Plan of Action :: Links
The issue of air pollution, like air itself, is hard to grasp.
Often simply mistaken as a matter of clean versus dirty, air pollution actually pertains
to a wide variety of environmental issues, some of which are closely related and some of
which are almost entirely independent. Various air pollutants can have local, regional,
and global impacts, and can stay in the atmosphere after being emitted anywhere from a few
hours to thousands of years.
The most salient air pollution issue at present is increasing greenhouse gas
(GHG) concentrations in the atmosphere, which are a major contributor to anthropogenic
climate change. The latest report by the Intergovernmental Panel on Climate Change (IPCC)
notes that the current atmospheric CO2–equivalent concentration is about 380ppm – up from
320ppm in 1965 – and that we will need to stabilize this concentration under 500ppm by 2100
in order to avoid risking serious global impacts, such as widespread water shortages, famine,
and disease. Doing this will require worldwide GHG emissions to reduce by at least 50% by the
year 2050. GHG emissions primarily come from fossil fuel combustion and the release of other
substances – such as methane, nitrous oxide, and halocarbons – from various sources.
Interestingly, carbon dioxide is often not actually considered a pollutant; increased carbon dioxide
concentrations actually help plants grow, and will not reach levels that have any direct negative impacts
on living beings. The only adverse effect of rising CO2 concentrations – albeit and enormous one –
is the anthropogenic climate change it is causing. Natural greenhouse gases in the atmosphere (which both CO2 and methane are) in their normal concentrations actually help keep the global climate livable – the earth
would be about 33oC colder otherwise!
The distinction above is an important one, because there are other air pollutants that are actually
harmful in any concentrations. Sulfur oxides and nitrogen oxides (SOx & NOx) released from poorly filtered
fossil fuel combustion emissions cause acid rain, and they contribute to two different varieties of smog.
The mixture of sulfur dioxide with smoke forms classic smog, and the reaction of nitrogen oxides with volatile
organic compounds (VOCs) and sunlight forms a mixture of airborne particulate matter and tropospheric ozone known
as photochemical smog, which is common in large urban areas. Both forms of smog have serious adverse health effects,
primarily by causing a variety of respiratory diseases. Finally, the release of chlorofluorocarbons (CFCs) cause the
depletion of the ozone layer, which results in hazardous amounts of ultraviolet radiation being transmitted through the atmosphere.
North America in general has already taken great steps to address most air pollution issues. The Montreal Protocol, an international
treaty that entered into force in 1989, phased out the use of ozone depleting substances, and government agencies regulate the emissions of
acid rain, smog forming, and other toxic pollutants. The main class of air pollutants that has not yet been adequately regulated is GHGs.
The Kyoto Protocol entered into force in 2005, but at present few countries look to be hitting their targets, including Canada
U of T Scarborough observes all regulations required by law,
which leaves GHG emissions reduction as our main task.
We largely strive to reduce our emissions through reduced energy consumption, as we generally do not have the ability to change the carbon intensity of power generation on campus – we import it from off–campus sources. We are working towards the integration of higher efficiency equipment on campus, and promote the use of public transit to all of our staff, students, and faculty. In partnership with Evergreen, U of T Scarborough also undertakes regular planting initiatives, which aid in carbon sequestration and the improvement of local air quality.
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