How climate change is fueling forest fires across the world

Forests are a vital part of our ecosystem. As well as being habitats for the majority of the worlds flora and fauna, the existence of established forests protects against floods, droughts, landslides and other extreme events. 

Forests are also an important system for climate change mitigation as they act as carbon sinks,  balancing levels of oxygen, carbon dioxide and humidity, as well as protecting watersheds, which supply 75% of freshwater worldwide.

But a worrying acceleration in forest loss has been reported, with 2020 being the third-worst year since comparable monitoring began 20 years ago. A large part of the losses have been in the Amazon, the Congo and Southeast Asia but there has also been a substantial increase in loss in America, Australia, Europe and even Alaska over the last year. 

And whilst some of the loss is linked to human deforestation, though activities such as logging or clearing land for agricultural purposes, other causes are heavily associated with climate change. One such association are wildfires.

Although wildfires occur naturally as part of the ecological sequence, they are increasing in frequency and intensity, and are harder to fight, due to the conditions created by climate change. 

Longer and hotter dry spells create ideal environments for fires to start and spread at a rate that is difficult to keep under control. A reduction in humidity dries out the vegetation, such as grasses which ignite easily, and kills off trees which provide more fuel for the fires. 

Increased nighttime temperatures also mean that fires burn for longer whereas previously cooler nighttime temperatures may have weakened or extinguished fires after a day.

As the atmosphere warms, the amount of moisture in the air decreases the propensity for extreme fire behaviour increases. We are seeing shifts in rainfall patterns and increased temperatures result in decreased levels of snowpack which would normally melt over a longer period of time.

On the west coast of America, one report found, the fire season is now 75 days longer than in the 1970s. In fact, last year California saw the number of wildfires double with more than 8,200 fires devastating an estimated 4 million acres

The cause of the fires varies. The California fires last year were mostly caused by a series of lightning strikes. But fires are also sparked by other means, for example, one of the largest fires in 2018 was started by sparks flying from hammering a concrete stake into the ground in 100-degree Fahrenheit heat. A second was caused by sparks from a car’s tire rim scraping against the asphalt after a flat tire. 

Australia has seen a ninefold increase in the loss of tree cover over the past two years, largely due to extreme weather and forest fires. Having battled bushfires and droughts throughout 2020, parts of the country is now experiencing extreme flooding. Water levels have been rising so quickly that thousands of people have been evacuated from their homes. This exceeds anything that has occurred in the past 50-60 years.

Even the United Kingdom, whose main threat from climate change is typically understood to be increased flooding, is now at riskof more severe wildfires. Over the last few years, large fires have swept across expanses of the country and it is predicted that this will increase if carbon emissions are not contained globally. 

Juxtaposed environmental events such as fires and floods have magnified impacts on ecosystems. The wildfires devastate the vegetation, leaving it unable to respond to floods occurring a few months later which leads to more flooding and destroys further vegetation.

And with more fire comes more emissions. Increased global emissions lead to higher temperatures, which then create drier, more fire-prone conditions perpetuating the entire cycle creating what the World Research Institute calls the Climate Feedback Loop

Fires and the climate feedback loop.

(source: https://www.wri.org/blog/2020/us-fires-climate-emissions ) 

The effect of large scale fires also has a significant human impact that extends beyond the immediate loss of life and property. Smoke inhalation has serious health implications and long-term exposure has been linked to higher rates of respiratory and heart problems. Both air and water quality can be affected for people thousands of miles from the source of the original fire.

Furthermore, the United Nations estimates around 1.6 billion people, including more than 2,000 indigenous communities, depend heavily upon forests for their livelihood. They also act as a safety net for some communities, for example, in times of food shortages and provide opportunities for sustainable, renewable farming practices. 

Keeping existing forests standing, particularly in tropical regions, and restoring wooded areas that have been damaged, has long been recognised as one of the cheapest ways of tackling the climate crisis. 

In 2014, the New York Declaration on Forests was signed at the UN in which countries were required to halve deforestation by 2020 and restore 150m hectares of deforested or degraded forest land. Despite this, the rate of loss has gone up by 43% since 2014 and continues at an alarmingly fast rate.

Some countries are making progress. Deforestation is decreasing in Indonesia and Malaysia with governments there making logging illegal and implementing tougher laws such as restricting palm oil plantations, for example.

Ethiopia, Mexico and El Salvador are also embarking upon tree planting schemes. But there is a long way to go to replace the huge amount of forests that have already been destroyed. 

Extreme weather events themselves are not caused by climate change, but they are coming much more frequently and much more intensely because of the effects of climate change. 

With COP26 just around the corner, record-breaking events that we have seen across the globe over the last 12 months should serve as a call to action to world leaders to address the climate feedbacks that are causing them. 

“Forests need to be on the agenda for COP26. The world’s forests are still an enormous carbon sink, and we need to keep that carbon sequestered to avert catastrophic climate change.” (Frances Seymour, WRI)