How is climate change impacting forest fires in Canada?

Canada Wildfires

The conditions that favour the spread of wildfires, increased temperatures and frequent droughts, are two of the biggest symptoms of climate change. Consistent with the effects of our changing climate, many studies have shown that area burned by wildfires has been increasing over the last four decades, despite improvements in fire suppression techniques.

Studies also predict that the area burned in Canada will double by the end of the century. Natural Resources Canada indicates that the average area of forests burned over the last 25 years has been 2.3 million hectares a year. As of September 2nd, 2015, the area burned in Canada this year is almost 4 million hectares.

According to Natural Resources Canada, sustainable forest management practices have kept the deforestation rate in Canada at virtually zero (0.02% per year) over the last two decades, but that deforestation rate does not include tree losses due to harvesting, forest fires, or insect infestations. That’s because the trees lost under these circumstances should all grow back naturally. But, what happens when some of the forces driving tree losses are on an upward trend?

If the devastation experienced in Western Canada and the US this summer is an indication, forest fires and climate change are topics that need to be included in a discussion about deforestation.

Forest fires are strongly influenced by four factors: weather/climate, fuels, ignition agents, and human activities. Over 85% of the time, it’s a strike of lighting that acts as the ignition agent. The main factor influencing lightning’s ability to start a fire is temperature, with warmer temperatures leading to more fires. As one might expect, dryer fuel also encourage wildfires to grow.

A region experiencing particularly warm and dry conditions is said to be having extreme fire weather and it only takes a small number of extreme fire weather days to cause a tremendous amount of damage.

In fact, each year in Canada, 97% of the total area burned is caused by just 3% of the fires.

As our climate changes, the number of days with extreme fire weather potential is on the rise.

When talking about forest fires, it is important to keep in mind that wildland fires are completely natural and play an important role in maintaining the health and diversity of the forests. On the other hand, fires that get out of control threaten our communities and destroy vast amounts of commercially viable timber. It’s also very costly to suppress fires. Over the last decade, fire suppression has cost Canada between $500 million and $1 billion each year.