The Climate Crisis is Causing Wildfires Globally

Jennifer McDowall explains how global warming is causing wildfires to last longer and burn more intensely.

Photo by Alfred Kenneally

Rising temperatures are causing droughts and early thaws, which in turn result in drier soil and vegetation, which are more likely to burn. Other weather factors such as humidity, length of intervals without rain and wind speed can also increase not only the likelihood of igniting a fire, but the length of a wildfire season and how large an area will burn.

In 2020, one of the hottest years on record, over four million acres (16,187km2) of land burned in California; across the world each year, an average of 3.5 million km2 is destroyed by wildfires. In recent years, the US States Oregon and California, as well as the Arctic Circle, have been particularly affected; and in Australia, climate change has increased the likelihood of fires by 30%.

A study published in 2020 showed that in California, the amount of autumn days with ‘fire weather’ are twice as frequent now than they were in the 1980’s. Fire weather days exhibit increased temperatures together with decreased precipitation and have been shown to coincide with extreme fire events. As global warming continues to increase, so too will the number of fire weather days in these vulnerable areas, unless carbon emissions can be reduced and climate change slowed.

To make matters worse, the Santa Ana winds that fan the flames of Californian wildfires are set to become even drier by 2050. As around half of the increase observed in the total area affected by forest fire since the 1980’s is a result of the increased drying of fuel, this will most likely exacerbate the problem.

An increase in weather conditions conducive to wildfires means seasons are now 53% more likely to be longer than average, and the areas experiencing longer seasons has increased by 108% since 1979. Seasons in 2013 were estimated to be 19% longer longer than those in 1979 for more than a quarter of the earths vegetated surface. In South America, for example, seasons are now on average 33 days longer than in 1979.

The wildfires themselves also produce significant amounts of greenhouse gas, thereby contributing further to climate change. The amount of CO2 released can reach more than half the emissions produced from the use of fossil fuels each year. As our climate continues to change and become drier, conditions amenable to wildfires will increase. The longer seasons observed in recent years are also reducing the ability of the soil to absorb carbon and further increasing the carbon released into the atmosphere.

Although wildfires can occur naturally, ignited by lightning or lava, the majority are started by people. In the US alone, up to 90% of wildfires are ignited by humans; this includes accidents, arson and controlled or prescribed burns.

Prescribed burns are positive ways to manage forests and grasslands: areas are burned in a safe manner so that the amount of fuel available to burn uncontrollably is reduced. The benefits of smaller natural wildfires, such as an improvement in soil fertility and an increase in resistance to both drought and fire, can be achieved by controlled burns. Many areas perform fire suppression, i.e. putting a fire out as soon as it starts, due to the increasing number of housing developments in the fire-prone Wildland Urban Interface (WUI), or the area between unoccupied wild land and built-up areas.

Although fire suppression sounds like a good thing, it actually contributes to the severity of larger wildfires as it results in an accumulation of dry fuel. Practising controlled burns helps get rid of flammable debris and reduces fuel for future fires. Although more housing on the WUI and fire suppression increase the risk and severity of wildfires, these changes are not enough to account for the increase in wildfires seen today.

Nevertheless, while fire management can play a role in reducing the occurrence and severity of wildfires, it is global warming that really needs to be addressed. Fighting climate change and reducing wildfires could prevent numerous deaths, poor air quality-related health issues, homelessness resulting from damage or loss of property, and interruption to both business and education due to closures of public infrastructure – in addition to the deaths of billions of animals.

Article on a similar topic: Australia: Wildfire Blazes Through Fraser Island Heritage Site

We are a not for profit socio-ethical impact initiative advocating for topics that matter, whilst supporting wider planetary change and acknowledgement. Support our journalism by considering becoming an advocate from just £2.