Acid Rain as Urgent Environmental Issue

Introduction

Acid rain, or acid deposition is rain water with elevated levels of hydrogen (H+) ions. Acid rain refers to the ways in which acid moves from the atmosphere to the earth's surface. It is transboundary and involves the falling of sulfuric or nitric acid. There are two different forms of acid deposition, one of them is wet deposition: acid rain, snow, and fog and dry deposition, which falls as separate acidic particles or gases.

Acid rain occurs as a result of high pollution levels in the atmosphere. It is a chemical reaction caused as a result of emissions of sulfur dioxide and nitrogen oxides reacting with oxygen, water vapour, carbon dioxide and other substances in the atmosphere to form sulfuric and nitric acids. Sunlight is a factor that increases the rate of these reactions.

The emission of these chemicals alters how gases in the atmosphere react with each other. Burning fossil fuels such as; oil, gas and coal, generate sulfur dioxide and nitrogen oxide gases and releases them into the atmosphere. Acid rain is most prevalent in areas of high sulfur dioxide and nitrogen oxide emissions. When air becomes more polluted with sulfur dioxide and nitrogen oxides, the acidity increases. Only ten percent of the pollution responsible for acid rain is from natural causes.

Measuring the Acidity of Rainwater

Acidity is a measure of the concentration of hydrogen atoms in a solution. The pH scale measures the alkalinity and acidity of solution. A substance is considered to be an acid if they are below a pH of 7. The acidity of rain water comes from; carbon dioxide, nitrogen oxide and sulphur dioxide. Pure water is neutral and has a pH of 7. Rain water, due to the carbon dioxide in the air, is weakly acidic and has a pH of 5 to 6. Carbon dioxide contributes to the natural acidity of rainwater, as when it dissolves in water, the reactants are rearranged to form a carbonic acid.

Sulfur dioxide and Nitrogen oxides are bi-products generated from the burning of fuels and gases. Sulfur dioxide; So2 is a chemical compound. It is released into the atmosphere through industrial activity. So2 is formed when materials containing sulfur are burned. Sulfur dioxide is a form of atmospheric pollution and if inhaled, can cause irritation to the nose, throat and airways.

Nitrogen oxides has a chemical symbol of No2. It is a highly reactive gas released into the earth's atmosphere through manufacturing, oil refineries and fuel emissions from cars, trucks, busses and power plants. Inhaling air with a high concentration of Nitrogen oxides can disturb the functioning of the lungs and contribute to asthma, and other damaging respiratory conditions.

Adverse Effects of Acid Rain

Acid rain has many adverse effects on the earth's ecosystem. Acid rain percolates into soils, dissolving magnesium or calcium; plants vital nutrients and releases toxic substances that influence how plants absorb water. Acid deposition also weakness trees, damages their leaves and limits the nutrients available to them. The inimical consequences of acid rain can be further observed in marine environments. Acid rain falls directly on aquatic habitats, and causes these environments to become more acidic. As the pH level of these areas decrease, the numbers and species of fish, plants and animals living in these aquatic habitats depreciate.

Acid rain does not directly affect human health. Sulfur dioxide and Nitrogen oxides react in the atmosphere to form sulfate and nitrate acids that can be inhaled by people. Scientific studies have shown a relationship between these particles and the effects they have on human health. Inhaling sulfur dioxide and Nitrogen oxides, can cause; heart attacks, increase the risk of heart disease, and affect lung function.

Acid rain impairs any vulnerable material it lands on. Acid rain causes erosion to the surfaces of buildings and vehicles. The effects of acid rain can be most notably observed on limestone, marble or sandstone as these rocks dissolve in acids and are therefore particularly affected by air pollution and acidic rain.

History and Present of Acid Water

The earliest account of acid rain was in 1852, by Robert Angus Smith. Robert was able to indicate the relationship between acid rain and atmospheric pollution. In the late 1960s scientists in England conducted further research into the chemical reaction, central causes, and consequences of acidic rain. Since the industrial revolution in the 1960s, emissions of Sulfur dioxide and Nitrogen oxides have increased and the acidity of rain as a result of the establishment of more industrial and energy generating facilities, has also increased.

Scientists continue to perform studies into the complications associated with acid rain, and develop products to minimise the effects of Sulfur dioxide and Nitrogen oxides. Further research is currently being conducted into more innovative and environmentally sustainable ways to burn fuels in factories.

Acid Rain, the Economy and Industries

Acid rain is a consequence of industrial production. Ninety percent of acid rain reactants are produced in factories. The only commercial benefit involved in the production of acid rain is the reduction in the cost of controlling the reactants released. So2 scrubber are regularly installed in industrial factories to prevent the emissions of sulfur dioxide into the atmosphere, however it is cheaper for these industries to let the reaction happen in production, than to install these preventive devices. Acid rain can weaken the production of crops and pollute aquatic environments, poisoning fish. This creates further financial burdens in communities, business and the economy as a consequence of the damage inflicted by acid rain.

Conclusion

From the research conducted, I have been able to further my perceptions of the central causes and consequences of acid rain. Acid rain is water with elevated levels of hydrogen ions and can have adverse effects on the earth ecosystem, building materials, natural landforms and marine species.

Although acid rain does not directly affect human health, the emission of sulfur dioxide and nitrogen oxides that react in the atmosphere to form sulfate and nitrate acids, can provoke irritation to the throat, ears and airways and damage to the heart and lungs. It is evident from the research conducted, that if in the future industrial facilities continue to burn fuels that generate sulfur and nitrogen oxides, the extent of the damage and the frequency of acid rain is going to increase. If scientists continue to perform studies into new ways of reducing the emissions of SO2 and NO2 in the atmosphere and develop new preventive devices, it may minimise the effects of acid rain in the future.

It is however, evident that acid rain has already had many damaging consequences on the earth's ecosystem and after evaluating the evidence, I can conclude that the only benefit of acidic rain is the reduction of methane emissions in the environment, helping to reduce the effects of global warming.