The severity and frequency of forest fires have increased broadly, particularly in provinces like BC and across Canada — but not just here. Around the world, wildfires have caused remarkable damage to property, the forestry industry, water supplies, ecosystems and human health. In Canada, the average annual area burned (~25 million ha) has more than doubled since the late 1960s.
Research shows that wildfire risks, fire-spread potentials and the lengths of fire seasons have increased due to climate changes including warmer temperatures for longer periods, drier fuels and more lightning. Lightning is responsible for 45 per cent of all fires and increases in frequency ~10 to 12 per cent with every degree (°C) of warming.
The combined effects of climate change, development in the wildland-urban interface and fuel accumulation provide a foundation for fires that can become large and catastrophic, with health and safety threats that stretch far and wide. As climate changes are forecast to continue and previously unusual fire seasons are projected to become ordinary, what can we do to manage wildfires and their risks?
How to fight fires
Amp up defensible space and prescribed burns; shift development footprints
Municipal and district planning, citizen support and intergovernmental coordination are required for broad mitigation of fires. Strategies for physically managing fires have traditionally included developing defensible space around structures and along wildland-urban interfaces. These spaces are designed to minimize the available fuel and impede the spread of fire, which is critical as burns are getting hotter and faster. Defensible space is particularly important to embrace around whole communities, not just individual dwellings.
Fires can become especially catastrophic when “ladder fuels,” which are dense stands of vegetation at different heights that have accumulated over several years, carry the fire from the ground to the canopy and allow rapid spread. Also, unlike humans and machinery, fires move faster uphill — something to consider as we alter slopes, build and plan evacuation routes.
Forest thinning (when fuels are especially dense) or prescribed burns can keep ladder fuels, other combustible organics and the risk of extremely dangerous and fast-moving fires at bay. Prescribed burns are understandably hard to stomach for nature lovers and locals; however, the alternative disasters are far worse.
In places such as California, which has experienced some of the worst fires in recent memory, planners and policy makers are doubling down on difficult decisions as they reckon with land use changes, zoning changes and incentives to shift development footprints into safer spaces. These changes return to concepts such as expanding community-wide requirements for defensible spaces and, in some cases, denying permissions to rebuild in fire-prone areas.
Make bad bogs good bogs
Dried-out wetlands, much like the drained peatland that fire evacuees watched burn along parts of Highway 63 out of Fort McMurray in 2016, are highly combustible and can turn a potential firebreak into an easy fire path that burns faster and longer. Dry peatlands with unchecked spruce tree growth shade out sphagnum moss, which is naturally fire-resistant when healthy and waterlogged, and further desiccate the wetland. These dried-out wetlands are logically becoming more common as wetlands are threatened with climate change and encroachment from development. However, strategic re-wetting, spruce tree removal and moss cultivation can turn these fire hot spots into fire breaks.
Don’t let sparks fly
As fires get worse and fuels abound, there are management strategies to cut to the source and remove the spark. A novel and controversial fire mitigation strategy has been recently practiced in Northern California where an electricity utility pre-emptively cut power to customers in prime fire weather: high winds, low humidity, dry vegetation and heat. Despite pushback from the customers, the utility defended their decision referencing evidence that downed powerlines and weather-damaged electrical equipment have caused major fires in the recent past.
These management strategies are prudent and wise; however, fires always have and always will be part of our vegetated landscape’s lifecycle. Fighting the fires is only one part of the equation; strategies to live with fires are increasingly necessary as the situation in Canada is expected to worsen.
How to live with fires
Take advantage of big data to improve evacuation, management, and planning
As fires are naturally part of an ecosystem, it is climate change and the increasing integration of humans into flammable environments that are making fires into true disasters. Both today and in the future, more people need to be evacuated faster. We have seen this process roll out relatively well, and we have also seen great tragedy. Fires and smoke move quickly, but there is some predictable behavior that can be modeled increasingly well with improving computing power, on-the-ground sensors, high-resolution surveillance and big data. These programs can pull real-time information about topography, ground cover and weather conditions to figure out what is going on and how to respond faster. With this improved information, over time, we should also be able to adjust our designs and infrastructure development to proactively support and improve evacuations.
Change designs and materials
Despite advanced modeling, no matter how quickly we respond, we cannot always mobilize fast enough or make perfect predictions. There are achievable design, construction and regulatory advancements to be made to develop and retrofit buildings for fire-resistant communities (e.g., fire-proof materials, water supplies, multiple exit routes). Roofs are the most vulnerable parts of buildings, so wise design changes might include metal or tiled roofs instead of the more traditional shingles. Further, design modifications and material improvements for vent covers, windows and fences, for example, will contribute small but important strides toward fire-safe dwellings.
Additionally, there is still space for creative thought about how to ‘harden’ communities for fire, protect the structures that we leave behind in a blaze and provide essential services during the recovery period. For example, what role can modular development play in providing temporary shelter and healthcare in the aftermath of a fire?
Filter out the smoke
As demonstrated in the summer of 2018 when smoky hazes from West Coast fires stretched across Canada, the effects of a fire can extend well beyond the burn footprint. We are expecting more smoky summers as fires get worse and seasons get longer.
Like fires, smoke is a threat to health and safety. In 2017, the BC Centre for Disease Control reported an 80 per cent increase in prescriptions for asthma medications. With these new, smokier norms, the public’s consciousness of air quality has risen, and there is a demand for precautions at a larger scale. Last summer, the air quality advisory in BC became the longest on record, and sales of air filtration systems increased nation-wide, up more than 50 per cent in BC and Alberta.
Although naturally ventilated spaces and mixed-mode ventilation schemes are favoured for their positive impacts on saving operational energy consumption, advanced air filtration systems are proving to be important in areas where seasonally poor air quality is becoming common. Ideal future systems will likely aim to minimize negative impacts to both environmental and human health. In the meantime, adapting to smoky summers at a community scale includes retrofitting publicly accessible air-conditioned spaces with sensors and filters to maintain clean indoor air.
Conclusions
There is no doubt that forest fires can be devastating, and we are expecting them to be elevated in intensity, extent and frequency in the future. As climate change drives this trend forward, we are forced to consider how our traditional development adds fuel to the fires, and we are challenged to re-think not only how we physically prevent these fires, but also how we co-exist when they arise.
There is a need to continue advancing our fire-smart management of natural environments and wildland-urban interfaces, evacuations, utilities, building and infrastructure designs and community programming. Fires have always been a threat and with more fires, more people and more development, the threat and opportunities for innovative solutions are on the rise.
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