Supporting Information for, ‘Climate change impacts due to biogenic carbon: Addressing the issue of attribution using two metrics with very different outcomes’ Process/ parameter Supply and use of woody biomass between industries Desired Data for analysis Data and assumptions used in analysis References HWP/residual flows to and from all relevant domestic industries disaggregated to at least 5 digit resolution SIC codes, and preferably with a list of associated companies that reside within each SIC industry at the give digit resolution. Imported flows at the same SIC resolution is also desired. Accurate account of residuals lost to decomposition or utilized for energy is also desired. Dry mass flow with known carbon content (CC) of each commodity is also needed. Ideally data that describes which input of wood flow goes where for all products with impacts and exports included. We took a material flow analysis of the Norwegian HWP industry (in 2006) which disaggregated between the major HWP industries. The level of resolution is as seen in figure 1. Flows were in solid m3 and tonnes so we converted these flows with representative densities and CC from literature. Regionalized Imports Ideally we would like to know (to 5 digit SIC code resolution) what products are being imported to the domestic country. We used trade statistics which were reported by the Food and Agriculture Organization (FAO) of the United Nations. We then grouped these imports at the nation to nation level into nine continental regions (see tab.2). (FAO 2006) Species type and associated rotation period of each imported product Alongside the desired regionalized imports it would also be ideal to know the specific species and their associated rotation periods for each of the product flows. We used statistics from an FAO survey on nine globally aggregated regions. This survey provided for each region an area distribution of the most prevalent productive woody species alongside data on rotation period and yield per hectare. We took the average rotation period (note only minimum and maximum rotation data) for each species/region and weighted these values by [area*yield/rotation] to arrive to an overall weighted rotation period for each region. (FAO 2006) Dividing flows to and from each process We assume that imported and domestic woody biomass that enters an industry/process has a proportionately (to mass) equal opportunity to end up in each of the output flows. Such a balance was done across each process. Material flow analysis: (Grinde 2006) Densities: Domestic species woody materials: (Korhonen, Wihersaari et al. 2001). Panels: (IPCC 2006). Imported wood species: (Ketterings, Coe et al. 2001) CC: Domestic Species: (Korhonen, Wihersaari et al. 2001) Imported species: (Thomas and Martin 2012); Paper, pulp, panels. (IPCC 2006) Own assumption. Supporting Information Process/ parameter Species type and associated Net Ecosystem Profiles of each imported product Desired Data for analysis As with the rotation periods, it would be ideal to have access to the net ecosystem production (NEP) profile of the biomass resource pool that every imported product was derived from. Species type and associated rotation period of each domestically sourced product Similarly to the imported products we would like to connect all product flows to their species source along with associated rotation period. Species type and associated NEP profiles of each domestically sourced product As with the rotation periods, it would be ideal to have access to the net ecosystem production (NEP) profile of each biomass resource pool that every domestically sourced product was derived from. Data and assumptions used in analysis For all globalized regions (except Europe) we assumed forest residues (FR) left in the forest upon harvest to only be below ground biomass. Standardized allometric factors were used. For Europe we followed the same approach as we used for Norwegian species. However, for all regions we used the Yasso07 model with assumed average annual regionalized temperature and precipitation satellite based data from NASA. Chemical compositions of important regional species were used as Yasso07 inputs. All global regions were assumed to have net primary productivity profiles (NPP) following log normal distribution curves. The resulting FR and NPP profiles were used to calculate the NEP profiles. We used Norwegian specific statistics which reported species dominated area distributions and their site quality classes. From this data we calculated the area weighted average site quality for each of the three main species, Norway Spruce, Scots Pine and Birch. We then used national guidelines that relate the suitable minimum age (age class V) when a stand can be cut for each site quality index. With these two data items we were able to deduce an average rotation period for each forest species. Both Norway Spruce and Scots pine worked out to be about 100 years while Birch was around 70 years rotation period. The overall weighted average rotation period remained to be about 99 years since there was not a lot of Birch harvested relative to the other dominating species Scots Pine and Norway Spruce. We made assumptions about the forest residues left in the forest along with using allometric equations and in addition to this we assumed annual turnover of the tree components and natural deaths of whole trees. This was coupled with an assumed NPP profile. For Norway Spruce and Scots pine we assumed a Schnute function whereas for Birch we assumed a log normal distribution. We used Yasso07 where monthly average temperature and precipitation data was used and this data was representative of the region of Norway where the majority of forestry takes place. 2 References Allometric factors: IPPC 2006 Europe FR decomposition: (Guest, Cherubini et al. 2012) . Yasso07 model: (Tuomi, Thum et al. 2009); (Pettersen 1984). Temperature and Precipitation data: (NASA 2013) Area distribution of species specific quality classes: (Larsson and Hylen 2007) and (Landskap 2007). See Guest et al. (2012) for all assumptions with regards to the methods of attaining these NEP profiles. Supporting Information Process/ parameter Decomposition curves of HWPs Desired Data for analysis Data and assumptions used in analysis References Ideally we would have liked to know an estimated mean life time of HWPs disaggregated to 5-digit resolution SIC codes. In practice it would also be ideal to have perfect knowledge of the lifetime of each product at its end-oflife. We take estimated half-lives for 15 products based on data from the United States forest product economy. We adopt these values by converting them to mean life-times (dividing half-life by ln(2)). We then applied a chi-square distribution to represent the probability distribution profile of each HWP coming to its end-of-life. HWP life times: (Smith, Heath et al. 2006) Chi-Square Distribution: Cherubini et al.2012. Determining how primary HWPs are being used in final HWPs As stated earlier it would be ideal to know the HWP flow through all industries that deal with HWPs (with at least 5-digit SIC resolution). (Smith, Heath et al. 2006) Glue laminated case example This was an arbitrary example of a HWP value chain that fit within our study. Similar value chains should be constructed for all HWPs using primary data from the industries that actually produce the given HWPs. Since the material flow analysis stopped only at primary HWP products (i.e. panels, and sawn wood) we needed to determine how these resources will likely be used. Again we used available data from the United States forest product economy where a table provides percentage breakdowns of where primary HWPs end up into final HWPs. We devised our bio-C balance across this value chain based on a life cycle inventory study. Construction wastes were based on a US report. Life cycle inventory: (Werner, Althaus et al. 2007). Construction waste fraction: (Smith, Heath et al. 2006). 3 Supporting Information <Figure S1: Standard Industrial Codes at 5-digit resolution categorized into the several party groups (PG) that constitutes the HWP value chain> When any of the SIC codes has an x it means that the industry is not defined under the SIC standard but was found to be an important industry to disaggregate at this resolution for the HWP value chain system. 4 Supporting Information Examples of attribution tables for the other value chain combinations as according to the above PG categorization. When using the PG categories as depicted in fig.S1, then there can be a total of 5 value chain combinations to consider. The following are examples of what the attribution tables could look like for each of these value chains. By applying these or similar tables, then it can be quite straight forward to understand how much of the climate change impact should be attributed to each PG, and these impacts can be further disaggregated across companies from within the given PG. Depending on the given value chain, there could be several companies within a PG that contribute to the production of a product. Also, there may not necessarily be third party brokerage companies involved at each step of the value chain. Also, local scale projects, that are for the most part privately undertaken, would involve a simpler accounting framework. The numbers presented in each table below are solely based on the judgment of the authors. In practice they would need to be negotiated amongst those parties that contribute to the given HWP value chain. Value chain a: forest >tier 1 HWPs>tier 2 HWPs >HWP end use & construction/manufacturing waste bioenergy PGs involved in the processing, manufacturing and other non-brokerage services PGs invovled in the brokerage of production PG 1: Timber PG 2: Tier 1 HWP PG 3: Tier 2 HWP PG 6: End use PG 7: End use PG 8: Timber PG 9: Tier 1 HWP PG 10: Tier 2 PG 13: End producers producers producers collectors producers brokers brokers HWP brokers use (waste) c1: Forest biomass production 1 0 0 0 0 0 0 0 0 c2: Brokering tree product 0 0 0 0 0 1 0 0 0 c3: Primary product 0,1 0,4 0,5 0 0 0 0 0 0 c4: Brokering primary product 0 0 0 0 0 0 0,4 0,6 0 c5: Enduse product 0 0 0 0,2 0,8 0 0 0 0 c6: Brokering end use proudct 0 0 0 0 0 0 0 0 1 Attribution Fraction 0,24 0,16 0,2 0,02 0,08 0,1 0,04 0,06 0,1 Σc1,j U 1 1 1 1 1 1 1 0,2 0,1 0,4 0,1 0,1 0,1 1 Value chain b: forest > tier 1 paper production>tier 2 paper production> bioenergy PG involved in the processing, manufacturing and other non-brokerage services c1: Forest biomass production c2: Brokering tree product c3: Primary product c4: Brokering primary product c5: Enduse product c6: Brokering end use proudct Attribution Fraction PG 1: Timber PG 2: Tier 1 HWP PG 4: Tier 1 producers producers paper producers 1 0 0 0 0 0 0 0,2 0,3 0 0 0 0 0 0 0 0 0 0,20 0,08 0,12 PG 5: Tier 2 paper 0 0 0,4 0 0 0 0,16 PG 6: End-use PG 7: End use collectors producers 0 0 0 0 0,05 0,05 0 0 0,2 0,8 0 0 0,04 0,10 5 PGs invovled in the brokerage of production PG 8: Timber brokers 0 1 0 0 0 0 0,10 PG 9: Tier 1 PG 11: Tier 1 PG 12: Tier 2 PG 13: End use HWP brokers paper brokers paper brokers (waste) brokers 0 0 0 0 0 0 0 0 0 0 0 0 0,1 0,3 0,6 0 0 0 0 0 0 0 0 1 0,01 0,03 0,06 0,10 Σc1,j U 1 1 1 1 1 1 1 0,2 0,1 0,4 0,1 0,1 0,1 1 Supporting Information Value chain c: forest > bioenergy PGs involved in the processing, manufacturing and other nonbrokerage services PG 1: Timber PG 7: End use producers producers c1: Forest biomass production 1 0 c2: Brokering tree product 0 0 c3: Primary product 0,2 0,8 c4: Brokering primary product 0 0 Attribution Fraction 0,35 0,4 Parties invovled in the brokerage of production PG 8: Timber brokers 0 1 0 0,4 0,175 PG 13: End use (waste) 0 0 0 0,6 0,075 Σc1,j U 1 1 1 1 1 0,25 0,13 0,50 0,13 1 Value chain d: forest > tier 1 HWP residues > bioenergy PGs involved in the processing, manufacturing and other nonbrokerage services PGs invovled in the brokerage of production PG 1: Timber PG 2: Tier 1 HWP PG 6: End use PG 7: End use PG 8: Timber PG 9: Tier 1 PG 13: End use producers producers collectors producers brokers HWP brokers (waste) brokers c1: Forest biomass production 1 0 0 0 0 0 0 c2: Brokering tree product 0 0 0 0 1 0 0 c3: Primary product 0,3 0,7 0 0 0 0 0 c4: Brokering primary product 0 0 0 0 0 1 0 c5: Enduse product 0 0 0,2 0,8 0 0 0 c6: Brokering end use proudct 0 0 0 0 0 0 1 Attribution Fraction 0,32 0,28 0,02 0,08 0,1 0,1 0,1 6 Σc1,j U 1 1 1 1 1 1 1 0,2 0,1 0,4 0,1 0,1 0,1 1 Supporting Information Value chain e: forest > tier 1 paper production> bioenergy PG involved in the processing, manufacturing and other nonPGs invovled in the brokerage of production brokerage services PG 1: Timber PG 4: Tier 1 PG 6: End-use PG 7: End use PG 8: Timber PG 11: Tier 1 PG 13: End use producers paper producers collectors producers brokers paper brokers (waste) brokers c1: Forest biomass production 1 0 0 0 0 0 0 c2: Brokering tree product 0 0 0 0 1 0 0 c3: Primary product 0,1 0,2 0,2 0,5 0 0 0 c4: Brokering primary product 0 0 0 0 0 1 0 c5: Enduse product c6: Brokering end use proudct 0 0 0 0 0 0 1 Attribution Fraction 0,27 0,09 0,09 0,22 0,11 0,11 0,11 7 Σc1,j U 1 1 1 1 0,2 0,1 0,4 0,1 1 1 0,1 1 Supporting Information 3 BRP FR decomposition 8 Energy/losses fast Paper 6 HWPs (u=9-144 yrs) Global Ocean/Terrestrial Atmosphere 4 BRP regrowth of bio CO2 emitted BRP regrowth other CO2 2 0 0 2 Time, years x 10 7.5 Instantaneous Radiative Forcing (RF) Instantaneous Surface Temperature Change (AGTP) Integrated Radiative Forcing (iRF) 100 150 5 1 2.5 0 0 -1 -2 0 50 -6 2 Biogenic C balance [tonnes C] 10 x 10 100 200 300 Time, years 400 -5 2 x 10 iAGWP [Watt-years/m ] 12 b) 5 AGWP [Watts/m ] or AGTP [Kelvin] a) -2.5 500 Figure S2: a) Dynamic profile of the bio-C balance; b) Instantaneous and integrated radiative forcing and surface temperature change over time for Norwegian HWP 2006 imported HWPst used domestically; all biomass in HWP residues and HWP at end of life is assumed to be utilized for bioenergy or otherwise oxidized as CO2 to the atmosphere> Since the weighted average rotation period was calculated to be about 70 years for the imported biomass, the CO2 emitted to the atmosphere is sequestered significantly faster than the Norwegian biomass/HWP case with a weighted average rotation period of 99 years as is shown in fig.S2 above. In the import system for domestic use (as depicted in fig.1 of the manuscript (blue values)) we apply the mirrored economy assumption to describe the produced HWPs that are then imported to Norway. Since a great majority of the biomass is imported from within Europe, it is reasonable to assume that biomass losses and residual energy demands across the different processing stages are quite similar to those found for Norway. 8 Supporting Information References: FAO. (2006). "FAOSTAT " Retrieved 6.6.2010, 2010, from http://faostat.fao.org/site/406/default.aspx. FAO (2006). Global planted forests thematic study: results and analysis. Planted Forests and Trees Working Paper 38. J. B. by A. Del Lungo, J.Carle. . Rome. Grinde, M. (2006). Environmental Assessment of Scenarios for Products and Services based on Forest Resources in Norway. Department of Energy and Process Engineering. Trondheim Norwegian University of Science and Technology. Masters: 88. Guest, G., F. Cherubini, et al. (2012). 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