Environmental Life Cycle Assessment of Southern Yellow Pine ...

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EXECUTIVE SUMMARY 800 thousands of tons of CO2 eq. 600 400 200 0 -‐200 -‐400 -‐600 BAU SPR 0 10 20 30 40 Time Horizon (years) Figure 3. A whisker plot of category indicator results for Global Climate Change (Net). The 90% confidence intervals are shown for all results in the time horizon, along with the first and third quartiles for each scenario. As this figure shows, there is an overlap in category indicator results for both the 90% confidence intervals, and the 50% confidence intervals, due to the uncertainties of the results in BAU and SPR scenarios. There are two main factors driving this uncertainty: • For the SPR scenario, the inclusion of the secondary consequences from avoided CCA production. If the secondary consequences are less significant than projected in these findings, the results become ambiguous between the two scenarios. • For both the BAU and SPR scenarios, the large uncertainty in the S-‐CF (the GWP). As noted, the IPCC estimates that GWPs have an uncertainty of ±35%, regardless of the time horizon used. This is a significant level of uncertainty; regardless of the inclusion of secondary consequences in the SPR scenario, the uncertainty in the S-‐CFs means that the two scenarios have a close overlap. This highlights the fact that the uncertainty in results for Global Climate Change, and more generally, those for carbon footprints, is much higher than is commonly understood. Based on this uncertainty analysis, it is estimated that there is an 70% likelihood that the SPR scenario has a lower indicator result for Global Climate Change (Net) after 40 years. These results show that the SPR scenario has an advantage over the BAU scenario for this category indicator, the scale of which is dependent on the size of the secondary consequences resulting from the introduction of steel utility poles. This result casts into question the common assumption that treated wood products have a lower carbon footprint than steel products. Depending on the market effects in the SPR scenario, there may be a marked benefit of the use of steel poles. April 2013 | ©SCS Global Services ES-‐ 12
EXECUTIVE SUMMARY 1.5.2 Lower Land Use Ecological Impacts in Forests in the Southeastern United States While not directly comparable due to the different biomes and species affected, the scale of the results shown in Table 1 indicates that the land use ecological impacts in the SPR scenario are less. When averaged over the 40-‐year time horizon, the results for terrestrial biome disturbance are equivalent to the full disturbance of approximately 12,000 acres for the BAU scenario, compared to approximately 15 acres in the SPR scenario. The differential in the disturbance to wetlands is expected to be even larger; however, insufficient data were available to quantify these results. If data were available, it is anticipated that the differential between the two scenarios could be nearly four orders of magnitude. Based on what is known about wetlands and freshwater habitats in the Southeast US, the number of species impacted in the SPR scenario could be as little as 5% of that in the BAU scenario. This does not consider the impacted floral species, which is again expected to be a longer list for forestry. If data were available to quantify the severity and spatial extent of disturbance to suitable habitat for these species, the BAU scenario is expected to have indicator results three to four orders of magnitude higher than the SPR scenario, for many more species. Given these considerations, the reduction in land use ecological impacts is considered an advantage of the SPR scenario. 1.5.2.1 Land Use Ecological Impacts from Southern Yellow Pine Production 1.5.2.1.1 Terrestrial Biome Disturbance to Forests in the Southeast The United States Forest Service (USFS) estimates that in 2009 in the Southeast, roughly 55 million acres were covered in Loblolly-‐shortleaf pine forests, and 13 million acres were covered in Longleaf-slash forests, the two predominant forest types from which the Southern yellow pine used to produce the wood utility poles is sourced. Most forest management in the region utilizes even-‐aged forestry in “plantation” stands, where entire stands of forest are cut at one time, and allowed to re-grow before being cut again on a regular cycle. In the Southeastern US in 2007, 159 million out of 200 million acres were in plantations, accounting for nearly 80% of all timberland in the region. This type of forest management creates a landscape consisting of a patchwork of forests in different age classes (see Figure 4). April 2013 | ©SCS Global Services ES-‐ 13
Page 1 and 2: FINAL REPORT SCS Global Services
Page 3 and 4: EXECUTIVE SUMMARY 1 EXECUTIVE SUMM
Page 5 and 6: EXECUTIVE SUMMARY Table 1. Summar
Page 7 and 8: EXECUTIVE SUMMARY In North Caroli
Page 9 and 10: EXECUTIVE SUMMARY number of poles
Page 11 and 12: EXECUTIVE SUMMARY 4. Changes in s
Page 13: EXECUTIVE SUMMARY To better under
Page 17 and 18: EXECUTIVE SUMMARY As well as the
Page 19 and 20: EXECUTIVE SUMMARY 1.5.2.1.3 Key Sp
Page 21 and 22: EXECUTIVE SUMMARY • Other survey
Page 23 and 24: EXECUTIVE SUMMARY Indicator result

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