The BC government has released a new report on Air Quality in Courtenay “Patterns of Air Quality and Meteorology in Courtenay B.C. 2011-2016“. The report reconfirms much of what we already know:
- Our area has high levels of harmful fine particulate (PM2.5) levels, particularly in the fall and winter. We frequently exceed BC Air Quality Objectives.
- A significant source of the problem is residential wood heating. Open burning and yard waste fires also contribute to the issue.
- Our highest pollution levels tend to occur at night, during the fall and winter, when winds are fairly calm and coming from the west to northwest. (Note that for the air quality monitor, located at at Courtenay Elementary School, this means our pollution levels are higher when the wind is coming across a wide open school yard; the homes closest to the monitor are to the northeast to east).
The report covers the time period from June 2011 (when the monitor was set up) to December 2016. The report notes that:
“Monthly average PM2.5 concentrations in Courtenay were highest from November to February and lowest in June. It is notable that the largest source of PM2.5 in the valley (forestry hazard abatement burning – see section 1.2.1) is active mainly in October and early November while wood stove emissions, land clearing burns, and residential backyard burning (in the CVRD) continue throughout the winter months. This highlights the fact that emissions inventories only provide one part of the answer. Source proximity to people, quality of the emissions, and timing of the release are other important factors to consider.” (p. 23)
Wood stoves add smoke when meteorological conditions are the poorest
The report describes how meteorological conditions in the evening and pollution sources combine to make conditions worse. ‘Venting’ refers to the potential of the atmosphere to disperse pollutants:
“During the winter period, the afternoon venting window is quite narrow due to reduced surface heating as the daylight period is shorter and the sun angle is lower. The maximum overnight values during the winter months tended to be higher and last for longer. This suggests that fresh emissions such as wood stove smoke were added to the stable layer that is in place during the overnight hours.” (p. 25)
In other words, the time of day when people are most likely to be using their wood stoves, is the same time that smoke is less likely to disperse. Instead it sticks around for all of us to breathe, for the whole evening and night, day after day.
Let’s stop studying, and start acting!
The issue of wood smoke in Courtenay and the Comox Valley as a whole as been studied and reported on far more than most BC communities. There is no question that we have a serious air pollution problem, which is also a public health problem. As the report recommends:
“Additional measures to address sources of wood smoke in the Comox Valley should be considered. Action is needed to manage smoke emissions from both large-scale open burning and residential back yard burning, as well as emissions from wood-burning appliances.”
Enough with the studies: can we please get on with action?
We need political leaders who have a clear vision of having winter air that is as clean as our summer air, and the will to take concrete steps to make it a reality. Exchanging a handful of wood stoves each year will not get us there in this decade or the next (see our post on “Rebates for new wood stoves: Not effective solution to pollution.”). How long are we expected to wait before we can all breathe clean air in our communities?
Read the full report: Patterns of Air Quality and Meteorology in Courtenay B.C. 2011-2016
Read newspaper article in the Comox Valley Record about the study “B.C. government releases report on Courtenay air quality and meteorology patterns“