How much are forest fires in themselves driving climate change? And how should firefighting resources be best spent from a CO2 perspective?

To what degree do large forest fires contribute to net CO2 output in the atmosphere? As forest fires are getting more and more severe; should communities put their increasing climate budgets into better prevention methods - or into more and larger extinguishing power? 

By CTIF staff writer and information manager Björn Ulfsson

Recently, several climate studies concluded that many Canadian forests are currently putting out more CO2 than they absorb.

The  CBC News claimed in 2021 that Canada´s managed forests have not in reality been a net carbon sink since 2001, calling for more protection of old growth forests as a way to better carbon trap. As the article stated, forested northern countries like Canada, the US, Russia and Scandinavia can perhaps no longer lean back and rest their climate efforts in the idea that their forests are absorbing  - and thereby offsetting - a large part of the their total CO2-output into the atmosphere.

For when all factors, like bug infestations and  forest fires, which are more common in working forest farms than in old growth forests, have been taken into account, more CO2 is allegedly being released from the dead wood, than what the living wood can absorb. 

"When you add up both the absorption and emission, Canada's forests haven't been a net carbon sink since 2001. Due largely to forest fires and insect infestations, the trees have actually added to our country's greenhouse gas emissions for each of the past 15 years on record", CBD writer Robert Fletcher writes in his February 2019 article.  

The CBC article also references another study, showing that the forests in the province of British Columbia contribute carbon emissions at levels previously unknown to scientific research: The article references claims by the Sierra Club which estimates that B.C. forests absorbed about 28 million tonnes of carbon dioxide in 2016. However,  the group's report says B.C.'s forests started emitting more carbon than that since the early 2000s.

"The emissions result from logging practices such as clear-cutting of old-growth forests and slash burning, as well as the increasing impact of climate change including pine-beetle outbreaks and wildfires", the report says.

While this may be true for Western Canada, at the same time, environmental studies also show that globally, regrowth of new trees in logged areas are also absorbing a significant part of the CO2  released during and after a wildfire. The same is true overall for areas which are logged: when a clear cut area is re-planted, and re-seeded properly, re-growth of trees generally absorbs a large percentage of the CO2 released when the mature trees were harvested.

Therefore, the exact number of how much forest fires are driving climate change is close to impossible to calculate.

So how then, can structural planners decide if they should spend more money on firefighting resources or on other mitigations? - Especially if the effect on climate change from fires cannot be measured?

While an exact number is hard to find,  there are some reasonable estimations on how much forest fires affect the climate on average.  The environmental site Inside Climate News claimed in a 2018 article that the scientific estimate is  "... wildfires make up 5 to 10 percent of annual global CO2 emissions each year".

The same article compared global total output of CO2 in to the atmosphere (from all sources) with the gross output of CO2  from wildfires in 2018. Those unedited number (not considering re-growth re-uptake) are staggering: Forest fires made up close to 25 % of all CO2 production in 2018.

In plain numbers: 8 billion tons of CO came from forest fires, compared to the total output of 32 billion tons of CO2 d(form all sources) during the same year. 

So should more resources be put into fighting forest fires from a climate perspective alone? Or is the budget  ´earmarked´ for climate work better spent elsewhere? That question is - likely - equally difficult to answer.

While forest fires are part of the natural carbon cycle and have always existed since long before humans even existed, recent forest fires are becoming bigger and more prolonged. The reasons for this are as complex as they are interconnected. 

While many argue for spending more money on fighting forest fires through traditional suppression techniques, a quick look through tactical outcomes of  recent large forest fires will likely show that no amount of existing technology or fire fighting tactics could do more than at best limit the spread.

In more or or less in every case when a forest fire reaches a certain size  only rain can stop it, or at least a change in weather pattern, such as the end of a prolonged heat wave, or a change in persistent windy conditions (which often turn wildfires into wind driven fires.)

As the US Wilderness Society states  in a 2019 article, it is reportedly not just climate change which is driving these large fires to get worse each year. Other human activities - which perhaps are easier and quicker to remedy than our global energy consumption - also drive forest fires to a significant degree: 

1. Development of new construction near forests and grasslands.

Quoting the article:  "... the areas where communities encroach on forest and grasslands are the places where fire is most likely to kill people and destroy homes and businesses. One of the most basic and important changes we could make would be to check runaway development in such areas and leave the wildest places more or less wild". 

2. Changing commercial forest practices:

Slash Burning, removal of dead wood and planting Fire Resistant Trees

Deliberately burning off underbrush in a method called Slash Burning  (also called  `Backfire` or `Prescribed Burns`) is a controversial practice where forest fires are either allowed to run their natural course, or (more commonly) when fires are deliberately started (by fire services or others with the means to control the burn) during "safe" times of the year when the risk of uncontrolled spread is deemed low.

CTIF.org has previously described the process of Back Burning, or Slash Burning, in an article originally published by the american NFPA.   

The practice of Prescribed Burns tries to mimic natural wildfires from before human civilization.Some also claims  the methods resemble the practices native aboriginals in North America reportedly used before the arrival of modern european immigrants.  

However, as another CTIF.org article points out; climate change itself is making slash burning as a practice more and more controversial, as the increased severity of both weather related events, especially droughts, continually keep making the practice harder and harder to perform safely for many practitioners.  

Those critical of the method often claim that the practice nowadays is not compatible to when the climate was different and when forest fires were generally smaller due to a larger diversity of tree species in the forests. However, cultivating bio diversity in the forests for fire prevention purposes is another method claimed by many as the "holy grail" of forest fire prevention. 

As CTIF.org has previously reported, recent Western Canadian research has claimed that studies show potential  fire safety benefits (and overall economic savings) could be achieved if forestry companies started planning both their logging and reseeding practices with consideration to leaving certain types of fire resistant tree types as "fire stoppers" between sections in working forests.

One of the tree species hailed as a solution to forest fire spread is Aspen trees, as described in this article from  2019 on CTIF.org:   

"Aspen trees and birch naturally flourish after a wildfire, but they're also less vulnerable to flames than coniferous trees", according to the research material referenced in the article.  

In an article from 2018, Bethany Lindsay, at CBC News, looked into various studies showing how modern forestry practices, rather than climate change alone, may be to blame for the recent ´wildfire epidemic´ in North America and around the world."

Another - slightly less controversial but still somewhat problematic - method of fire prevention is mechanically removing dead wood from the forests as a means to lessen the amount of dry, flammable fuel which can allow for a spark from a train or a a run away campfire to get out hand. 

In another article on CTIF.org, we reported on what the left wing NDP writer Bill Tieleman wrote for the TheTyee.ca: He outright blamed the British Columbia provincial government for the 2017 fire season, by neglecting to live up to its goals to remove debris from the forests.

According to Tielemen and many others, leaving dead wood in the forests could be the true reason for why Western Canada experienced such a deadly fire season that year - rather than (just) climate change:

“While the cost of fuel management may seem expensive, research has shown that, in general, hazard mitigation investments cost less than wildfires when all direct, indirect and additional costs of wildfire are tallied", Tieleman writes in the article.  

Significant government investments into ecological fire prevention

While adaptations to more "fire resistant" forestry practices may seem slow in many areas of the world, there are also significant investment being made in many high risk areas.

As CTIF.org reported on in 2018, the US Department of Agriculture, invested nearly 32 million USD that year to mitigate wildfire risk. As the article pointed out, the investments were primarily concerned around restoring sections of especially vulnerable forest to a more natural  state.

However, as complex as interconnected as forest fire fighting is with forest management and societal planning; environmental protection legislation and ecological studies on how to best manage logging and re-planting, is just complex. 

Not all dead wood can - or should always - be removed

While removing dead wood from forests may seem like the obvious (yet labour extensive) answer, removing dead wood can also have unwanted environmental impacts.  

Ellen Mcdonald, an ecologist at the University of Alberta, points out in a 2019 study that the leftover branches from forest harvesters and other logging is the biggest problem for the spread of wildfires, rather than dead trees and large branches infected by bugs like the pine beetle - or even than trees which have been partly burned by fire:

"Contrary to what many believe, large dead trees are not a major fire hazard and the finer materials left behind after logging, like branches, are a bigger risk.... It's fine materials that will carry a fire. When you want to start a fire, you don't put this big log in your fire pit, it has to start with smaller pieces. It's the same in the forest, so dead standing trees aren't that big of an issue."

Prevention or extinguishing?

So back to the original question: How much are forest fires affecting climate change, and to what degree should communities put their increasing climate budgets be put into better prevention methods or into more extinguishing power? 

Of course that question will be answered differently from community to community, and cannot be answered as a blanket statement which covers every situation of planning. However, the answer may be closer than we think, with more and more scientific research resources being funneled into finding the answer. 

As KQED.org states in a recent 2021 article: While last year´s fire season was terrifying, the summer and fall of 2022 will likely be even hotter, leading to an even higher risk of severe wildfires. 

Leila Carvalho, a UC Santa Barbara professor of meteorology and climatology, says in the article long-term climate trends—like heat waves drying out vegetation early in the year or drier springs—will continue throughout 2022.  

But Carvalho is also hopeful, at least for the state of California, for two important reasons: dead wood removal at an unprecendented  scale, and new world wide scientific research into the effectiveness extinguishing methods and prevention tactics.

"First, the state (of California) has set aside more than a billion dollars to strategically remove brush and trees to rescue catastrophic wildfires. Second, so many scientists are studying the effects climate change and historic fire suppression has on drying wildland areas... People are trying to find solutions to mitigate and adapt because we have to deal with these swinging extremes in climate... therefore  I'm hopeful that we are perhaps dealing with problems in ways we haven’t been doing before”, Carvalho says.

Photo Credit: (Cover Photo Above) Public Domain Photo from the US National Archives

Title: Firefighters in Colorado

Production Date: 01/08/2009

Photographer Name: Michael Rieger

City/State: Boulder, CO