Sustainability indicators link poorer air, water quality, higher GHG emissions to population, economic growth
A "preview" report on four key Canadian environmental sustainability indicators in three categories -air quality, freshwater quality and greenhouse gas (GHG) emissions-points to continuing challenges largely linked to substantial economic and population growth between 1990 and 2005. The third Environmental Sustainability Indicators Highlights report is a precursor to a more detailed report slated for release in December.
The annual report of environmental sustainability indicators is compiled jointly by Environment Canada, Health Canada and Statistics Canada. It tracks specific measures of environmental health in much the same way the Gross Domestic Product (GDP) and other measures track the nation's economic health and well-being. First reported in 2005, the indicators have now been updated for a third year. They are intended to provide Canadians with more regular and consistent information on the state of the environment and how it is linked with human activities.
The air quality indicators focus on exposure to ground-level ozone and fine particulate matter (PM2.5), the leading components of smog and two of the most predominant air pollutants. The freshwater quality indicator is based on the water quality index endorsed by the Canadian Council of Ministers of Environment (CCME), while the GHG emissions indicator comes from Environment Canada's national GHG inventory report prepared annually pursuant to the United Nations Framework Convention on Climate Change.
Canada's overall ozone exposure indicator rose an average of 0.8% per year between 1990 and 2005; this is equivalent to approximately 12% during this period, says the 2007 report. Concentrations in 2005 were highest at monitoring stations in southern Ontario, although high concentrations were also recorded at stations in Alberta and southern Quebec.
The greatest increases in the ozone exposure indicator occurred in southern Ontario and southern Quebec, rising by approximately 17% and 15% respectively. No significant upward or downward trends were noted in the other regions.
The exposure indicator for PM2.5 did not show any significant increase or decrease between 2000 and 2005, the only period for which consistent data are available. Again, the highest concentrations were measured in southern Ontario and southern Quebec.
Transportation, electricity generation, wood burning and the use of chemical products such as paint and solvents can increase levels of ozone and PM2.5. Both compounds have been linked to adverse health effects, with related economic impacts including absenteeism, lower labour force participation and higher health care costs. As well, notes the report, higher concentrations of ground-level ozone can impair productivity in the agriculture and forestry sectors as a result of reduced plant growth and yield.
Not surprisingly, the report documents a significant increase in GHG emissions: Canada's total emissions for 2005 were estimated at 747 megatonnes (Mt) of carbon dioxide equivalent (CO2e), up 25% from 1990; this is also 33% over Canada's Kyoto Protocol target of 563 Mt, or 6% below 1990 levels. The growth in absolute emissions is linked to increased economic activity, which in turn led to greater energy use, during this period.
GHG emissions remained at nearly the same level in 2005 as in 2004, a trend attributed to a substantial reduction in emissions from electricity production together with less demand for heating fuels due to warmer winters and a lower rate of increase in fossil fuel production.
A marked decline did occur in GHG emissions intensity, .e. the amount emitted for each unit of economic activity, which was 17.8% lower in 2005 than in 1990, adds the report.
The freshwater quality indicator assesses water quality as it relates to the protection of fish, aquatic invertebrates and plants, not in respect to water for human consumption and use. Based on data gathered from 2003 to 2005, this indicator shows that guidelines for protecting aquatic life were at least occasionally not met at many monitoring sites across the country. Tests at 359 river and lake monitoring sites in southern Canada rated freshwater quality as "good" or "excellent" at 44% of the sites, "fair" at 33%, and "marginal" or "poor" at 23%.
The presence of phosphorous in water is mainly the result of human activities, coming from sewage, agricultural runoff and industrial wastewater. The report cites phosphorus as a major concern for the quality of surface freshwater in Canada. In southern Canada, it notes, phosphorus levels did not meet the water quality guidelines for aquatic life over half the time at 127 of 344 monitoring sites. The report adds that at least 115,000 tonnes of pollutants (including phosphorus) were discharged directly into Canada's surface waters (both freshwater and coastal) in 2005.
High phosphorous levels in water can result in excessive growth of aquatic plants such as algae and reduce the amount of dissolved oxygen available for fish and other aquatic animals. Some algal blooms can be toxic, threatening livestock and human health.
The indicator results are partly due to the growing Canadian population and economy. Between 1990 and 2005, Canada's population increased by 17%, to 32.3 million. This increase, coupled with economic growth, led to greater resource use and waste production, increased GHG emissions and, in certain cases, more air and water pollution, says the report.
The highlights report of the 2007 Canadian Environmental Sustainability Indicators (16-252-XWE) may be viewed on the StatsCan Web site, www.statcan.ca.