Geo Notes – Oct/12
Environmental Challenges for Canada
- All human activities affect the environment. Often, industrial activities or the burning of fossil fuels
contribute to air pollution, acid rain, smog, and global warming. Smog and acid rain are two products of air
pollution. The top three provinces by industrial emissions are AB, ON, and SK.
- Traditionally we believed that resources were infinite. Nobody was concerned about trees growing back.
There has been widespread deforestation of forests. The great lakes have a seemingly infinite capacity to
accept garbage, which results in pollution. The result has been widespread environmental deterioration.
- Acid rain (regional scale): Acid rain is precipitation with a higher than normal level of acidity and it affects
the forests and lakes of ON, QC, and Atlantic Canada. The major cause of it is the use of fossil fuels in industry
and transportation. The impact area is downwind (east) of the source or origin. The source area is the
industrial heartland of North America. The hardest hit areas are underlain by the Canadian Shield.
Sedimentary rock is capable of neutralizing acid rain, but the Canadian Shield isn’t made of sedimentary
rock, so there is no buffering there. In urban areas, it causes damage to exposed stone (limestone, marble) of
buildings and monuments.
- Smog (local scale): Smog or air pollution is a major problem facing large cities. The source of smog is cars
and coal-burning thermal generating plants. Smog is a mixture of smoke, CO2, and sulphur dioxide. A key
area for smog is southern Ontario because of the number of cars. Wind dissipates smog the further away you
get from the source.
- Global warming (national scale): The general consensus is that it’s occurring. Increasing levels of
greenhouse gases in the atmosphere from human use of fossil fuels is leading to increasing atmospheric
temperatures. Carbon dioxide is a greenhouse gas and it is able to absorb radiation from the earth, and this
is known as the greenhouse effect. As more CO2 is added to the atmosphere by the burning of fossil fuels, the
greenhouse effect will increase, more radiation will be absorbed rather than be reflected back out into
space, and temperatures on earth will increase. This is a complex situation though – what natural factors
might alter the warming trend in the future. Atmospheric warming can be countered by other phenomena,
however. Increasing particulate matter in the atmosphere (dust from industry, dust from volcanic
eruptions) may contribute to cooling. Temperature change is expected to be greatest in higher latit