Acid rain is formed when sulfur dioxide and nitrogen oxides emitted from fossil fuel combustion react with water, oxygen, and sunlight in the atmosphere to produce dilute sulfuric and nitric acid. These acids can be transported long distances through wet and dry deposition, affecting areas far from the source of emissions. Acid rain damages trees, soils, lakes and aquatic life, and accelerates the decay of buildings and statues. While some countries produce most acid rain pollution, prevailing winds often carry the acids to other downwind nations, making it an international issue requiring global cooperation to reduce emissions.

1. Acid Rain Ref: GCSE Geography pg 60

2. The branch on the left is from a tree in the Black Forest in Germany.

5. The Formation of Acid Rain Burn fossil fuels in Transport, Industry, Homes, power stations The rest reacts with sunlight and ozone in the atmosphere; nitric (HNO 3 ), and sulphuric acid (H 2 SO 4) are produced Gas, Oil, Coal Some falls back to Earth close to the source as dry particles, gas and aerosols (NO x and SO 2 ) (dry deposition) NO 2 SO 2 It is dissolved in the moisture in the atmosphere making 2H + and SO 4 2 _ and can be carried large distances before falling as rain or snow (wet deposition) TRANSBOUNDARY POLLUTION H 2 O H + NO 3 _ SO 4 2 _

7. Acid Deposition Acid deposition involves the deposition of both wet and dry acidic components

10. The effects…

11. The effects … Acids activate aluminium from the soil which leaches into water and fish die. Drinking water is contaminated Acid rain destroys tree roots. The trees are then more likely to suffer from drought and disease The chemical weathering of buildings, statues and stone objects. Chemical reactions release toxic metals, particularly aluminium into solution Soils become more acidic. Unless lime is added the quality of the crops is reduced

12. Why is acid rain an international issue?

16. How might the effects of acid rain be reduced? Burning coal which contains less sulphur Remove sulphur from coal before it is used Remove sulphur from waste gases after it is used (Flue gas desulphurisation) Using unleaded petrol But … It costs Tales a long time to phase out thermal power stations Impact on coal mining industry as demand falls International agreements to reduce sulphur dioxide emissions Add lime to lakes affected by acidification Switch to alternative energy supplies Energy conservation methods