Apparent Half-Life-Dynamics of Harvested Wood Products (HWPs) in Austria: Development and analysis of weighted time-series for 2002 to 2011

• Harvested Wood Products (HWPs) are considered as means of carbon storage in the second commitment period of the Kyoto Protocol. The Half-Life (HL) is an important factor in calculating and reporting of carbon storage in HWP.
• The paper presents a practical way to calculate country specific HLs
• The average calculated Kyoto-relevant HL was 9.5 to 16.6 years for sawnwood and 9 to 11 years for wood based panels respectively.
• Finally this work shows that an increasing amount of Austria’s finished HWP is going into long-lived constructional structures where it sequesters carbon for longer periods.

Harvested Wood Products (HWPs) are considered as means of carbon sequestration in the second commitment period of the Kyoto Protocol. The Intergovernmental Panel on Climate Change (IPCC) has introduced the average (service) life multiplied by ln(2) as so-called “Half-Life” (HL) to define the period for accounting carbon sequestration in wood products.This work investigates the dynamics of apparent HL and carbon content within three important categories of wood utilization (construction, furniture and packaging) considering sales on the wood product level in Austria for the period 2002 to 2011. Static HL for finished products derived from a literature study is used for upscaling information about carbon flows and associated HL to semi-finished HWP. From HL on the product level three category-HLs are derived. Averaged over 10 years, we find the following HLs: 33.0 years for construction, 8.5 years for furniture, and 1.4 years for packaging. For each category the shares of semi-finished HWP (sawnwood and wood-based panels) are determined. With this information, the average Kyoto-relevant HL for semi-finished HWP can be deducted. For the period 2002–2011, it is 9.5 to 16.6 years for sawnwood and 9.0 to 11.0 years for wood-based panels.