Understanding the benefits and challenges of harvested wood products in response to climate change

The greenhouse gas emission reduction potential of harvested wood products (HWPs) is widely recognized and future demand is expected to increase. However, inconsistencies in system boundaries, time horizons, and scenario assumptions in life cycle assessment (LCA) have led to distorted climate impact assessments and misguided policy formulation. To address this, we propose a comprehensive framework covering life cycle, temporal, and spatial dimensions to assist in considering comprehensive factors in evaluating HWPs climate impacts using LCA. Our review of existing studies highlights the significant climate mitigation potential of long-lived HWPs used in construction and furniture, while short-lived products such as bioenergy and paper exhibit uncertainties and can contribute to net emissions. Existing analyses often overlook factors such as indirect land use change emissions, substitution credits, as well as emissions and storage in the end-of-life stage. Moreover, there are misconceptions regarding the selection of time horizons and characterization of climate impacts, as well as emission leakage caused by international trade. Utilizing HWPs for climate mitigation faces challenges such as forest biomass shortages, substitution benefits leakage, and trade-offs between forest protection and utilization, long-term versus short-term goals, and regional versus global benefits. Additionally, extrinsic trade-offs exist between climate impacts and other environmental, economic, and social elements. In formulating future climate policies, we advocate for a holistic assessment from a systematic perspective by the forestry sector, considering both intrinsic and extrinsic challenges, to maximize environmental, economic, and social benefits.