Flames from the Donnie Creek wildfire burn along a ridge top north of Fort St. John, British Columbia, Canada, July 2, 2023. /CFP
Editor's note: Liu Zhihua, a special commentator on current affairs for CGTN, is a research fellow at the Institute of Applied Ecology, Chinese Academy of Sciences. The article reflects the author's opinions and not necessarily the views of CGTN.
The 2023 Canadian wildfires have shattered records, surpassing previous fire seasons in terms of severity and extent. The devastating impact of these fires is closely linked to global warming, with climate change exacerbating fire risks. This commentary explores the unprecedented nature of the Canadian wildfires in 2023, their contribution to climate warming through emissions, and the urgent need to address these challenges.
In 2023, Canada experienced the worst wildfire season in recorded history, surpassing the devastating 1989 fire season. According to data from the Canadian Interagency Forest Fire Center, by July 7, 3,519 fires had burned a staggering 8,928,358 hectares. Of the 731 active wildfires, 429 were classified as "out of control." The smoke from these fires has caused air quality alerts, evacuations, and even reached Europe due to global atmospheric circulation.
Contributing factors
Global warming is a significant driver of unprecedented wildfire activity in Canada. Due to climate warming, temperatures have been warmer and drier, raising wildfire risk as vegetation is more flammable under these conditions. In addition, warmer temperatures, coupled with elevated atmospheric carbon dioxide levels, can promote the growth and accumulation of combustible biomass in boreal forests of Canada. This phenomenon, known as the "fuel-limited" concept, leads to denser vegetation and larger fuel loads. Consequently, when a fire ignites, the availability of abundant fuel can contribute to more intense and long-lasting fires, as well as an increased likelihood of fire outbreaks.
Due to climate warming and El Niño this year, a majority of Canadian territory experienced abnormally higher temperatures in early spring 2023, and significantly advanced the fire season in 2023. The fire started in April this year, compared to late May in a normal year.
Forest management is another major driver. Fire suppression disrupts the natural fire regime, allowing fuels, such as dry vegetation and dead organic matter, to accumulate over time. Without periodic low-intensity fires that naturally reduce fuel loads, the buildup of flammable material becomes significant. This accumulation sets the stage for more intense and severe fires when they do occur, as there is an abundance of fuel available to sustain the flames. In addition, Canada replants mostly conifers after forest logging, which has higher flammability than broadleaf trees.
South African firefighters listen during a safety briefing as they prepare to deploy a helicopter in Fox Creek, Alberta, Canada, July 4, 2023. /CFP
Forest fire emissions and climate warming
Forest fires release significant amounts of carbon dioxide (CO2) into the atmosphere, contributing to climate warming. The unprecedented Canadian wildfires have already emitted more than 700 million tons of CO2, surpassing the emissions from Canadian fossil fuel consumption in 2021 and exceeding the emissions of entire countries like Germany.
The release of CO2 from fires exacerbates the greenhouse effect, trapping heat in the atmosphere and further contributing to climate change. The fire emission may hit well above 1 billion tons of CO2, if the current trend continues.
Reducing fire emissions
Historical data shows that since the 21st century, with intensified climate warming and human activities, the scale and frequency of forest fires have been increasing. In recent years, there have been frequent extreme forest fire events, including the 2019 Amazon wildfires, the 2019-2020 Australian bushfires, the 2022 Siberian wildfires, and this year's Canadian wildfires. Therefore, countries must take actions to reduce forest fires and emissions.
One effective measure is to detect and extinguish fires at an early stage. Once the fire spreads and transforms into a crown fire, it becomes challenging to control. Forest fires can be categorized into three types: surface fires, crown fires, and underground fires. Surface fires burn dry leaves, branches, and grass on the forest floor, which are low-intensity fires. Crown fires, with high intensity, can destroy forests and kill most or all of the organisms within them. It's the crown fires that are most destructive and undesirable.
While forest fires are difficult to control, effective measures can be taken to prevent their occurrence. If the combustible materials in the forest are reduced to a certain extent or have high moisture content, it becomes challenging for fires to ignite. Therefore, in fire-prone areas, it is important to control the combustible materials within the forest, remove fuels out of forests, or use them to produce biochar that is less prone to decomposition. This approach can both reduce fires and increase carbon sequestration. In addition, adjusting the composition of tree species in forests can create fire-resistant forest zones and establish natural "green firebreaks."
China's solutions
Despite facing severe challenges from natural and social factors, China has made significant progress in forest and grassland fire prevention. The comprehensive capacity for fire prevention and control has significantly improved, and forest fire incidents in 2021 and 2022 remained at historically low levels.
In May of this year, China issued the "Opinions on Comprehensively Strengthening Forest and Grassland Fire Prevention and Control under New Circumstances," demonstrating the determination of the country to mitigate major forest and grassland fire risks and ensure the safety of people's lives, property, and ecosystems. Now, China's "prevention-oriented, combined prevention and suppression" approach is offering beneficial lessons for the world.
However, under the elevated risk of wildfire, there is need to organize researchers to further study and establish a technical system for forecasting, identifying, and preventing forest fire risks. Additionally, governments should strengthen research on carbon emissions during forest fire processes and establish a more scientific, comprehensive carbon accounting system.
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