Monthly Archives: March 2015

Team Question 4


What are the issues in the country you selected ?

The country we have selected is Canada.

Acid rain has caused many species of fish, insects, aquatic plants and bacteria develop reproduction difficulties. Some of the animals even lose their lives. This will lead to a fall in the population of these aquatic organisms which will eventually affect the food chain. Dwindling populations of insects and small aquatic plants and animals are especially serious because the entire food chain is affected.

Does the acid deposition originate outside the borders of the country? 

Acid rain refers to contaminated rainwater. The contamination of rainwater is caused by the chemicals that were emitted into the atmosphere, through industrial and automobile emissions.

On a daily basis, human activities — industrial, agricultural and residential — cause vast quantities of natural and synthetic chemicals to be emitted into the atmosphere. Once released, the substances are dispersed throughout the globe by air currents that know no boundaries — provincial or international. This phenomenon is known as the long-range transboundary air pollution (LRTAP).Over time, these emissions expose human beings, wildlife and resources to diverse quantities and mixtures of air pollutants. The resulting harm is difficult to evaluate, since it occurs over varying time frames and over vast areas having differing degrees of sensitivity. The reversibility of the damage is not yet well understood. Acid rain is known as one of the most publicized LRTAP phenomena. Therefore, it is difficult to conclude that acid deposition originate outside the borders of the country.

In the atmosphere, chemical compounds such as nitrogen oxides and sulfur dioxide will combine with water vapour to form nitric acid and sulfuric acid respectively. When these acids  mixed with rain, these acids fall as acid rain. Without rain, the particulate matter slowly settles to the ground as dry deposition. Together, wet and dry deposition of acidic substances is known as acid precipitation.

In Canada,  sulfur dioxide is emitted by non-ferrous metal smelters and coal-fired generators. Motor vehicles and, to a lesser extent, coal-fired generators, are the major sources of nitrogen oxides. Approximately half of the wet sulfate deposition in eastern Canada comes from the United States, while about ten percent of the deposition in the northeastern United States comes from Canada.


Reference: Acid Rain (Archived), from Environment Canada