‘Working on it.
Industrial emissions, particularly sulphur dioxide, SO2, increase the leaching of base cations (Ca++, Mg++ K+) in soils over what would occur in the absence of those emissions. The main source of the SO2 is the burning of fossil fuels.
In Canada and the US, those emissions increased continuously as fossil fuel consumption increased, until about 1970, then began to decline.
Data from Smith et al., XXXX
reductions in sulfur emissions USA and Canada
“Acid Rain: A Serious Environmental Problem.”
“Acid Rain: A Serious Environmental Problem.”
https://www.sciencehistory.org/distillations/podcast/whatever-happened-to-acid-rain
https://en.wikipedia.org/wiki/Acid_rain#History
https://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=124955
Acid Rain: Scourge of the Past or Trend of the Present?
Now, Hubbard Brook LTER scientists have discovered that a combination of today’s higher atmospheric carbon dioxide (CO2) level and its atmospheric fallout is altering the hydrology and water quality of forested watersheds–in much the same way as acid rain.
“It’s taken years for New England forests, lakes and streams to recover from the acidification caused by atmospheric pollution,” says Saran Twombly, NSF program director for long-term ecological research.
“It appears that these forests and streams are under threat again. Climate change will likely return them to an acidified state. The implications for these environments, and for humans depending on them, are severe.”
https://www.cbc.ca/archives/entry/acid-rain-losing-fish-in-the-maritimes
https://waves-vagues.dfo-mpo.gc.ca/Library/40615133.pdf
BACKGROUND
In July 1980 the Cabinet Committee on Economie Development
approved resources until March, 1984 for an expanded and
accelerated departmental program to deal with the threat of “acid
rain” to Canadian fisheries resources. As we approach completion
of the fourth year of the program, it is timely to report on the
general progress.
Acid rain in Canada has eliminated all fish from hundreds of
lakes in Ontario and eliminated at least ten runs of Atlantic
salmon in Nova Scotia and has the potential for serious impacts
in Newfoundland and Quebec.
Acid rain is caused from the short and long range transport
and of oxides of sulphur and nitrogen released
during the burning of fossil fuels in electric power generation,
industrial processes and Over half of Canada’s
acid rain originates in the United States.
The first casualties of acid rain are sensitive lakes and
rivers located in areas containing noncalcareous bedrock and thin
soils. Most of Eastern Canada fits this description (see
Figure 1) and therefore most freshwater systems and especially
fish are potentially susceptible to being affected by acid rain.
——————-
Opinion
‘SALMON’S MURDEROUS TROUBLE IS ACID RAIN’
Feb. 23, 1982
Canada experiences the same swift salmon decline. In Nova Scotia, 100-year records show the salmon catch holding steady until 1950; today the nine most acidic rivers have no salmon; in many of the rest the fish decrease. It takes 15 to 20 years from the first trouble signs to salmon extinction, Canadian authorities say. They identify half of Canada’s acid rain as made in U.S.A.
https://publications.gc.ca/Collection-R/LoPBdP/CIR/7937-e.htm
Parliamentary Research Branch
ACID RAIN
Prepared by:
Alan Nixon, Thomas Curran
Science and Technology Division
Revised 30 September 1998
Although it is no longer at the forefront of environmental issues, acidic precipitation, or acid rain as it is commonly called, remains a subject of concern to many Canadians. When the acidification of lakes was first described in Ontario in the early 1950s, the phenomenon was considered to be simply a local problem resulting from the lakes’ proximity to nickel smelting operations in and around Sudbury. Since then, however, scientists have documented the acidification and the demise of numerous additional lakes; acidification is now acknowledged to be widespread and a major environmental problem.
Acidic precipitation is derived principally from emissions of sulphur and nitrogen oxides which are released to the environment during the combustion of fossil fuels and the smelting of sulphide ores. As the pollutants are transported for hundreds, or perhaps thousands, of kilometres through the atmosphere, the oxides enter into a complex series of chemical reactions to form acids. Sulphuric and nitric acids are the most frequently found types.
Freshwater ecosystems are most vulnerable to the harmful effects of acidic precipitation but damage can be inflicted on man-made structures and artifacts as well. The effects of acidic precipitation on terrestrial ecosystems, including agricultural crops and forests, are still not well-defined although most authorities agree that a potential for damage exists.
Although acid rain is not believed to pose a direct risk to human health, there is evidence that the inhalation of acid aerosols can irritate the respiratory tract and aggravate respiratory ailments. The issue is made more complicated, however, by the fact that the effects of acidic pollutants may be difficult to separate from those of other atmospheric pollutants such as ground-level ozone. Human health may also be harmed indirectly by elevated levels of toxic metals in drinking water and food which can occur as a result of acid deposition.
BACKGROUND AND ANALYSIS
A. Historical Perspective
Acid rain is not a new phenomenon although public awareness of the problem is a more recent development. In the mid-seventeenth century, Evelyn (in 1661) and Gaunt (in 1662) noted the influence of industrial emissions on the health of plants and people and the transboundary exchange of pollutants between England and France. They suggested remedial measures including the placement of industry outside of towns and the use of taller chimneys to spread the “smoke” into “distant parts.” In 1872, Smith, in a pioneering publication entitled “Air and Rain: The Beginnings of a Chemical Climatology”, first used the term “acid rain” and described many of the concepts we now consider part of the acidic precipitation problem.
79-37E
ACID RAIN
Prepared by:
Alan Nixon, Thomas Curran
Science and Technology Division
Revised 30 September 1998
TABLE OF CONTENTS
ISSUE DEFINITION
BACKGROUND AND ANALYSIS
A. Historical Perspective
B. Formation of Acid Rain
C. Emissions of Acidic Pollutants in North America
D. Acid Deposition
E. Environmental Effects of Acid Rain
1. Aquatic Ecosystems
2. Terrestrial Ecosystems
3. Human Health
4. Man-Made Structures
F. Areas of Canada Susceptible to Acidic Precipitation
G. Acid Rain Controls
1. The Canadian Acid Rain Control Program
2. Ontario Hydro
3. The U.S. Acid Rain Program
4. Canada-U.S. Air Quality Agreement
5. Second International SO2 Protocol
PARLIAMENTARY ACTION
A. Sub-committee on Acid Rain
B. Clean Air Act
CHRONOLOGY
SELECTED REFERENCES
ACID RAIN*
ISSUE DEFINITION
Although it is no longer at the forefront of environmental issues, acidic precipitation, or acid rain as it is commonly called, remains a subject of concern to many Canadians. When the acidification of lakes was first described in Ontario in the early 1950s, the phenomenon was considered to be simply a local problem resulting from the lakes’ proximity to nickel smelting operations in and around Sudbury. Since then, however, scientists have documented the acidification and the demise of numerous additional lakes; acidification is now acknowledged to be widespread and a major environmental problem.
Acidic precipitation is derived principally from emissions of sulphur and nitrogen oxides which are released to the environment during the combustion of fossil fuels and the smelting of sulphide ores. As the pollutants are transported for hundreds, or perhaps thousands, of kilometres through the atmosphere, the oxides enter into a complex series of chemical reactions to form acids. Sulphuric and nitric acids are the most frequently found types.
Freshwater ecosystems are most vulnerable to the harmful effects of acidic precipitation but damage can be inflicted on man-made structures and artifacts as well. The effects of acidic precipitation on terrestrial ecosystems, including agricultural crops and forests, are still not well-defined although most authorities agree that a potential for damage exists.
Although acid rain is not believed to pose a direct risk to human health, there is evidence that the inhalation of acid aerosols can irritate the respiratory tract and aggravate respiratory ailments. The issue is made more complicated, however, by the fact that the effects of acidic pollutants may be difficult to separate from those of other atmospheric pollutants such as ground-level ozone. Human health may also be harmed indirectly by elevated levels of toxic metals in drinking water and food which can occur as a result of acid deposition.
BACKGROUND AND ANALYSIS
A. Historical Perspective
Acid rain is not a new phenomenon although public awareness of the problem is a more recent development. In the mid-seventeenth century, Evelyn (in 1661) and Gaunt (in 1662) noted the influence of industrial emissions on the health of plants and people and the transboundary exchange of pollutants between England and France. They suggested remedial measures including the placement of industry outside of towns and the use of taller chimneys to spread the “smoke” into “distant parts.” In 1872, Smith, in a pioneering publication entitled “Air and Rain: The Beginnings of a Chemical Climatology”, first used the term “acid rain” and described many of the concepts we now consider part of the acidic precipitation problem.
Current awareness of the scope of the acid rain problem has its origins in observations, made in Scandinavia in the 1950s and 1960s, of the increasing acidity of rainfall and of instances of decreasing fish populations. The Scandinavian observations prompted an OECD program to extend measurements over a wider area of Europe. The program, which ran from 1972 to 1977, confirmed the long-range transport of sulphur compounds and pointed to the need for international cooperation to combat the problem.
In Canada, abnormal acidity in precipitation and in Nova Scotia lakes was detected in the mid-1950s. It was hypothesized that the acidity was due to airborne pollution from distant sources. In the mid-1960s, losses of fish populations in lakes southwest of Sudbury, Ontario, were attributed to acidification caused by acid rain.
In 1978, in response to mutual interests and concerns, the Governments of the United States and Canada established a United States-Canada Research Consultation Group to study the problem of the long-range transport of air pollutants (LRTAP). This Group was to study LRTAP and the related phenomenon of acidic precipitation and to aid in the coordination of research studies and the exchange of scientific information between the two countries. A preliminary report released by Environment Canada in October 1979 “identified acidic precipitation as the problem of greatest common concern at the present time.” On 5 August 1980, Canada and the United States signed a “Memorandum of Intent Concerning Transboundary Air Pollution” as a preliminary step in the development of a bilateral agreement on air quality which would deal effectively with such pollution and, at the same time, combat acidic precipitation.
As concern mounted over the widespread damage caused by acid rain, major initiatives to decrease acid rain-causing emissions were introduced. In July 1985, 21 countries including Canada signed the Helsinki Protocol, which called for a 30% reduction of SO2 emissions from 1980 levels as soon as possible and at the latest by 1993. The Canadian Acid Rain Control Program was introduced in the same year. Its objective was to reduce SO2 emissions in eastern Canada by 50% from the 1980 level of 4.6 million tonnes.
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Acid Rain Impacts on Calcium Nutrition and Forest Health: Alteration of membrane-associated calcium leads to membrane destabilization and foliar injury in red spruce
Donald H. DeHayes, Paul G. Schaberg, Gary J. Hawley, G. Richard Strimbeck
BioScience, Volume 49, Issue 10, October 1999, Pages 789–800,