Are wildfires getting worse because of climate change? | Ask a Scientist

Wildfires have been big news recently, but why, and are they connected to climate change? Research scientist, Megan Kirchmeier-Young, joins us to answer these questions.

If you want to dig deeper into Megan’s research, check out Human influence on the climate increased the likelihood of the record-setting area burned across Canada in 2023 in Nature’s npj Climate and Atmospheric Science Journal.

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ON SCREEN:
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ON SCREEN:
Kalina Parisien, Host, Ask a Scientist, Environment and Climate Change Canada

KALINA PARISIEN:
Hello and welcome back to Ask a Scientist. Wildfires have been making headlines more and more and are causing a lot of concern. Today we have a question looking at a connection between climate change and wildfires.

MARIO PALUMBO:
Are wildfires getting worse because of climate change?

KALINA PARISIEN:
Luckily, we have with us today an expert on climate change, Megan Kirchmeier-Young. Take it away Megan.

ON SCREEN:
Megan Kirchmeier-Young, Research Scientist, Environment and Climate Change Canada

MEGAN KIRCHMEIER-YOUNG:
We know that human-caused climate change is leading to an increased risk of extreme fire conditions.
The main reason is that temperatures are increasing, and summer heat extremes are also becoming more frequent and intense.
Scientists at Environment and Climate Change Canada have identified the ways that temperature changes can impact fire risk.
First, increasing temperatures can lead to enhanced fire weather. Fire weather is weather conditions, such as hot, dry, and windy, that are favorable for fires, affecting their occurrence and subsequent behavior. Increasing temperatures lead to more days with the right weather conditions for fires to ignite and spread. Especially when combined with low precipitation, hotter temperatures can lead to more extreme fire weather.
There is also a prolonged period where heat extremes occur, starting earlier in the year and ending later in the year, resulting in a longer fire season.
We also need to consider changes occurring in other seasons and variables. For example, we know that snow melt is occurring earlier in the spring across Canada. This means that the moisture from snow melt is lost through processes like evaporation and river runoff earlier in the season. Resulting in a drier landscape that also enhances fire risk. An earlier loss of snow also contributes to an earlier start to the fire season.
All together, enhanced fire weather, with a greater possibility of the right weather conditions for fires to ignite and spread, and a longer fire season, are the result of increasing temperatures driven by human-caused climate change.

KALINA PARISIEN:
Thank you Megan for helping us understand the impacts of climate change and wildfires.

Keep being curious! I’ll see you again on the next episode of, Ask a Scientist.

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