Carbon footprint of a forest product: challenges of including biogenic carbon and carbon sequestration in the calculations

Discussion about the impacts and consequences of climate change has aroused interest in the carbon emissions that are associated with the purchased products. In the methodology development, the inclusion of biogenic carbon has turned out to be problematic. The problems with including biomass carbon are mainly related to forest carbon balance and some methodological issues concerning carbon storage in products. There are several open questions that have to be solved, such as the time frame used in the carbon footprint calculations. Before a generally accepted methodology is available, several varying approaches are applied, depending on who is performing the calculations and what their goal and scope are. The effect of wood raw material harvesting on the forest carbon balance can be calculated in various ways. Three different approaches are presented in this paper. In the first approach, it is claimed that sustainable forest management ensures that the same amount of carbon taken out from the forest is absorbed again by the forest growth. The opposite way is to calculate the lost carbon stock and allocate it to products. The third approach allocates the net carbon sequestration through net forest growth to forest products. Guidance concerning carbon storage in products exist and they are discussed in this paper. The challenges of including the forest carbon balance are expressed with the case calculation examples.