Environmental Sustainability Indicators document rising levels of GHG emissions, smog precursor compounds
Between 1990 and 2004, Canada's overall concentrations of ground-level ozone, a key component of smog, increased by an average of 0.9% per year, while greenhouse gas (GHG) emissions rose by 27% during the same period. In addition, the second annual Canadian Environmental Sustainability Indicators report reveals that water quality guidelines for aquatic life are being exceeded, at least occasionally, at a majority of selected monitoring sites across the country.
The report, prepared by Environment Canada, Statistics Canada and Health Canada, provides updates on three indicators: air quality, GHG emissions and freshwater quality. The indicators are intended as annual measuring sticks by which governments and the public can track trends in the three areas.
The air quality indicator focuses on human exposure to fine particulate matter (PM2.5) as well as ground-level ozone. In addition to being smog precursors, both substances are of concern because there are no established thresholds below which they pose no risk to human health. These pollutants can travel into the lungs, causing health problems ranging from minor respiratory discomfort to hospitalizations and for those at high risk, premature death.
At the national level, the ground-level ozone indicator showed year-to-year variability from 1990 to 2004, with an average annual increase of 0.9%. The highest concentrations were found at monitoring stations in southern Ontario, followed by eastern Ontario and Quebec. The report says ground-level ozone values have shown an increasing trend in southern Ontario since 1990, while other regions have shown either a decrease or no noticeable increase.
The PM2.5 indicator, which covered the period from 2000 to 2004, shows that levels have not changed substantially over this time period. In 2004, the highest levels were recorded in southern Ontario, with high levels also found in some areas of eastern Quebec. The limited number of years covered by this indicator does not yet permit a national trend analysis.
The report lists transportation and industrial emissions as the main sources of these air pollutants, but notes that wood burning for home heating is also a significant source, especially in the winter. Dust from wind erosion and ash from forest fires are natural sources of particulate matter.
Health Canada is researching the feasibility of developing and reporting an integrated environment and health indicator (Air Health Indicator) that would be based on the combined health risks of exposure to several air pollutants, including ozone and PM2.5. Earlier this fall the department, in collaboration with Environment Canada and local governments in British Columbia, also began pilot-testing an Air Quality Health Index, designed to provide air quality forecasts in a manner similar to the more familiar UV Index (EcoWeek October 30, 2006).
The greenhouse gas emissions indicator summarizes total national emissions of greenhouse gases. These emissions increased 27% from 1990 to 2004 to an estimated 758 million tonnes of carbon dioxide equivalent. This exceeds the greenhouse gas reduction target of the Kyoto Protocol by 35% (or about 200 million tonnes). Alberta and Ontario recorded the highest proportion of GHG emissions in 2004, notes the report.
It further points out that Canadians actually emitted more greenhouse gases per capita in 2004 than in 1990, as annual emissions per person rose 10% over that period to reach 24 tonnes. Canada now ranks among the world's highest per-capita emitters, behind only Australia and slightly higher than the United States, producing approximately 2% of global greenhouse gases with only 0.5% of the world's population.
At the same time, however, Canada's emissions intensity, measured as emissions per unit of Gross Domestic Product (GDP), improved by 14%. Canada has become more efficient, but economic and population growth means that total emissions have risen sharply.
Energy consumption (including road transportation, oil and gas industries and fossil fuel-fired electricity generation) rose by around 25% between 1990 and 2004. Energy accounted for 82% of total Canadian GHG emissions in 2004 and 91% of the growth in emissions from 1990 to 2004. GHG emissions from the oil, gas and coal industry increased 49% from 1990 to 2004, reflecting rapid growth in the production and export of crude oil and natural gas. Emissions from road transportation rose 36% over the same period as the types of personal vehicles shifted from automobiles to minivans, sport utility vehicles and small pickup trucks.
Emissions from thermal electricity and heat production grew 37% from 1990 to 2004, driven primarily by a rising demand for electricity and an increase in the use of fossil fuels for electricity generation relative to non-emitting sources such as nuclear and hydro.
The report notes that an analysis of 2002 data suggests that 46% of Canadian industrial GHG emissions in that year can be attributed to exports, reflecting Canada's resource and energy-based economy.
The freshwater quality indicator covers the period from 2002 to 2004 and focuses on the ability of Canada's surface waters to support aquatic life. Conclusions are based on monitoring results from 340 selected sites across southern Canada, including the Great Lakes, plus (for the first time) 30 sites in northern Canada.
The report indicates that water quality in Canada is under severe pressure from a range of sources, including human settlement, agriculture and industrial activities, and that degraded water quality is affecting both aquatic life and human uses of water.
Freshwater quality at the southern sites was rated as "good" or "excellent" at 44% of sites, "fair" at 34% and "marginal" or "poor" at 22%. Freshwater quality measured in the Great Lakes in 2004 and 2005 was rated as "good" or "excellent" for Lake Superior, Lake Huron, Georgian Bay and eastern Lake Erie, "fair" for central Lake Erie and "marginal" for western Lake Erie and Lake Ontario. At the 30 northern Canada sites, freshwater quality was rated as "good" or "excellent" at 67% of the sites, "fair" at 20% and "marginal" or "poor" at 13%. These ratings are based on the Water Quality Index (WQI) endorsed by the Canadian Council of Ministers of Environment (CCME) in 2001.
At least 110 000 tonnes of pollutants were directly discharged to Canada's surface waters (both freshwater and coastal) in 2004, based on figures from Environment Canada. Nitrate ion and ammonia were the pollutants released to water in the largest quantities in 2004. Other more highly toxic substances, such as mercury, are released in much smaller, but nevertheless significant, amounts, adds the report.
Different water quality variables were measured at different locations across the country, depending partly on the priorities of the various monitoring programs, the kind of human influences in the area and the characteristics of the aquatic ecosystems. The variables most typically included in calculations across Canada were phosphorus (334 sites), ammonia (276), nitrates (260), pH (230) and zinc (211). Of those sites, phosphorus measurements exceeded guidelines at least once at 81% of sites, ammonia at 18% of sites, nitrates at 28%, pH at 25% and zinc at 27%. Moreover, 38% of sites that included phosphorus had phosphorus measurements above guidelines in more than 50% of collected samples.
The three environmental indicators are also examined in the context of broader socio-economic issues. The report list three fundamental ways in which the indicators are connected:
1. Many of the same social and economic forces drive the changes in the indicators.
2. Some of the same substances affect all three indicators.
3. The indicators reflect stresses in many of the same regions of the country.
Linking these indicators and connecting them to other socio-economic and environmental information can guide policy decisions that better address environmental sustainability, economic performance and quality of life, says the Statistics Canada report. Future reports in this series will reflect improvements in development of the individual indicators as well as a more complete transition to reporting of the indicator results as a data set that is integrated with other information on the environment, economic performance and social progress. The long-term goal is better decision-making that takes into full account environmental sustainability, says the report.
The 2006 Canadian Environmental Sustainability Indicators report may be viewed on the StatsCan Web site, www.statscan.ca.