Wildfire smoke has become a regular feature of summertime living on the West Coast over the past few years.
In Greater Victoria, many are coming to see breathing smoke for the month of August as “the new normal.”
For a lot of people in Victoria, climate change is still a rather abstract concept, something they’ve heard a lot about but not something they feel has made its presence felt in their own personal experience in a concrete way.
For many, the annual period of wildfire smoke is the arrival of climate change in their lives in an immediate way, their first explicit, unmistakable experience of its effects.
The incidence of wildfires has been increasing in Canada, and has doubled since the 1970s. Wildfire seasons are starting earlier and lasting longer.
In British Columbia, four of the past five years have been above the 10-year average in terms of the total number of hectares burned by wildfire, indicating an overall pattern of increase in recent years. Both of the past two years have been record-setting wildfire seasons in B.C.
The main driver of this increase in wildfire is climate change. Climate change has brought more drought, more extreme heat and lower snowpacks, all of which create greater potential for wildfire.
Climate change has also resulted in greater incidence of severe thunderstorms, with lightning, which is the cause of the majority of wildfires in B.C. The three factors causing wildfire — fuel, ignition and weather — are all present in an environment with parched vegetation, greater frequency of lightning and hot, dry weather conditions.
The gases emitted by wildfire — mainly carbon dioxide, methane and nitrous oxide — are all greenhouse gases, contributing to global warming.
Wildfire is, then, part of a positive feedback loop in which it is both a result and a cause of climate change, by virtue of its production of greenhouse gases.
In addition, wildfire kills large numbers of trees every year, trees that would otherwise be part of the planetary carbon sink that is the world’s forests. Furthermore, the particulate carbon suspended in wildfire smoke makes its way to the Arctic, where it darkens the sea ice, causing it to absorb more heat and hastening the warming of the planet’s oceans.
As well as resulting from climate change, then, wildfire also contributes to climate change in important ways.
The principal health concern involving wildfire smoke is the inhalation of particulate matter. Fine and ultra-fine particulate matter (particles 2.5 micrometres or smaller) reaches the lungs and potentially the bloodstream, and can penetrate tissues including the brain.
Eighty to 90 per cent of the mass in wildfire smoke is this fine or ultra-fine particulate matter. Coarse particulate matter is filtered out in the upper respiratory tract, and can accumulate there and cause inflammation and respiratory problems.
Short-term effects of breathing wildfire smoke can include respiratory problems, immunological inflammatory reactions and eye irritation.
Breathing wildfire smoke exacerbates asthma and chronic obstructive pulmonary disease, and can also cause bronchitis and pneumonia. In the longer term, exposure to wildfire smoke can cause asthma and cancer, and maternal exposure during pregnancy has been found to be related to childhood asthma.
Children, especially young children, are among the four population groups most affected by wildfire smoke in the air, along with seniors, smokers and people who already have respiratory problems, such as asthma or COPD.
While this hasn’t been established by research, it stands to reason that children growing up breathing wildfire smoke every summer will have shorter life expectancies than preceding generations.
Adaptations in forestry practices, such as increased use of prescribed burns to reduce accumulated fuel and mimic the effects of naturally occurring wildfires, can reduce uncontrollable mega-fires to some degree.
But the only real hope we have of substantially reducing wildfire, human exposure to wildfire smoke, and the damage to wilderness and property caused by wildfire, is through addressing the rampant consumption of fossil fuels that drives changes to the climate and ultimately places all life on the planet at risk.
In view of the UN Intergovernmental Panel on Climate Change’s warning last year, that the world has until 2030 to reverse the growth curve of fossil fuel use and turn the curve downward in order to avoid the worst-case scenarios, the world needs to act in unison with a Second World War-scale effort to bring about, in the words of the IPCC, “rapid, far-reaching and unprecedented changes in all aspects of society,” before it’s too late.
Rob Duncan is an organizer with Extinction Rebellion Vancouver Island and a former academic social scientist.