Much of Alberta has become inundated with smoke from forest fires burning in British Columbia, carried east by upper level winds. To be fair, we deal with at least a few smoky days every summer. It is still uncomfortable, however, and many people can be adversely affected. People with respiratory difficulties are, of course, most at risk. The Alberta government has thus issued an advisory, recommending that people avoid strenuous physical activity outdoors.
Air Quality Measurements and the AQI
Air quality is monitored for various regions in Alberta. The air quality index (AQI) is provided by Alberta Environment (AENV) as a “qualitative measure of outdoor air”. The overall AQI for a given region is determined by the worst of several pollutants: carbon monoxide (CO), oxides of nitrogen (NOx) measured as nitrogen dioxide (NO2), ozone (O3), sulphur dioxide (SO2), and fine particulate matter (PM2.5).
Of course, any index requires a scale. The AQI scale is as follows:
Each pollutant above is measured and assigned a value. The highest value becomes the rating for that region. Also, it is important to note that each province has its own independent system. It is therefore impossible to reliably correlate across the country.
For the purpose of air quality monitoring, the province of Alberta is divided into nine regions, called airsheds. Eight airsheds are up and running, and the other is currently under development (according to the Clean Air Strategic Alliance (CASA) website, but who knows how often that site is updated). The nine regions are:
- Calgary Regional Airshed Zone (CRAZ) – Calgary area
- Lakeland Industry and Community Association (LICA) – Bonnyville, Cold Lake, St. Paul and region
- Fort Air Partnership (FAP) – Fort Saskatchewan and region
- Palliser Airshed Society (PAS) – Medicine Hat and Redcliffe
- Parkland Airshed Management Zone (PAMZ) – Red Deer, Rocky Mountain House, Sundre, Banff, and surrounding regions
- Peace Airshed Zone Association (PASZA) – Grand Prairie and region
- West Central Airshed Society (WCAS) – Jasper, Hinton, Edson, Lake Wabamun, Drayton Valley, Pigeon Lake, and surrounding regions
- Wood Buffalo Environmental Association (WBEA) – Fort McMurray and the Wood Buffalo region
- Alberta Capital Airshed Alliance (ACAA) – Edmonton Region (in development)
Alberta has basically followed the lead of Saskatchewan in developing airsheds. The regions covered by Alberta’s airsheds should be familiar to those who remember the old health regions – they’re very similar.
The Calgary Regional Airshed Zone Society is a “non-profit association with members from government agencies …, non-government organizations, industry and the public.”
The most disturbing thing to my mind is that the AQI rating for the entire CRAZ is based on three active monitoring stations located in Calgary (see the map to the right). However, there are other active monitoring stations in southern Alberta: one in Lethbridge, and another (for the Palliser Airshed Society) in Medicine Hat (which apparently is not currently working).
Of course, there is also the problem that the equipment is old (1970s vintage), likely resulting in increased maintenance costs.
Each airshed zone must submit its data to the Alberta Ambient Air Data Management System – CASA’s data warehouse. It is designed to be a central data repository for Alberta’s 140 active monitoring stations. Should you wish to view the data for yourself, feel free to navigate to the website at http://www.casadata.org.