Sea level rise (SLR) is among the climate-change-related problems of greatest concern, threatening the lives and property of coastal residents and generating far-reaching economic and ecological impacts. We project that SLR will lead to an increase in the rate of new housing construction to replace destroyed structures, impact global wood products supply and demand conditions, and cause changes in global forest sector carbon mitigation potential. Findings indicate that 71 million new units will be built by 2050 to accommodate the SLR-affected global population. More than two-thirds of these new units are projected to be in Asia. The estimated extra wood products needed to build these new residential units is 1,659 million m3, assuming that all these structures would be built mainly with wood, representing a 4 % increase in total wood consumption, compared to projected reference level global wood products consumption. Increased timber removals to meet this higher construction wood demand (alternative scenario) is shown to deplete global forest carbon by 2 % by 2050 compared to the reference scenario. However, all such projected declines in forest biomass carbon could be more than offset by increased carbon sequestration in harvested wood products, avoided emissions due to substitution of wood for non-wood materials in construction, and biomass regrowth on forestland by 2050, with an estimated net emissions reduction benefit of 0.47 tCO2e/tCO2e of extra wood used in SLR-related new houses over 30 years. The global net emissions reduction benefit increased to 2.13 tCO2e/tCO2e of extra wood when price-induced changes in forest land area were included.

Using a partial market equilibrium framework, this study evaluated the US regional timber and wood products market impacts of a projected national level expansion in wood biomass consumption for energy. By restricting logging residue use, we focus on the impacts on timber harvests and paper production from increased pulpwood consumption and focus on the impacts on lumber production from increased mill residue consumption. Analyses showed that increased consumption of wood for energy led to diversion of about 37 million m(3) of pulpwood away from pulpwood-using traditional products (e.g., panels and paper), reducing production and net exports of paper and paperboard by up to 3 million tonnes. Increased wood energy consumption also led to increased timber harvests (up to 40 million m(3) or 8 percent), increased prices (up to 31 percent), and increased lumber production and net exports by up to 9 million m(3). The South was projected to supply the majority of the energy feedstock (47 m(3) or 77 percent) and to experience the resultant effects on forests and wood products sectors. The findings highlight the importance of market linkages at local, national, and global levels in evaluating the impacts of increased wood energy consumption and the importance of identifying feedstock sources.

The social and economic benefits of wood harvest from forests depend on the demand for different ecosystem services, including products desired from trees. Although uses of species such as Douglas-fir and western hemlock for finished lumber, plywood, and paper have dominated past demand in moist coniferous forests of the Pacific Northwest, the emergence of new uses and technologies has expanded opportunities for wood utilization. This changes what, when, and how wood is harvested from the forest and how different management activities may intersect with restoration targets and ecosystem services—some of which are only just emerging.

Consumption of renewable energy in the United States is the highest in history, contributing to energy security, greenhouse gas reductions, and other social, economic, and environmental benefits. The largest single source of renewable energy is biomass, representing 3.9 quadrillion of 9.6 quadrillion British thermal units (Btu) in 2015 (EIA 2016). Biomass includes agricultural and forestry resources, municipal solid waste (MSW), and algae. For more than a decade, the US Department of Energy (DOE) has been quantifying the potential of US biomass resources, under biophysical and economic constraints, for production of renewable energy and bioproducts. The 2016 Billion-Ton Report: Advancing Domestic Resources for a Thriving Bioeconomy (BT16) evaluates the most recent estimates of potential biomass that could be available for new industrial uses in the future. BT16 consists of two volumes: Volume 1 (this volume) focuses on resource analysis—projecting biomass potentially available at specified prices. Volume 2 evaluates changes in environmental sustainability indicators—water quality and quantity, greenhouse gas emissions, air quality, soil organic carbon, and biodiversity—associated with select production scenarios in volume 1. The following is a summary of BT16, volume 1.

More wood use in the United States to construct low-rise nonresidential (NR) buildings would increase consumption and production of softwood (SW) lumber, engineered wood products, and structural and nonstructural wood panels. Using a consequential life-cycle analysis, we estimated the change in net CO2 emissions that would be caused by increased use of SW lumber and structural panels in NR construction. Carbon (C) storage and emissions were projected over 50 years for baseline and increased wood use scenarios using the US Forest Products Module operating within the Global Forest Products Model (USFPM/GFPM) and the Southern region timber supply model (SRTS). Increased wood use in NR. construction (C content of 428 million tons of carbon dioxide equivalent [tCO(2)e]) could provide an emissions reduction of 870 million tCO(2)e over 50 years or a net emissions reduction of 2.03 tCO(2)e/tCO(2)e of extra wood used in NR buildings over 50 years. The CO2 savings varied for products provided in the South, North, and West because of differences in biological timber regrowth; market-induced changes in land use; differences in timber harvests, lumber, and structural panel production; and associated differences in C stored in forests, harvested wood products, logging slash, and manufacturing emissions. The US South provided the largest net change, -2.83 tCO(2)e/tCO(2)e of extra wood products, followed by the North and West with -1.89 and -0.60 tCO(2)e/tCO(2)e of extra wood, respectively. These results suggest strategies that result in increased use of wood in place of nonwood products in NR buildings would be effective in mitigating CO2 emissions.

Use of wood biomass for energy results in carbon (C) emissions at the time of burning and alters C stocks on the land because of harvest, regrowth, and changes in land use or management. This study evaluates the potential effects of expanded woody biomass energy use (for heat and power) on net C emissions over time. A scenario with increased wood energy use is compared with a dynamic business‐as‐usual scenario where wood energy use is driven by its historical relationship with gross domestic product. At the national level, we projected that up to 78% of increased cumulative C emissions from increased wood burning and up to 80% of increased cumulative radiative forcing would be offset over 50 years by change in forest area loss, biomass regrowth on land, C storage in harvested wood products, and C in logging slash left in forests. For example, forest area is projected to decline in both scenarios, but 3.5 million hectares more are retained in the high wood energy‐use case. Projected C offsets over a 50 year period differed substantially by US region (16% in the North, 50% in the West, and 95% in the South) not only because of differences in forest regrowth and induced investment in retaining and planting forest, but also because of shifts in competitive advantage among regions in producing various wood products. If wood systems displace coal systems that have 75% of the C emissions of wood energy systems per unit energy, then the nationwide net C emissions offset would be reduced to 71–74%. If displacing natural gas systems that have 40% of the level of wood bioenergy emissions per unit energy, the nationwide net C emissions offset would be 46–52%.

come from teaching and research institutions in France or abroad, or from public or private research centers.L'archive ouverte pluridisciplinaire

Four research-based insights are essential to understanding forest bioenergy and "carbon debts." (1) As long as wood-producing land remains in forest, long-lived wood products and forest bioenergy reduce fossil fuel use and long-term carbon emission impacts. (2) Increased demand for wood can trigger investments that increase forest area and forest productivity and reduce carbon impacts associated with increased harvesting. (3) The carbon debt concept emphasizes short-term concerns about biogenic CO2 emissions, although it is long-term cumulative CO2 emissions that are correlated with projected peak global temperature, and these cumulative emissions are reduced by substituting forest bioenergy for fossil fuels. (4) Considering forest growth, investment responses, and the radiative forcing of biogenic CO2 over a 100-year time horizon (as used for other greenhouse gases), the increased use of forest-derived materials most likely to be used for bioenergy in the United States results in low net greenhouse gas emissions, especially compared with those for fossil fuels.

A key component in describing forest carbon (C) dynamics is the change in downed dead wood biomass through time. Specifically, there is a dearth of information regarding the residence time of downed woody debris (DWD), which may be reflected in the diversity of wood (for example, species, size, and stage of decay) and site attributes (for example, climate) across the study region of eastern US forests. The empirical assessment of DWD rate of decay and residence time is complicated by the decay process itself, as decomposing logs undergo not only a reduction in wood density over time but also reductions in biomass, shape, and size. Using DWD repeated measurements coupled with models to estimate durations in various stages of decay, estimates of DWD half-life (T HALF), residence time (T RES), and decay rate (k constants) were developed for 36 tree species common to eastern US forests. Results indicate that estimates for T HALF averaged 18 and 10 years for conifers and hardwoods, respectively. Species that exhibited shorter T HALF tended to display a shorter T RES and larger k constants. Averages of T RES ranged from 57 to 124 years for conifers and from 46 to 71 years for hardwoods, depending on the species and methodology for estimating DWD decomposition considered. Decay rate constants (k) increased with increasing temperature of climate zones and ranged from 0.024 to 0.040 for conifers and from 0.043 to 0.064 for hardwoods. These estimates could be incorporated into dynamic global vegetation models to elucidate the role of DWD in forest C dynamics.

Use of woody biomass from sustainably managed sources to produce energy is considered an important strategy to mitigate climate change because the resource is renewable (biomass regrowth on land recaptures emitted carbon dioxide (CO2) due to biomass burning) and can substitute for fossil-fuel-based energy such as coal and natural gas. However, consensus on the degree of contribution of woody biomass to climate change mitigation is lacking. The reason for this lack of consensus is that different analysts include different carbon (C) stock changes (e.g. C stock change where feedstock is taken, C stock change due to indirect land use and management changes), different time frames (e.g. 10-20years versus 100 years), different greenhouse gas (GHG) metrics (e.g. GHG flux versus net cumulative radiative forcing), different types and sources of wood feedstock (e.g. feedstock sourced from existing forest versus feedstock sourced from new plantations versus use of logging residue), different baselines (e.g. reference point baseline versus anticipated future baseline), and types of life cycle analysis (LCA) framework (e.g. attributional LCA versus consequential LCA) that influence the estimated GHG impacts of wood energy.

Current policies in the European Union (EU) requiring renewable and low greenhouse gas-emitting energy are affecting wood products manufacturing and forests in the United States. These policies have led to increased U.S. pellet production and export to the EU, which has in turn affected U.S. forests and other wood products manufacturing. At this time, the primary exporting region in the United States is the South, and the primary importing countries in the EU are the United Kingdom, Belgium, and the Netherlands. The policies and some Member State subsidies are expected to continue in place until at least 2020, with the potential to continue beyond that date. Key drivers of U.S. pellet feedstock supply include both the age structure of current timber inventory and the policies that define sustainability. Also influencing the effect of increased demand for timber for pellets are the price-inelastic supply and demand. A simulation of the market responses to increases in both pellet and other bioenergy demand in the U.S. South suggests that prices will increase for timber as harvest increases, and will in turn lead to long-term changes in inventory and forest land area.

Wood products have many environmental advantages over nonwood alternatives. Documenting and publicizing these merits helps the future competitiveness of wood when climate change impacts are being considered. The manufacture of wood products requires less fossil fuel than nonwood alternative building materials such as concrete, metals, or plastics. By nature, wood is composed of carbon that is captured from the atmosphere during tree growth. These two effects-substitution and sequestration-are why the carbon impact of wood products is favorable. This article shows greenhouse gas emission savings for a range of wood products by comparing (1) net wood product carbon emissions from forest cradle-to-mill output gate minus carbon storage over product use life with (2) cradle-to-gate carbon emissions for substitute nonwood products. The study assumes sustainable forest management practices will be used for the duration of the time for the forest to regrow completely from when the wood was removed for product production during harvesting. The article describes how the carbon impact factors were developed for wood products such as framing lumber, flooring, moulding, and utility poles. Estimates of carbon emissions saved per unit of wood product used are based on the following: (1) gross carbon dioxide (CO2) emissions from wood product production, (2) CO2 from biofuels combusted and used for energy during manufacturing, (3) carbon stored in the final product, and (4) fossil CO2 emissions from the production of nonwood alternatives. The results show notable carbon emissions savings when wood products are used in constructing buildings in place of nonwood alternatives.