Does climate change cause wildfires?

IFAW is a global non-profit organisation with the goal of helping animals and people thrive together. For decades, we have done extensive work worldwide to mitigate and adapt to biodiversity loss and the climate crisis.

IFAW is dedicated to making a difference, from collaborating with communities that live closest to wildlife to establishing nature-based solutions across varied ecosystems.

Here, we are looking at the relationship between climate change and wildfires, and how these disasters impact animals and perpetuate the biodiversity crisis.

What are wildfires?

Wildfires are large, uncontrolled fires that spread quickly through wild vegetation and can cause widespread damage to nature, homes, and people. They occur all over the world in forests, grasslands, savannahs, and many other types of ecosystems.

They can begin in a number of ways, both natural and human-induced. One of the most common natural causes of wildfires is lightning—the heat of a single lightning strike can cause a tree’s moisture to evaporate and spark into flame.

Human activities are also significant contributors to wildfires, from lit cigarette butts to campfires left unattended. Another cause is faulty power lines, which can create sparks that ignite nearby vegetation.

When conditions are particularly dry, like during periods of low rainfall, the fire can quickly spread. High temperatures and fast, dry winds can also exacerbate a wildfire. Once a fire starts, it produces heat that dries out nearby vegetation, making it easier for the fire to spread.

The effects of wildfires can be severe. They can destroy forests and wildlife habitats and release smoke and pollutants into the air, affecting air quality and climate. Wildfires also threaten human life, livelihoods, and infrastructure.

The impact of wildfires

Wildfires significantly impact the environment, wildlife, and humans.

Wildfires can:

• Release hazardous air pollutants into the atmosphere, which can cause respiratory problems and other health issues for people living nearby.
• Release large quantities of carbon dioxide and other greenhouse gases, contributing to climate change by increasing the overall levels of these gases in the atmosphere.
• Pollute water supplies, as ash and other fire debris run into and contaminate rivers, lakes, and reservoirs, affecting both drinking water and aquatic life.
• Endanger wildlife by destroying habitats, forcing animals to flee, and sometimes leading to fatalities.
• Lead to soil erosion from a loss of vegetation, which further disrupts ecosystems and makes it harder for plants to regrow.

How does climate change affect wildfires?

There is a proven connection between climate change and wildfires.

Climate change is creating hotter, drier conditions around the globe that increase the frequency, size, and severity of fires. Rising temperatures and changing precipitation patterns contribute to longer fire seasons and more extreme fire behaviour.

Let’s take a closer look at how climate change impacts wildfires.

Increased temperatures

Since 1880, average global temperatures have increased by about 1° Celsius (1.7° Fahrenheit). Though it may not sound like much, this is a massive change in the planet’s climate.

These increased temperatures dry out vegetation and make it more flammable. This means it’s not just easier for fires to start (through natural means or human actions), but they will spread more quickly and burn hotter.

Rainfall and flooding

Climate change is known to alter rainfall patterns and cause heavier than average rainfall and flooding in many places. You might think that increased rainfall is a good thing in areas that experience significant wildfires, but it can actually make wildfires more dangerous. Research has shown that heavier than usual rainfall has led to increased vegetation growth, and with more vegetation, there is more fuel for the fire to burn.

In addition, after wildfires have burned down the vegetation in an area, another surge of heavy rainfall can more easily trigger landslides.

Extended fire seasons

Climate change has not only made our planet warmer but has also made our summers longer. Higher average temperatures and earlier snowmelt prolong the fire season (when most fires tend to occur), giving wildfires more time to ignite and spread.

In fact, severe drought and low humidity have extended the length of fire seasons at a much faster rate than initially predicted by climate models.

On average, the fire season has lengthened by 27% globally and is particularly pronounced in the Amazon, the Mediterranean, and western North America—all places that have been devastated by wildfires in the last five years.

Droughts

Drought and climate change go hand in hand. The increase in temperatures brought on by human actions can be directly linked to the growing number of drought-stricken regions across the globe. Droughts are not just more frequent but also last longer and are more severe.

Long stretches of drought dry out forests and grasslands, creating ideal conditions for wildfires. The dryer a tree or grass is, the more flammable and prone to ignition it becomes.

The period of growth after a drought can also lead to more destructive wildfires. For example, after California experienced an extended drought, it then received abundant rainfall, which led to a rapid increase in vegetation growth. These new plants subsequently dried out during the hot summer months, creating a vast amount of dry fuel, which proved deadly during the wildfire season.

More lightning strikes

As we know, lightning strikes can spark wildfires when they hit dry vegetation. And the occurrence of lightning is increasing.

The warmer the air temperature, the more moisture it can hold. As global temperatures rise as a result of climate change, the air contains more evaporated water. This, in turn, boosts the chance of thunderstorms, leading to more violent storms and more lightning strikes.

Scientists have calculated that for every 1ºC warmer our planet gets, lightning strikes increase by about 12%. This means that if things continue as they are going without intervention, the planet will experience around 50% more strikes by 2100.

Changing weather patterns

Rising global average temperature is associated with widespread changes in weather patterns, which can shift quickly and unpredictably.

Along with higher temperatures, drier conditions, and a longer fire season, altered weather patterns can bring more extreme wind events. Strong winds—especially when they shift and change directions—can cause fires to spread more quickly and unpredictably, making them hard to contain.

Vegetation changes

Climate change has led to shifts in vegetation types growing in certain areas. Warmer temperatures and altered rain patterns can create conditions more conducive to the growth of naturally flammable plants, like dry grasses and shrubs.

As these continue to grow and spread as temperatures rise, the likelihood of wildfires igniting and spreading more rapidly increases.

Pests and diseases

Warmer conditions can also increase the prevalence of pests and diseases that weaken or kill trees, adding dead and dry material that can fuel fires.

Insect outbreaks killed more than 300 million trees in Texas in 2011 and more than 129 million trees in California from 2010 to 2017.

For example, the population of mountain pine beetles has dramatically increased as they spread into areas that were once too cold for them to live. This insect species alone has killed trees across nearly 168,000 square kilometres (65,000 square miles) in British Columbia.

Similarly, after months of dry weather and high temperatures, stressed forest ecosystems have become too weak to fight off infestations of bark beetles. These insects killed around 260,000 square kilometres (100,000 square miles) of trees across North America in 20 years, turning lush forests into acres of kindling for wildfires.

Human activity

Accidental and deliberate human behaviour is also a major contributor to bushfires. While climate change does not directly affect human-caused ignitions, it does increase the amount and size of natural areas that are fire-prone.

A forest that may have been hospitable to campers and campfires 50 years ago may now be so dry and brittle that an errant spark from a contained fire could cause a tree or shrub to go up in flames.

Similarly, a discarded cigarette butt out the window of a car may catch on a patch of grass that has been dry for years thanks to drought, making it much more likely to ignite and spread.

Carbon release

Climate change increases the incidence of wildfires, and wildfires in turn exacerbate climate change—it’s a vicious cycle.

Globally, they add around 5 to 8 billion tonnes of CO2 each year. For context, we emit around 37 billion tonnes of CO2 from fossil fuels and industry yearly.

As fires rage and burn plant matter, carbon dioxide stored in this vegetation is released back into the atmosphere. The increased levels of CO2 further enhance the greenhouse effect, trapping heat in the Earth’s atmosphere and contributing to global warming and climate change over time.

In this way, wildfires perpetuate a continuous and dangerous cycle.

The future of wildfires and climate change

As climate change advances, the future of wildfires is expected to become increasingly dire. Rising global temperatures will continue to dry out vegetation and soil, creating more favourable conditions for wildfires to start and spread.

We’ve already seen it happen: the last decade has seen some of the most deadly fire seasons on record, from Australia to Europe and across the Americas. Even the Arctic faces rising risk of burning due to climate change. There is projected to be a global increase in extreme fires of up to 14% by 2030, 30% by 2050, and 50% by the end of the century. Even if we manage to reduce our greenhouse gas emissions, the United Nations Environment Programme (UNEP) predicts that we could still see increased wildfires worldwide.

That's why finding ways to fight climate change and supporting organisations researching climate change is so important.

At IFAW, we’re actively working every day to combat climate change through our initiatives focused on conservation, wildlife rescue, and habitat restoration. We’re putting nature at the heart of climate action. Our goal is to help communities, landscapes, and wildlife develop resilience in the face of the changing climate—the ability to prepare for, recover from, and adapt to the impacts of climate change.

We understand that healthy wildlife populations and ecosystems are vital for maintaining biodiversity, which contributes to the resilience of natural environments against climate change.

One of our core beliefs in combating climate change is to see animals not just as vulnerable victims of global warming but as allies in the fight for our planet. The animals threatened by climate change can help us tackle it. Animals are essential parts of the global ecosystem and its processes, acting as natural carbon sinks and reducing the amount of CO2 in the atmosphere.

Our planet is in a delicate balance, where everything should work together, but human intervention has upset this functioning.

The natural world is the key to climate resilience. Scientists posit that rewilding natural habitats and ecosystems around the world could reduce CO2 emissions in the atmosphere by billions of tons annually, which is as much as, if not more than, other climate change mitigation measures being implemented.

Through on-the-ground intervention, policymaking, and widespread awareness campaigns, IFAW has made a marked difference in the world of conservation.

With your help and support, we can continue working to fight climate change and address the impact of wildfires.