Transboundary Pollution: acid rain
Acid rain or more precisely, acid deposition, is the increased acidity of rainfall and dry deposition as a result of human
activity. Rain is naturally acidic, owing to carbon dioxide in the atmosphere, with a pH of about 5.6. However the pH of
“acid rain” can be as low as 3.0.
The major causes of acid rain are the sulphur dioxide and nitrogen oxides produced when fossil fuels (coal, oil, gas) are
burned. Sulphur dioxide and nitrogen oxides are released into the atmosphere, where they can be absorbed by moisture
and become weak sulphuric and nitric acids.
Coal-fired power stations are the maor producers of sulphur dioxide, vehicles, especially cars, are responsible for most
of the nitrogen oxides in the atmosphere. Some come from the vehicle exhaust itself, but others when the exhaust gases
react with the air.
Dry deposition typically occurs close to the source of emission and causes damage to buildings and structures.
Wet deposition, by contrast, occurs when the acids are dissolved in precipitation, and fall at great distances from the
sources. Wet deposition has been called a “transfrontier” or “transboundary” pollution, as it crosses international
boundaries (eg UK to Scandinavia 1980s)
You must be able to discuss transboundary pollution (acid rain) in terms of its effects and solutions by examining
Produce detailed notes on the effects of acid rain
Please Note: If taking quotes or ideas directly from a website remember to acknowledge your source.
Eg. “Many parts of western Scotland and Wales were severly hit by acid rain in the 1980s because of sulphur produced by shipping,
along with the effect of emissions from North America - transboundary acid rain” (BBC 2010)
Or BBC (2010) suggests that emissions from North America in the 1980’s caused problems with acid rain in Western Scotland
As this is from a website you would reference it as:
BBC (2010) viewed 10 March 2010 <http://news.bbc.co.uk/2/hi/uk_news/scotland/1697932.stm>
This is an important habit you must get into, especially with Internal Assessments and Extended Essays coming soon –
failure to correctly reference sources is classed by IB as plagiarism. Universities also expect this. For more information on
referencing sources including books and journals see:
Various methods can be used to try and reduce the damaging effects of acid deposition. Research such methods and
produce some notes to explain how this can be done (try to avoid Wikipedia!)
Case Study: produce a brief summary of an example where transboundary acid deposition has taken place. Include a
map and a brief description of the problem and how it was solved . This case study can then be used to support your
discussion should you have to answer a question on this in an exam.
Links: (a good starting point you may wish to your own as well)
TED Case studies: Japan’s air pollution Acid Rain in the UK
US Environmental Protection Agency: Effects of Acid Rain Acid Rain in Canada
Young People’s Trust: Causes, effects and solutions to Acid Rain Canada Case Study: Acid Rain
BBC News: Study shows acid rain improvement
As we have seen through our case studies on Bhophal, Sea Empress and Acid Rain there is a need for us to be more
aware of the damage that can be done to the environment as a direct result of our activities.
There are many active players in the work of environmental awareness and conservation. These include:
Individuals (eg Gerald Durrell and the Durrell Wildlife Conservation Trust. See: http://www.durrell.org/)
Groups (eg Greenpeace and the World Wide Fund for Nature)
Public Servants, such as politicians and scientists (eg Al Gore, former US vice-president, author of an Inconvenient
Truth; and Dian Fossey, made famous by the film Gorillas in the Mist)
In most cases there is a conflict between the need for economic development and the need for environmental
conservation and management. Dian Fossy argued for the protection of the mountain habitats in Rwanda and Brundi
that are home to the great silverback gorillas. On the other hand, population growth, civil conflict and the illegal trade in
forest products led to a decline in forest cover and the reduction of gorilla’s habitat.
There is an urgent need for strategic thinking, especially in some of the world’s most valuable biomes, such as the
Tropical Rainforest and Coral Reefs. This needs to be done in a sustainable way, with the cooperation of the indigenous
Research the role of Greenpeace and the World Wide Fund for Nature (WWF). What do they aim to achieve? Give some
examples of their work. What is it they attempt to achieve?
Greenpeace has received criticism for their work. Find out why