Jari Niemi and Sampo Soimakallio: Less is more: Why lowering the demand for natural resources is good for climate
Reaching the climate goals set in the Paris agreement requires that three mitigation measures are applied simultaneously: 1) deep cuts in fossil-based CO2 emissions, 2) maintaining and strengthening the land carbon storage and sink 3) scaling up of permanent CO2 removals from the atmosphere i.e., geological storage of carbon. Changes in wood use may in principle contribute to all these three measures, but not at the same time due to inherent trade-offs.
To quantify the effects of increased wood use on CO2 balances, we need a reference scenario, “the world without the increased wood use”. Compared to this reference scenario, increased wood use reduces the amount of carbon stored and sequestered in forests. This reduction can be considered as a forest carbon debit (or debt). On the other hand, there can be benefits. Increased wood use may result in reduced fossil emissions and more carbon in harvested wood products and geological storage. These benefits can be considered as technosphere carbon credits.
To mitigate climate change, technosphere carbon credits should be higher than forest carbon debits.
To mitigate climate change, technosphere carbon credits should be higher than forest carbon debits.
Unfortunately, our studies show that technosphere carbon credits are likely far too low to compensate forest carbon debits within this century, a timeframe critical to stabilize the global temperature increase to well-below 2 degrees. Simplified: one additional unit of carbon harvested from forests provides approximately 0.5 units of technosphere carbon credits but reduces forest carbon stocks by around 1.6 units – the net effect being climate warming. According to our studies, this is exactly what happens at least in a 100-year timeframe. Even though the results are affected by several assumptions, none of these underlying uncertainties changed the big picture. Technosphere carbon credits can’t compensate forest carbon debits.
Decarbonization of societies increases challenges for using wood in climate change mitigation. This is because technosphere carbon credits decline over time rather quickly along with decarbonization of energy and material production, which prolongs the payback time of forest carbon debts. However, directing the use of wood from short- to long-lived products and to permanent storage would enhance its climate mitigation potential by extending carbon retention times.
Our studies show that increased wood use does not help to reach climate goals within this century, which begs the question of whether the use of wood should rather be reduced.
Our studies show that increased wood use does not help to reach climate goals within this century, which begs the question of whether the use of wood should rather be reduced. From the perspective of reaching these climate targets, the answer is yes. Reducing wood use would also slow down the loss of biodiversity in the forests and reduce erosion and nutrient leaching.
The dilemma is that reduced wood use should not lead to increased CO2 emissions from fossil fuels, and on the other hand, decreasing the use of fossil fuels should not lead to reduce the amount of carbon stored in forests. To avoid these risks, appropriate and well-designed climate policies are required to ensure simultaneous reduction in fossil-based CO2 emissions, increase in permanent removals of CO2 and increase and maintain of land carbon storage and sink.
About the authors:
The authors Jari Niemi and Sampo Soimakallio participated in the Sustainable and multifunctional use of forest biomass project, funded by a European network of public funding organisations (ForestValue2). Jari works as a researcher and Sampo as a development manager at the Finnish Environment Institute's Climate Solutions unit.
More about the topic in articles published in GCB Bioenergy Journal by the authors:
- Jari Niemi, Sampo Soimakallio, Elias Hurmekoski, Tanja Myllyviita, Janni Kunttu, Federico Lingua, Tord Snäll: Carbon Credits Through Wood Use: Revisiting the Maximum Potential and Sensitivity to Key Assumptions (onlinelibrary.wiley.com)
- Sampo Soimakallio, Hannes Böttcher, Jari Niemi, Fredric Mosley, Sara Turunen, Klaus Josef Hennenberg, Judith Reise, Horst Fehrenbach: Closing an open balance: The impact of increased tree harvest on forest carbon (onlinelibrary.wiley.com)
