Ozone is a naturally occurring constituent of the atmosphere. In the upper atmosphere it absorbs solar energy in the ultraviolet band and significantly reduces the amount of harmful radiation that reaches the earth’s surface. In the lower atmosphere ozone can have a number of adverse effects on materials, vegetation and human and animal health.
Ozone concentrations in the lower atmosphere are affected by mixing rates between the upper and lower atmospheres and by ground-level ozone formation rates. Ground-level ozone formation involves complex interactions between nitrogen oxides, volatile organic compounds (VOCs) and sunlight.
Natural background concentrations of ground-level ozone are difficult to estimate but are likely in the 25-40 ppb range.1 Higher ground-level ozone concentrations occur during summer periods in areas with elevated nitrogen oxide and VOC levels including urban regions and areas affected by industrial emissions. The management of nitrogen oxide and VOC emissions can significantly reduce ground-level ozone concentrations.
In recent years there has been a strong focus on developing national and provincial ozone standards and management frameworks. The Regional Municipality of Wood Buffalo Area (“the Region”) is largely basing its ozone management plan on this recent body of work. The application of the national and provincial frameworks to the region is considered the focus required at the present time.
The Region's Ozone Management Plan establishes a framework for addressing issues and priorities related to ozone and its precursors in the Region.