CO2 from forest fires? Don't worry; it's biogenic carbon and doesn't count.
This is the logic that the Doug Ford government and many Europeans use to justify burning wood for electricity.
In Ontario, where I live, Doug Ford’s government recently announced that they will feed 158,000 tonnes of trees into the Calstock Generating station in Hearst.
“We know that biomass is essential to our forestry industry, and that the industry is essential to Northern Ontario, which is what makes our government’s action plan a win-win for all,” said Minister of Energy Todd Smith. “Securing biomass-fired electricity generation at Calstock Generating Station will continue to promote clean generation, support small communities and secure jobs across the North while maintaining electricity rate stability for families and businesses.”
The government is supporting the development of a 150,000 tonne pellet plant, the feedstock used in power plants like Drax in the UK. According to John Manitowabi, Director of the Department of Lands and Natural Resources, Wiikwemkoong Unceded Territory:
“This plan will support Wiikwemkoong in achieving its goal of the use of forest biomass as a greener solution for local community heating fuel sources and supporting the creation of jobs for the plant itself and the additional forest sector jobs that will be required to move the underutilized and unmerchantable biomass within the Forest Units of Sudbury, Spanish and the Northshore.”
And why is this a greener solution when burning wood releases more carbon dioxide per kWh of power generated than burning coal? Because, according to the IPCC and the International Energy Agency, this CO2 is somehow different. The IEA says.
“Burning fossil fuels releases carbon that has been locked up in the ground for millions of years, while burning biomass emits carbon that is part of the biogenic carbon cycle. In other words, fossil fuel use increases the total amount of carbon in the biosphere-atmosphere system while bioenergy systems operates within this system; biomass combustion simply returns to the atmosphere the carbon that was absorbed as the plants grew.”
They note also that the “IPCC distinguishes between the slow domain of the carbon cycle, where turnover times exceed 10,000 years, and the fast domain (the atmosphere, ocean, vegetation and soil), vegetation and soil carbon have turnover times in the magnitude of 1– 100 and 10– 500 years, respectively. Fossil fuel transfers carbon from the slow domain to the fast domain, while bioenergy systems operate within the fast domain.”
I have never understood this. A CO2 molecule that comes from burning a tree is identical to one that comes from burning coal, and is still going to bash up against the carbon budget that we have to keep under to prevent warming above 1.5 degrees. That means cutting emissions in half by 2030. Burning trees may be fast carbon, but it is not fast enough; it could take forty to sixty years for the tree to grow back and absorb the carbon that was released. As noted in Vox, “Burning biomass means quickly dumping more carbon into the atmosphere at exactly the point we need to begin rapidly drawing it down.”
Sarah Miller wrote about the craziness of this in a New Yorker article in 2021, calling it a “blind spot in the Kyoto Protocol” where burning wood doesn’t count. As David Robertson of Seniors for Climate Action Now! noted in the Star: “Through a series of sleight of hands biomass energy (burning wood) is considered a renewable energy source. Bizarre as it sounds, renewable energy sources are wind, water, solar and burning wood.”
Which brings us back to the forests and the CO2 from wildfires. Studies show that wildfires do contribute to climate change; Steven Davis of University of California, Irvine, said of the 2021 forest fire season: “Boreal forests could be a time bomb of carbon, and the recent increases in wildfire emissions we see make me worry the clock is ticking.”
‘Another way of putting these emissions from 2021 into context is that it is roughly double the emissions in that year from aviation,’ Davis said during a AAAS press briefing. ‘The fires and the emissions are really two decades’ worth of warming and increasingly extreme conditions coming to roost.’ There’s not that much evidence that this record will stand for long, he noted.
And here we are, a year later, and that record is already broken.
Wood that burns in a power plant is no different from wood burning in the forest when counting CO2 emissions. They matter now. That “underutilized and unmerchantable biomass” in the forest might have taken decades to rot and release its CO2 instead of going poof. There is slow carbon (fossil fuels) and fast carbon (rotting trees) and what is essentially instant carbon, what we get from forest fires and burning so-called biomass.
When opposition leader Marit Stiles asked Ontario Premier Doug Ford if he would acknowledge that the climate emergency is making this fire season significantly worse, he responded: “I’m actually in shock that the Leader of the Opposition is politicizing wildfires. It’s staggering, really. But nothing surprises me with the opposition.”
But it is political, and Doug Ford is literally a climate arsonist, throwing logs on the fire and calling it renewable and green. The wildfires demonstrate the folly of this.
I don't disagree with your basic point. But a problem that doesn't get discussed is what to do with the leftover branches, chips, sawdust, etc. that result from turning trees into lumber. I'm not sure it can just be left on the forest floor. And does the leftover stuff increase the fire risk?
Drax imports pellets from the Southeast US made from entire trees, not just the unusable parts. That's truly nuts, from a climate change perspective. But burning just the unusable wood is more complicated. What is the alternative fuel that would be burned to make the power? Is that alternative better or worse than using the wood?
I took a bit of a look into some figures and data involved here.
Roger Pielke writes recently on his Substack that: "wildfire emissions have declined globally since 2003, based on data from the EU." This is good news.
Also, it's good to be careful about using scientists' remarks from journalism, rather than from scientific reports. For instance, I took a look at Steven Davis's (quoted above, from Cal-Irvine) and the other related reports, and they show this:
-Boreal emissions were .48 gtons of carbon in 2021.
-Flight emissions in 2019, before the pandemic, were 1.7 gtons, factoring in a low multiplier for extra climate forcing. If you factor in a larger multiplier, such as the UK uses, then it's double that amount.
This means that Davis was somewhat cherrypicking data for his quote that "boreal fires were double the carbon emissions from flying that year." If you take typical flight emissions for a typical year, then the boreal fires in 2021 were 28% of recent years' flight emissions average. Factoring in the UK's flight emissions climate multiplier (2x), those boreal-fire emissions were only 14% of flight emissions. Then there is the fact that forest fire smoke also has a cooling effect, and not including that in these claims is also a form of obfuscation or a mistake, it would seem.