Calkins, Margo Oge. “Cleaning the Air We Breathe: A Half Century of Progress.” EPA Alumni Association. September 2017. Pages 26-27.
  32. ^ "US EPA: A Brief History of Acid Rain". United States Environmental Protection Agency. 2002. Archived from the original on September 25, 2010. Retrieved November 18, 2010.
  33. ^ a b 'Cap-and-trade' model eyed for cutting greenhouse gases, San Francisco Chronicle, December 3, 2007.
  34. ^ "Facts On File News Services Databases". Retrieved November 18, 2010.
  35. ^ Gilberston, T. and Reyes, O. 2009. Carbon Trading: how it works and why it fails. Dag Hammarskjöld Foundation: 22
  36. ^ Acid Rain Program 2007 Progress Report, United States Environmental Protection Agency, January 2009.
  37. ^ Gerdes, Justin. "Cap and Trade Curbed Acid Rain: 7 Reasons Why It Can Do The Same For Climate Change". Forbes. Forbes. Retrieved October 27, 2014.
  38. ^ a b Muki Haklay (2015). "Citizen Science and Policy: A European Perspective" (PDF). Woodrow Wilson International Center for Scholars. p. 11. Retrieved June 3, 2016.
  39. ^ a b R. Kerson (1989). "Lab for the Environment". MIT Technology Review. Vol. 92 no. 1. pp. 11–12.
  40. ^ Berresheim, H.; Wine, P.H. and Davies D.D. (1995). "Sulfur in the Atmosphere". In Composition, Chemistry and Climate of the Atmosphere, ed. H.B. Singh. Van Nostrand Rheingold ISBN 0-442-01264-0
  41. ^ . January 24, 2018 Retrieved January 24, 2018. Missing or empty |title= (help)
  42. ^ Clean Air Act Reduces Acid Rain In Eastern United States, ScienceDaily, September 28, 1998
  43. ^ "UK National Air Quality Archive: Air Pollution Glossary". April 1, 2002. Archived from the original on April 17, 2009. Retrieved November 18, 2010.
  44. ^ a b US EPA: Effects of Acid Rain – Surface Waters and Aquatic Animals
  45. ^ Kesler, Stephen (2015). Mineral Resources, Economics and the Environment. Cambridge University. ISBN 9781107074910.
  46. ^ Rodhe, H., et al. The global distribution of acidifying wet deposition. Environmental Science and TEchnology. vlo. 36, no. 20 (October) p. 4382–8
  47. ^ US EPA: Effects of Acid Rain – Forests Archived July 26, 2008, at the Wayback Machine
  48. ^ Likens, G.E.; Driscoll, C.T.; Buso, D.C.; Mitchell, M.J.; Lovett, G.M.; Bailey, S.W.; Siccama, T.G.; Reiners, W.A.; Alewell, C. (2002). "The biogeochemistry of sulfur at Hubbard Brook" (PDF). Biogeochemistry. 60 (3): 235. doi:10.1023/A:1020972100496.
  49. ^ Likens, G. E.; Driscoll, C. T.; Buso, D. C. (1996). "Long-Term Effects of Acid Rain: Response and Recovery of a Forest Ecosystem" (PDF). Science. 272 (5259): 244. Bibcode:1996Sci...272..244L. doi:10.1126/science.272.5259.244.
  50. ^ DeHayes, D.H., Schaberg, P.G. and G.R. Strimbeck. (2001). Red Spruce Hardiness and Freezing Injury Susceptibility. In: F. Bigras, ed. Conifer Cold Hardiness. Kluwer Academic Publishers, the Netherlands ISBN 0-7923-6636-0.
  51. ^ Lazarus, Brynne E.; Schaberg, Paul G.; Hawley, Gary J.; DeHayes, Donald H. (2006). "Landscape-scale spatial patterns of winter injury to red spruce foliage in a year of heavy region-wide injury" (PDF). Can. J. For. Res. 36: 142–152. doi:10.1139/x05-236. highbeam copy
  52. ^ "Acid Rain Has Disproportionate Impact on Near-Shore Ocean Waters - Windows to the Universe".
  53. ^ Effects of Acid Rain – Human Health. (June 2, 2006). Retrieved on 2013-02-09.
  54. ^ Reisener, A.; Stäckle, B.; Snethlage, R. (1995). "ICP on effects on materials". Water, Air, & Soil Pollution. 85 (4): 2701–2706. Bibcode:1995WASP...85.2701R. doi:10.1007/BF01186242. Retrieved November 18, 2010.
  55. ^ "Approaches in modeling the impact of air pollution-induced material degradation" (PDF). Archived from the original (PDF) on July 16, 2011. Retrieved November 18, 2010.
  56. ^ Ed. Hatier (1993). "Acid Rain in Europe". United Nations Environment Programme GRID Arendal. Archived from the original on August 22, 2009. Retrieved January 31, 2010.
  57. ^ US Environmental Protection Agency (2008). "Clean Air Markets 2008 Highlights". Retrieved January 31, 2010.
  58. ^ "Acid Rain - Green Education Foundation | GEF | Sustainability Education". Retrieved November 2, 2017.
  59. ^ Former Deputy Administrator Hank Habicht talks about management at EPA. An Interview with Hank Habicht Video, Transcript (see p6). December 21, 2012.
  60. ^ Clean Air Act Amendments of 1990, 42 U.S. Code 7651

External links

Academy Comics

Academy Comics was an American comic book publisher founded by Mark Paniccia (an editor at Marvel Comics as of 2011). It was founded as Pyramid Publishing in 1986, and became New Century Comics by 1990, which served primarily as a vehicle to publish Paniccia's own sword and sorcery comics. It later changed its name to Acid Rain Studios in order to publish a series of vampire and gothic comic books. The name was changed to Academy after it acquired the Robotech license in 1994. Its last title was Noble A.R.M.O.U.R. Halberder by the Waltrip brothers after the license ended in 1996.

Acid Rain (Alexis Jordan song)

"Acid Rain" is a song recorded by American recording artist Alexis Jordan, taken from her upcoming second studio album (2014). It was written by Sia Furler with co-writing and production from Norwegian production outfit StarGate and Dutch disc jockeys (DJs) Bingo Players. The latter duo are credited for the inclusion of a sample of their own electro house single "Get Up (Rattle)". "Acid Rain" initially premiered on January 14, 2013, featuring two verses of Jordan's label-mate, American rapper J. Cole. An alternate version of the song excluding Cole was released for digital download on February 20, 2013.

Acid Rain (album)

Acid Rain is the third compilation album by Esham. Released in 2002, it is the first of three albums by the rapper released on Psychopathic Records, followed by the studio albums Repentance and A-1 Yola. It is known as the "Esham Story".

Acid Rain Program

The Acid Rain Program is a market-based initiative taken by the United States Environmental Protection Agency in an effort to reduce overall atmospheric levels of sulfur dioxide and nitrogen oxides, which cause acid rain. The program is an implementation of emissions trading that primarily targets coal-burning power plants, allowing them to buy and sell emission permits (called "allowances") according to individual needs and costs. In 2011, the trading program that existed since 1995 was supplemented by four separate trading programs under the Cross-State Air Pollution Rule (CSAPR). On August 21, 2012, the United States Court of Appeals for the District of Columbia issued its Opinion and Order in the appeal of the Cross State Air Pollution Rule (CSAPR) for two independent legal reasons. The stay on CSAPR was lifted in October 2014, allowing implementation of the law and its trading programs to begin.A 2017 NBER paper found that the "Acid Rain Program caused lasting improvements in ambient air quality," reducing mortality risk by 5% over 10 years.

Acid Rap

Acid Rap is the second mixtape by American rapper Chance the Rapper. It was released on April 30, 2013, as a free digital download. In July 2013, the album debuted at number 63 on the Billboard Top R&B/Hip-Hop Albums, due to bootleg downloads on iTunes and Amazon not affiliated with the artist. The mixtape has been certified "diamond" on mixtape site Datpiff, for garnering over 10,000,000 downloads.

Environmental impact of the petroleum industry

Petroleum is one of the main sources of energy in the World. Petroleum and its by-products are used to fuel various forms of transportation, industry and domestic electricity use. Petroleum is also used to manufacture plastics which provides products essential for daily life. Also, petroleum has helped create many products like cosmetics, tyres (rubber) pesticides etc. Over the years there have been increased concerns over the environmental effects of the petroleum industry. The environmental impacts of petroleum are mainly negative. This is due to the toxicity of petroleum which contributes to air pollution, acid rain, and various illnesses in humans. Petroleum also fuels climate change, due to the increased greenhouse gas emissions in its extraction, refinement, transport and consumption phases.

Environmental issues in Greece

This page covers environmental issues in Greece.

Environmental soil science

Environmental soil science is the study of the interaction of humans with the pedosphere as well as critical aspects of the biosphere, the lithosphere, the hydrosphere, and the atmosphere. Environmental soil science addresses both the fundamental and applied aspects of the field including: buffers and surface water quality, vadose zone functions, septic drain field site assessment and function, land treatment of wastewater, stormwater, erosion control, soil contamination with metals and pesticides, remediation of contaminated soils, restoration of wetlands, soil degradation, nutrient management, movement of viruses and bacteria in soils and waters, bioremediation, application of molecular biology and genetic engineering to development of soil microbes that can degrade hazardous pollutants, land use, global warming, acid rain, and the study of anthropogenic soils, such as terra preta. Much of the research done in environmental soil science is produced through the use of models.

Fall on Me

"Fall on Me" is a song by the American alternative rock band R.E.M. from their fourth album Lifes Rich Pageant (1986). It was the first of two singles released from that LP. It peaked at number 94 on the Billboard Hot 100. The song was one of the band's early compositions about environmentalism, discussing acid rain. It also transitioned from their murky lyrics and jangling guitar of their first three albums to a more accessible sound influenced by producer Don Gehman.

Gene Likens

Gene Elden Likens (born January 6, 1935) is an American limnologist and ecologist. He co-founded the Hubbard Brook Ecosystem Study at the Hubbard Brook Experimental Forest in 1963, and founded the Cary Institute of Ecosystem Studies in Millbrook, New York in 1983.A leading pioneer in long-term multidisciplinary ecological studies, Likens examines energy flow and biogeochemical flux models in the ecosystems of forests, streams and lakes. Likens is best known for leading the team of scientists that discovered acid rain in North America, and connected fossil fuels with increasing acidity of precipitation. In addition to its scientific impact, this work has influenced public debate and governmental policy, particularly the United States Congress's Clean Air Act Amendments of 1990.


Hydrobiology is the science of life and life processes in water. Much of modern hydrobiology can be viewed as a sub-discipline of ecology but the sphere of hydrobiology includes taxonomy, economic biology, industrial biology, morphology, physiology etc. The one distinguishing aspect is that all relate to aquatic organisms. Much work is closely related to limnology and can be divided into lotic system ecology (flowing waters) and lentic system ecology (still waters).

One of the significant areas of current research is eutrophication. Special attention is paid to biotic interactions in plankton assemblage including the microbial loop, the mechanism of influencing water blooms, phosphorus load and lake turnover. Another subject of research is the acidification of mountain lakes. Long-term studies are carried out on changes in the ionic composition of the water of rivers, lakes and reservoirs in connection with acid rain and fertilisation. One goal of current research is elucidation of the basic environmental functions of the ecosystem in reservoirs, which are important for water quality management and water supply.

Much of the early work of hydrobiologists concentrated on the biological processes utilised in sewage treatment and water purification especially slow sand filters. Other historically important work sought to provide biotic indices for classifying waters according to the biotic communities that they supported. This work continues to this day in Europe in the development of classification tools for assessing water bodies for the EU water framework directive.

Joyce Elaine Roop

Joyce Elaine Roop (1952–1995) was an attorney and environmental activist.

Born in Chicago, Roop attended the University of California at Santa Barbara, where she helped found the Isla Vista Recreation and Park District and was then elected to the initial board of directors. In 1976 she moved from Isla Vista to Massachusetts, where she studied at Northeastern University School of Law.

While a high school student in 1967, Roop joined a nationally publicized protest and marched from California's border with Oregon down the length of the state to a defense plant near Los Angeles to protest the US war in Vietnam.

After law school, Roop worked for Ralph Nader's Public Citizen Congress Watch organization and the Massachusetts Public Interest Research Group, where she spearheaded litigation to stop acid rain from coal fired power plants.

Kryptonite (album)

Kryptonite is the second studio album by British-based DJ and record producer DJ Fresh. The album primarily features drum and bass tracks, featuring drum and bass group Sigma and vocalists Stamina MC, Koko, Valkyrie and Ce'cile. The album has been pushed back various times, each time with a new track or an old track removed. Tracks removed from Kryptonite are "Spaceface", a drum and bass tune removed due to Fresh losing parts of the song itself, Fresh has confirmed that he doesn't know "what's going on" with "Lazer Squad", "Off World" was put onto a 12" with "Direct Order" by The Funktion, "Cylon" became the flip to "Lassitude", and "X-Project" (VIP mix) has been removed for an unknown reason. There was a mispress of the talkbox promo vinyl which had "Acid Rain" on the flipside rather than the intended song, "Fight". Due to the public reception to the preference over "Acid Rain" than to "Fight", it ("Acid Rain") was made the official flipside rather than "Fight".

A minimix was released on 9 June, which can be found on Fresh's Myspace.


Multi-Love is the third studio album from the band Unknown Mortal Orchestra. It was released on 26 May 2015. The track "Can't Keep Checking My Phone" was featured by EA Sports on FIFA 16.

The title Multi-Love is a reference to the polyamorous relationship frontman Ruban Nielson had with his wife and a younger woman from Tokyo, Japan for a year, before her visa expired and the relationship ended. The topic is a prevalent theme in the album's lyrics.


In atmospheric chemistry, NO x is a generic term for the nitrogen oxides that are most relevant for air pollution, namely nitric oxide (NO) and nitrogen dioxide (NO 2 ). These gases contribute to the formation of smog and acid rain, as well as affecting tropospheric ozone.

NO x gases are usually produced from the reaction among nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as occur in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution. NO x gases are also produced naturally by lightning.

The term NO x is chemistry shorthand for molecules containing one nitrogen and one or more oxygen atom. It is generally meant to include nitrous oxide (N2O), although nitrous oxide is a fairly inert oxide of nitrogen that has many uses as an oxidizer for rockets and car engines, an anesthetic, and a propellant for aerosol sprays and whipped cream. Nitrous oxide plays hardly any role in air pollution, although it may have a significant impact on the ozone layer, and is a significant greenhouse gas.

NO y is defined as the sum of NO x plus the NO z compounds produced from the oxidation of NO x which include nitric acid, nitrous acid(HONO), dinitrogen pentoxide(N2O5), peroxyacetyl nitrate(PAN), alkyl nitrates (RONO2), peroxyalkyl nitrates (ROONO2), the nitrate radical (NO3), and peroxynitric acid(HNO4).

Phoenix Copper Smelter

The Cuprom Phoenix Copper Smelter is a smelter of sulfurous copper ores in Baia Mare, Romania.

Due to the toxic fumes causing acid rain, it has a 351.5 m (1,153 ft) chimney, built in 1995, making it the tallest artificial structure in Romania and the third tallest chimney in Europe.

The tower is no longer in use.

Rebirth (Angra album)

Rebirth is the fourth album by the Brazilian progressive metal band Angra, the first since a major restructuring of the band's line-up.

Soil acidification

Soil acidification is the buildup of hydrogen cations, which reduces the soil pH. Chemically, this happens when a proton donor gets added to the soil. The donor can be an acid, such as nitric acid, sulfuric acid, or carbonic acid. It can also be a compound such as aluminium sulfate, which reacts in the soil to release protons. Acidification also occurs when base cations such as calcium, magnesium, potassium and sodium are leached from the soil.

Soil acidification naturally occurs as lichens and algae begin to break down rock surfaces. Acids continue with this dissolution as soil develops. With time and weathering, soils become more acidic in natural ecosystems. Soil acidification rates can vary, and increase with certain factors such as acid rain, agriculture, and pollution.

U.S.–Canada Air Quality Agreement

The Air Quality Agreement is an environmental treaty between Canada and the United States. It was signed on 13 March 1991 by Canadian prime minister Brian Mulroney and American President George H. W. Bush and entered into force immediately. It was popularly referred to during its negotiations as the "Acid Rain Treaty", especially in Canada. Negotiations began in 1986 when Mulroney first discussed the issue with then-president Reagan. Mulroney repeatedly pressed the issue in public meetings with Reagan in 1987 and 1988

The Government of the United States of America and the Government of Canada, hereinafter referred to as "the Parties",

Convinced that transboundary air pollution can cause significant harm to natural resources of vital environmental, cultural and economic importance, and to human health in both countries;

Desiring that emissions of air pollutants from sources within their countries not result in significant transboundary air pollution;

Convinced that transboundary air pollution can effectively be reduced through cooperative or coordinated action providing for controlling emissions of air pollutants in both countries;

Recalling the efforts they have made to control air pollution and the improved air quality that has resulted from such efforts in both countries;

Intending to address air-related issues of a global nature, such as climate change and stratospheric ozone depletion, in other fora;

Reaffirming Principle 21 of the Stockholm Declaration, which provides that "States have, in accordance with the Charter of the United Nations and the principles of international law, the sovereign right to exploit their own resources pursuant to their own environmental policies, and the responsibility to ensure that activities within their jurisdiction or control do not cause damage to the environment of other States or of areas beyond the limits of national jurisdiction";

Noting their tradition of environmental cooperation as reflected in the Boundary Waters Treaty of 1909, the Trail Smelter Arbitration of 1941, the Great Lakes Water Quality Agreement of 1978, as amended, the Memorandum of Intent Concerning Transboundary Air Pollution of 1980, the 1986 Joint Report of the Special Envoys on Acid Rain, as well as the ECE Convention on Long-Range Transboundary Air Pollution of 1979;

Convinced that a healthy environment is essential to assure the well-being of present and future generations in Canada and the United States, as well as of the global community;

Have agreed as follows: ...

Air pollution
Water pollution
Soil contamination
Radioactive contamination
Other types of pollution
Inter-government treaties
Major organizations

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