IPCC Report Cites Value of Wood Products to Mitigate Climate Change

Some key climate change mitigation benefits from the use of wood have been cited by the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment report on Mitigation of Climate Change.

WGIII_AR5_Cover_webOne key measure related to slowing down, or mitigating, the rate of climate change impacts is greenhouse gas (GHG) emissions. In general the report finds that “Provision of products with low GHG emissions can replace products with higher GHG emissions for delivering the same service (e.g., replacement of concrete and steel in buildings with wood, [and] some bioenergy options).” [p 22]

According to economist Ken Skog, supervisory research forester and leader of the Economics, Statistics and Life Cycle Analysis Research group at FPL, the report “confirms findings that efforts to expand use of wood in long-lived applications such as multistory buildings are a key means to hold down GHG emissions and mitigate climate change.”

Skog

Ken Skog, FPL supervisory research forester and economist

Specifically, the report cites research indicating wood-based wall systems use 10 – 20% less embodied energy than traditional concrete wall systems. Concrete-framed buildings, in turn, use less embodied energy than their steel-framed counterparts.

The report states that “increased wood use does not reduce GHG emissions under all circumstances.” Wood harvest “reduces the amount of carbon stored in the forest, at least temporarily, and increases in wood harvest levels may result in reduced long?term carbon storage in forests.”

However, research shows that reducing wood consumption through paper recycling, for example, can reduce GHG emissions, and using wood grown in sustainable forestry systems, rather than “emission intensive materials such as concrete, steel, or aluminium” can further reduce emissions, mitigating the long-term effects of climate change.

Using wood from sustainably managed forests rather than non?wood materials in the construction sector (concrete, steel, etc.), research shows, reduces GHG emissions in most cases throughout the construction process for single family homes, apartment houses, and industrial buildings. Most emission reductions in this process result from reduced production emissions rather than carbon sequestration in products, which “is relatively small.”

Greenhouse gas benefits are highest, the report states, “when wood is primarily used for long?lived products, the lifetime of products is maximized, and energy use of woody biomass is focused on by?products, wood wastes, and end?of lifecycle use of long?lived wood products.”

 

The Trade-offs of Carbon Storage and Climate Change Mitigation Strategies

Storing carbon in standing trees can help offset greenhouse gas emissions but will also affect future timber supply and prices. A recent study published in the Canadian Journal of Forestry Research analyzes the impacts of this particular set of trade-offs. The study, Projected US timber and primary forest product market impacts of climate change mitigation through timber set-asides, is available through the U.S. Forest Service Research and Development database TreeSearch.

Prakash

Prakash Nepal, post-doctoral economist at FPL

Lead author Prakash Nepal, a post-doctoral economist at the Forest Products Laboratory, developed several hypothetical timber set-aside scenarios where a portion of U.S. forest landowners would be paid to forego timber harvests for 100 years. Allowing standing timber to grow and healthy forests to prosper increases the amount of stored carbon and mitigates climate change through the capture of greenhouse gasses such as carbon dioxide.

Reducing the amount of available timberland for harvest, this analysis found, would increase timber prices and affect U.S. domestic timber production, consumption, net export, and timber market welfare. Nepal, along with co-investigators Peter Ince and Ken Skog from FPL and Sun J. Chang of Louisiana State University’s School of Renewable Natural Resources, conclude that policymakers considering future climate change mitigation policies and programs should take into account such carbon-storage/timber-price trade-offs when developing mitigation strategies in the forest sector.