‘Link between climate change and wildfires’
8th Oct, 2020
While wildfires are typical in both California and parts of Australia in the summer months,
While wildfires are typical in both California and parts of Australia in the summer months, the intensity and scale of wildfires that these areas have seen in recent years has raised some concerns among scientists about the linkages between human-induced climate change and fire risk.
- In an updated review of scientific articles that try to establish a link between climate change and fire risk published since January 2020, scientists note that human-induced climate change promotes the conditions on which wildfires depend, enhancing their likelihood and challenging suppression efforts.
- The update focuses on the ongoing wildfires in the western US and the bushfires that ravaged southeastern Australia in 2019-2020.
- Further, the authors note that climate change increases the frequency and severity of fire weather around the world and that land management alone “cannot explain recent increases in wildfire because increased fire weather from climate change amplifies fire risk where fuels remain available”.
Factors that can influence fire weather
- The Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), which was published in 2013, identified a few factors that could influence the way wildfires play out. These include-
- global increase in average temperatures
- global increases in the frequency, intensity and extent of heatwaves (breaching of historically extreme temperature thresholds)
- regional increases in the frequency, duration and intensity of droughts
Understanding from new trends of forest fire
- Scientists are wary of attributing any single contemporary event to climate change, mainly because of the difficulty in completely ruling out the possibility of the event having been caused by some other reason, or a result of natural variability.
- However, new analysis shows that natural variability is superimposed on the increasingly warm and dry conditions that have resulted from climate change, which has led to more extreme fires and more extreme fire seasons.
- Further, there is an “unequivocal and pervasive role of climate change in increasing the intensity and length in which fire weather occurs”.
- While land management is also likely to contribute to the wildfires, it does not alone account for the recent increases in the extent and severity of the wildfires in the western US and in southeast Australia.
Forest fire in Australia
- While bushfires are routine in Australia in the summer months, the scale and intensity of the fires last year was unprecedented.
- The fires killed thousands of animals and impacted more than 10 million hectares of forest land, which is an area the size of South Korea.
- Scientists suggested at the time that there was strong evidence to suggest that the bushfires, which were especially fierce last year, could be linked to climate change.
Why Forest Fires Are Both Necessary and Dangerous?
The Ecological Benefits of Wildfires
- Promote ecological health: Humans have been performing such burns for thousands of years and for multiple reasons, but, today, they are mainly used to promote ecological health and prevent larger, more damaging, uncontrolled fires.
- Bring survival and production: Fire is a natural phenomenon, and nature has evolved with its presence. Many ecosystems benefit from periodic fires, because they clear out dead organic material—and some plant and animal populations require the benefits fire brings to survive and reproduce.
- Increase in soil fertility: When humans perform a prescribed burn, the goal is to remove that layer of decay in a controlled manner, allowing the other, healthy parts of the ecosystem to thrive.
- Moreover, nutrients released from the burned material, which includes dead plants and animals, return more quickly into the soil than if they had slowly decayed over time.
- In this way, fire increases soil fertility—a benefit that has been exploited by farmers for centuries.
- Essential for life cycle: Several plants actually require fire to move along their life cycles. Even some animals depend on fire.
Harmful Effects of Wildfires
- Long term effect on nature: Wildfires can have immediate and long term effects on the quality of rivers, lakes, and streams.
- Prevent absorption of water: The most noticeable impact of wildfires is storm water runoff. After the loss of vegetation, the ground’s soil becomes hydrophobic and prevents the absorption of water.
- This inability to absorb water promotes the transportation of debris and sediment into larger bodies of water, further polluting valuable and essential resources.
- Post-fire flash floods: Post-fire flash floods become a threat and allow the introduction of heavy metals from ash and soil to infiltrate waterways. Filtering these water sources can be costly as well as time consuming.
- A threat to survival: The flames from these fires destroy the food source and homes of many animals, threatening their survival. For plants and trees that can survive the flames, they are susceptible to disease, fungus, and insects due to their decreased resistance following burn injuries.
- Impact on air quality: Wildfires have both immediate and long-term impacts on air quality. As a forest burns, large amounts of smoke are released into the atmosphere. These smoke particles are typically small and made up of gases and water vapor.
- A threat to human health: Air pollution from fires has the potential to travel great distances and oftentimes may pose a threat to human health. These small particles can become lodged deep within lungs, making it difficult to breath as well as placing additional stress on our hearts.
There are many ecological benefits of forest fire but, the present day forest fires are a big issue in many parts of the world. The human-induced climate change has promoted the conditions on which wildfires depends. Hence, regulating bodies need to be vigilant and preemptive with forest fires, in order to help curb their frequency. Further, Regional think-tanks and governing bodies can help create a strategy for at-risk areas where each local population and fire prevention and suppression group can be involved.