James Sexton & Derek Soles
Composition and Literature
August 28, 2019
Forestry ranks among British Columbia’s most lucrative industries, generating billions of dollars in export revenue and providing jobs for over 200,000 workers. However, forest fires pose a big threat to the viability of the business; in the past two years, fire has destroyed some 24,000 square kilometres of British Columbia forests. The resulting costs to the province in loss of revenue, purchase and use of expensive equipment, and overtime wages have reached nearly half a billion dollars (Lindsay, 2018). Though lightning strikes and human carelessness continue to be the leading causes of forest fires, global warming has intensified the danger in recent years.
In order to spread, fire needs fuel, oxygen, and heat. Biomass production and vegetative growth provide fuel for forest fires and the photosynthesis of living green organisms creates oxygen (Nix, 2018). When these natural combustibles reach 572ºF, gas in the steam given off reacts with oxygen to reach its flash point with a burst of flame, creating an uncontrolled forest fire.
There are three primary classes of forest fires, depending on the types of fuels involved and their moisture content. Surface fires typically burn readily but at a low intensity; crown fires generally result from intense rising ground fire heat and occur in the higher sections of draping trees; ground fires are the most infrequent type of fire but make for very intense blazes that can potentially destroy all vegetation and organic manner, leaving only bare earth. These largest fires actually create their own winds and weather, increasing the flow of oxygen and “feeding” the fire (Nix, 2018).
Naturally caused forest fires are usually started by dry lightning, where drought accompanies a stormy weather disturbance. Lightning randomly strikes the earth an average of 100 times each second and has caused some of the most notable woodland fire disasters in North America. Because they often occur in isolated locations with limited access, lightning fires burn more acres than human-caused starts (Nix, 2018).
In 2018, between April 1 and August 27, humans were responsible for starting more than 420 of about 1,950 wildfires in British Columbia. Campfires, cigarettes, flares, and car accidents are some of the most common human causes (Smart, 2018). During periods of heightened fire activity, these wildfires divert critical resources away from the naturally caused wildfires that can’t be prevented. The Wildfire Service lumps human activities that spark fires into broad categories, including smoking, electrical, and structure or vehicle fires that spread. About 23 percent of fires started by humans fall under the broad umbrella of “incendiary devices,” which include matches, lighters, flare guns, and others. About 22 per cent spread from campfires. And about the same number begin with open fires, which are larger fires that include burn barrels, pile burning, and large-scale industrial burning (Smart, 2018).
Today, climate change is increasing both the frequency and intensity of wildfires; severe droughts, declining snowpack, more frequent thunderstorms and extreme heat due to rapid warming in the Arctic are all contributing factors. Early in 2018, the World Meteorological Organization noted that the years 2015, 2016, and 2017 were clearly warmer than any year prior to 2015 and, in BC, numerous heat records were broken across the province in July 2018 (Riley, 2018).
Prolonged periods of drought cause forest floors to become lined with dry, dead wood. This combustible material becomes fuel for wildfires and, in hot, dry conditions, a strike of lightning or a carelessly discarded cigarette can be incendiary. Ensuing fires can rip through forests, quickly becoming a dangerous crown fire that burns from treetop to treetop. We can attribute some of these hot, dry conditions to the weakening of the jet stream, the air current that drives weather conditions in the northern hemisphere. The jet stream gets its energy from the temperature difference between Arctic areas and equatorial regions. That temperature difference is getting smaller, so that means our jet stream is getting stagnant and it stalls. A weaker jet stream means hot and dry areas stay that way. The result has obvious implications for wildfires (Riley, 2018).
Adaptation to a new climate-fuelled fire season will prove difficult. Most fire ecologists advocate for prescribed burns, whereby intentionally lit fires burn off the excess fuel in the forest. Letting fires burn may diminish the possibility of catastrophic fires in the future by reducing the amount of fuel built up in the forest. But past forestry-management practices favoured extinguishing wildfires as soon as they started, which has also contributed to increasingly devastating mega-fires. Climate change on top of fire suppression has made the situation much worse. Even if we stopped producing greenhouse gases today, we would continue to warm for the next 50 to 100 years because of the lag in our climate system (Riley, 2018). We are going to continue to warm, so the time to act is now.
Word count: 819
References
Lindsay, B. (2018, August 28). The Future Looks Grim After 2 Years of Devastating B.C. Wildfires. CBC News.
Nix, S. (2018, July 19). The Origin of Wildfires and How They Are Caused. Thoughtco.
Riley, S. J. (2018, August 13). How Climate Change Is Making B.C.’s Wildfire Season Hotter, Longer, Drier. The Narwhal.
Smart, A. (2018, August 27). Humans Responsible for More Than 400 B.C. Wildfires So Far This Season. The Globe and Mail.