People say that wildfires are getting worse. What do they mean exactly?
It means that the number of wildfires is going up and they burn more land for longer period of time. While wildfires are a natural part of our ecosystem, they are getting more frequent and more severe in intensity therefore destructive. This is the case across North America and around the world.
Credit: NASA
What causes wildfires?
Some wildfires happen due to natural causes (lightening being the biggest culprit), and the rest are cause by humans either accidentally or arson. Statistics show that on a global level, only 4% of the fires start naturally and cause distribution varies from region to region. Looking closer at home, in Canada 55% are started by lightning whereas 84% are started by humans in the US (Dunne, 2020).
What’s the relationship between climate change and wildfires?
Risk factors contributing to wildfires include temperature, soil moisture, lightning strikes, wind, and the presence of fuel (trees, shrubs, and other types). Climate change has a tie to all of these factors. For example, climate change is known to enhance the drying of organic matter in forests (these are the same material that burn and spread wildfire). When vegetation on land is drying it creates “tinderbox conditions”. It means if sparked, a fire can spread very quickly, over large land mass. Also, as a result of global warming, winter snowpacks are melting about a month earlier. This means that the forests are drier for longer periods of time. There are other domino effects at play as well. An example of how climate change indirectly promotes forest fires is through warming temperature resulting in unprecedented spread of mountain pine beetle. The beetles kill trees which in turn increase wildfire fuel. This is a serious issue in BC and Alberta.
What’s the severity of the damage?
The damage is wide reaching, everything from the devastating loss of human and animal lives, depletion of forests and habitat, shelters and possessions, to the trauma it causes to its victims. Wildfires are costly in every sense of the word. In 2016, the Fort McMurray fire came with a $10 billion bill (Natural Resources Canada). The total costs of wildfires in 2017 and 2018 were estimated to be over $40 billion in the U.S. alone (NOAA).
What is the Climate Feedback Loop?
Wildfires are a main driver of greenhouse gas emissions. Increased greenhouse gas emissions result in extreme temperatures which create dry conditions that are fire-prone. Increased fires around the global in turn bring about even more emissions and the cycle continues.
What Can Be Done?
Reducing global emissions to combat climate change is key. In terms of mitigation and risk reduction, there are adaptive measures communities can implement to reduce fire risk. This includes removing built-up forest litter, regulating fuel-rich private land, incorporate fire safety in building design (such as avoiding use of flammable materials in construction and landscaping). Land management is vital and includes prescribed burning (or controlled burning). These burnings are low-intensity and they remove underbrush, debris and fallen timber. This helps reduce the risk of massive wildfire but know that they not a perfect solution as they come with the risk of becoming a damaging wildfire as well as contributing to poor air quality and greenhouse gas emission.
