Sulphur Oxide Emissions

In 2010, sulphur oxide (SO_x) emissions decreased by 110 kilotonnes (kt) from 2009 emission levels to 1370 kt, a decrease of 7%. SO_x emissions in 2010 were 1831 kt (57%) lower than in 1990.

There has been a significant drop in SO_x emissions, due in large part to government actions to fight acid rain and federal/provincial and U.S. agreements on capping SO_x emissions by 1994. Reductions were also realized through technological upgrades and new pollution controls for base metal smelters and fossil fuel-fired electricity generation plants, as well as through plant closures. Further emissions reductions were achieved through the implementation of low-sulphur fuels.

Sulphur oxide emissions, Canada, 1990 to 2010

Note: Emissions from natural sources (e.g., forest fires) and open sources (e.g., prescribed burning) are not included in the indicator.
Source: Environment Canada (2012) National Pollutant Release Inventory: Air Pollutant Emissions Summaries and Trends.

Sources of sulphur oxide emissions

In 2010 the largest proportion of SO_x emissions came from fuel for electricity and heating, representing 28% (381 kt) of total emissions, followed by non-ferrous smelting and refining, representing 27% (373 kt) of total emissions. The oil and gas industry emitted 24% (332 kt).

Sulphur oxide emissions by source, Canada, 2010

Note: Emissions from natural sources (e.g., forest fires) and open sources (e.g., prescribed burning) are not included in the indicator.
* The source “Other Industries” does not include SO_x emissions from non-ferrous smelting and refining, as it is presented for the purpose of this chart as a stand-alone source.
Source: Environment Canada (2012) National Pollutant Release Inventory: Air Pollutant Emissions Summaries and Trends.

Sulphur oxide emissions by province and territory

Alberta had the highest SO_x emissions level in 2010, representing 27% (365 kt) of total national emissions (national emissions = 1370 kt). SO_x emissions in Alberta mainly came from the upstream petroleum industry and electric power generating plants. Ontario, with the second-highest emission level, contributed 20% (268 kt) of national emissions, mainly from non-ferrous smelting and refining, and electric power generation plants. Manitoba ranked third, with 14% (197 kt) of national SO_x emissions; non-ferrous smelting and refining was the most important source of emissions in that province.

Sulphur oxide emissions by province and territory, Canada, 2010

Note: Emissions from natural sources (e.g., forest fires) and open sources (e.g., prescribed burning) are not included in the indicator.
Source: Environment Canada (2012) National Pollutant Release Inventory: Air Pollutant Emissions Summaries and Trends.

Sulphur oxide emissions from industrial facilities

Environment Canada’s National Pollutant Release Inventory (NPRI) provides detailed information on air pollutant emissions from industrial facilities. The Canadian Environmental Sustainability Indicators (CESI) program provides access to this information through an online interactive map.

With the CESI interactive map, you can drill down to local areas and obtain details on SO_x emissions specific to reporting industrial facilities.

Source: Environment Canada (2012) National Pollutant Release Inventory: Facility Reported Data.

Related indicators

• National Air Pollutant Emissions