Woody bioenergy demand and carbon sequestration payments increase forest area and produce net carbon benefits.

This study provides a comprehensive assessment of the environmental and economic impacts of climate change on global and regional forests from now through 2200. By integrating the representative concentration pathway (RCP) 2.6 and RCP 8.5 emission scenarios with climate models, a vegetation model, socio-economic scenarios, and a forest economic model, the study explores long run adjustments of both ecosystems and markets to climate change that have not been studied before. The ecological model suggests that global forest productivity increases under RCP 8.5. The overall supply of timber expands faster than demand through the 23rd century lowering timber prices and creating net benefits in the timber sector. Consumers benefit the most from the lower prices but these same low prices tend to damage forest owners, especially in the tropics. Even without a formal sequestration policy, average global forest carbon is projected to increase by 6%–8% by 2100. Under the RCP 2.6, forest carbon remains stable through 2200 but under RCP 8.5 it is simulated to increase by another 8% with a very heterogeneous distribution across world regions. Under both RCPs, global forest area is projected to increase relative to a no-climate change case until 2150, but possibly decline thereafter.

This study examines the effects of supplying forest biomass on forest ecosystem services and goods with a dynamic systems model. This unique analysis models dynamic trade and investments in forestry, thereby capturing price changes from increased forest biomass demand on current and future flows of forest ecosystem services and natural capital stocks. Forests across the globe are interconnected through timber and forest biomass markets, which influence forest management decisions, land rents, and policy responses. Results indicate that expanding forest biomass consumption, even at relatively low levels, will have important impacts on ecosystem services, particularly the benefits of terrestrial carbon sequestration and timber outputs. Increased forest biomass production can be achieved with smaller impacts on ecosystem services through policies targeting natural forest preservation. However, policies that encourage residual biomass use for energy or discourage forest plantation expansion could potentially compromise carbon benefits.

Climate change mitigation policies have usually considered forest-based actions as cheap and fast options to reduce CO 2 concentration in the atmosphere and slow down global warming. Most economic analyses, however, have ignored the effects of these actions on land surface albedo and the resulting effect on energy balance and temperature. This study estimates the marginal cost of forest mitigation associated with both carbon sequestration and albedo change, by introducing regional and forest-specific albedo information in a global dynamic forestry model. Our analysis indicates that traditional forest sequestration policies have underestimated the costs of climate mitigation, driving forest-based actions in regions where subsequent changes in albedo are significant. To reduce this inefficiency, this paper proposes a novel approach where both carbon sequestration and albedo effect are incorporated into pricing. Our results suggest that, under the same carbon price path, the integrative policy provides greater net global mitigation in absolute terms and per hectare of forest, and thus it is more efficient and less intrusive than the traditional policy.

Although most global forest economic studies have found that warming is likely to increase forest supply, these studies have examined only the limited warming expected through 2100. This study extends the analysis out to 2250 to test much higher levels of warming to examine very long term effects. Future warming is predicted to steadily increase forest productivity, with global timber supply predicted to increase through 2250, even with warming up to 11 °C warming. However, natural forestland and biomass will shrink. This result suggests far future forests will not be able to hold the same stock of carbon they hold today.

There is considerable concern that consuming forest biomass for energy will increase net carbon emissions from forests, which is defined as carbon debt. Using a market-based economic model, we test the effects of 51 demand pathways for forest bioenergy on future forest carbon stocks to assess the likelihood of incurring a sustained carbon debt lasting for several decades. We show that potential forest carbon debt from bioenergy expansion, measured as a near-term decrease in forest carbon sequestration relative to a baseline, occurs and persists only under a specific set of assumptions about carbon accounting, markets, policies, and future biomass demands. Finally, we evaluate whether forest regulations restricting biomass sourcing could influence the scale of carbon debt and/or reduce the time needed to recover the carbon debt (payback period). We show that under similar demand pathways and in the absence of direct carbon policies, imposing limits to supply is likely to reduce the payback period but does not avoid initial carbon debt.