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Due to the record-breaking wildfires that occurred in Canada in 2023, unprecedented quantities of air pollutants and greenhouse gases were released into the atmosphere. The wildfires had emitted more than 1.3 Pg CO2 and 0.14 Pg CO2 equivalent of other greenhouse gases (GHG) including CH4 and N2O as of 31 August. The wildfire-related GHG emissions constituted more than doubled Canada's planned cumulative anthropogenic emissions reductions in 10 years, which represents a significant challenge to climate mitigation efforts. The model simulations showed that the Canadian wildfires impacted not only the local air quality but also that of most areas in the northern hemisphere due to long-range transport, causing severe PM2.5 pollution in the northeastern United States and increasing daily mean PM2.5 concentration in northwestern China by up to 2 µg m−3. The observed maximum daily mean PM2.5 concentration in New York City reached 148.3 µg m−3, which was their worst air quality in more than 50 years, nearly 10 times that of the air quality guideline (i.e., 15 µg m−3) issued by the World Health Organization (WHO). Aside from the direct emissions from forest fires, the peat fires beneath the surface might smolder for several months or even longer and release substantial amounts of CO2. The substantial amounts of greenhouse gases from forest and peat fires might contribute to the positive feedback to the climate, potentially accelerating global warming. To better understand the comprehensive environmental effects of wildfires and their interactions with the climate system, more detailed research based on advanced observations and Earth System Models is essential. [ABSTRACT FROM AUTHOR]

Canadian climate service providers offer projections from the Coupled Model Intercomparison Project (CMIP6) to help inform climate change mitigation and adaptation decisions. CMIP6 includes several "hot" climate models whose sensitivity to greenhouse gas forcings exceeds the likely range inferred from multiple lines of evidence. Global warming estimates assessed in the Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC) were reduced by applying observational constraints on the historical rate of warming to the CMIP6 ensemble. This study assesses whether globally constrained CMIP6 projections for Canada are appreciably different from unconstrained projections. Two constraints are considered: one that removes models whose transient climate response lies outside the AR6 assessed range (TCRlikely), and the other that weights models to match the assessed distribution of equilibrium climate sensitivity (ECSall). Both constraints lead to appreciably cooler and drier projections than the unconstrained ensemble, with the strongest reductions seen in the upper end of the ensemble range, high-emissions scenario, end-of-century time period, and northern regions of Canada. In this case, constrained projections of annual mean temperature are 2°–3°C cooler than the unconstrained projections, whereas projections of annual total precipitation are typically 20%–40% drier. Appreciable differences are also detected in the ensemble median of temperature extreme indices. Based on these results, it is recommended that a constrained ensemble be considered for regional projections to avoid the "hot model" problem. Alternatively, projections can be communicated conditional on a specified level of global warming, with global constraints then used to inform the timing of the warming level exceedance. [ABSTRACT FROM AUTHOR]

With its northern location, the exposure and vulnerability of Canada's forest ecosystems to climate change impacts are all too glaring. While there is now an extensive body of literature describing expected climate change impacts and potential responses, studies characterizing the implementation of adaptation and mitigation practices in forest management remain rare in the Canadian forest sector. Using a systematic literature review, we examined reports on forest management practices implemented in response to climate change, specifically focusing on governance and institutional arrangements that either support or limit climate change adaptation and mitigation responses. Our literature sample size of 24 documents suggests that the body of literature reporting on adaptation and mitigation practices in forest management is scarce. Governments remain the dominant actors providing funding and leading the implementation and reporting of climate change adaptation practices, primarily in response to national or international climate change commitments. Forest practices such as enhanced silviculture, assisted migration, and nature-based solutions were the most frequently reported. However, given the scarcity of literature, it is difficult to conclude the scope of climate change adaptation practice uptake in Canada. Barriers such as lack of information/data, inter-jurisdictional knowledge transfer, policy conflicts, forest tenure models, technical capacity gaps, and economic barriers to adaptation need to be overcome to strengthen climate change response in forest management. Better coordination of reporting at the provincial and national levels and improved information flows between private sector organizations and governments are needed. [ABSTRACT FROM AUTHOR]

Canada is recognized as a global leader in sustainable forest management. Canadian forests and the forest sector remain vital pillars of the Canadian economy and home to many rural and remote communities. However, climate change is an existential threat to the sustainability of forests and forest-dependent communities. While both direct and indirect threats posed by climate change to Canada's forest sector are now well understood, our understanding of specific forest practices that have emerged from the body of science to mitigate and adapt to climate change impacts is not well documented. Through a review of the scientific and grey literature, this study expands our knowledge and operational gaps associated with implementing climate change adaptation and mitigation practices in Canadian forests. The study found a dearth of literature specifically dedicated to reporting on the type of forest practices currently in use across Canada to address mitigation and adaptation. Most reports or studies were published in 2019 or later, with federal and provincial governments being the dominant actors in reporting and monitoring, research, and funding. Across the 15 terrestrial ecozones in Canada, forest practices linked to climate change were reported in 12 ecozones, with most practices reported in the Montane Cordillera located in western Canada. Common forest practices reported include fuel management, assisted migration, enhanced silvicultural activities, and carbon offset projects. We conclude that climate change adaptation/mitigation practices in Canada are in their early stages of implementation. Many practices remain in experimental stages (e.g., genetic trials) or are implemented at a relatively small scale in Canada (e.g., climate-based seed transfer and carbon reserves). The literature suggests that the most mainstream practices associated with climate change mitigation in Canada include tree planting for carbon sequestration and the designation of protected areas to enhance ecosystem resilience. We conclude that despite increasing reports linking climate change benefits with reported forest practices, the reporting in the scientific literature is scarce, poorly reported, and often not grounded in credible evidence. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this empirical case study is to study and explain the role of public leadership in the expansion of municipal climate action in Canada. Design/methodology/approach: In 2017 and 2018, the authors conducted13 semi-directed interviews with municipal staff and elected officials from three municipalities, a documentary analysis of primary and secondary sources. Interviews and documentation collected were also coded using the software NVIVO 12. The authors compared three municipal case studies: the City of Toronto (Ontario), the City of Guelph (Ontario), and the Town of Bridgewater (Nova Scotia). Findings: The authors found that leadership is a prominent factor explaining the expansion of municipal climate action in Canada. Municipal climate action is initiated and championed by an individual, elected officials or municipal staff, who lead and engage in the development of policy instruments to mitigate and/or adapt to climate change. These leaders facilitate the formulation and implementation of instruments, encourage a paradigm shift within the municipality, overcome structural and behavioural barriers, and foster collaboration around a common vision. Optimal municipal climate leadership occurs when the leadership of elected officials and municipal is congruent, though networks play a significant role by amplifying municipal sustainability leadership. They support staff and elected officials leadership within municipalities, provide more information and funding to grow the capacity of municipalities to develop instruments, to the point that conditions under which municipalities are driving climate action are changing. Research limitations/implications: This paper hopes to contribute to better understand under what conditions municipalities drive change. Originality/value: There is an international scholarly recognition that municipalities should be further explored and considered important actors in the Canadian and international climate change governance. Gore (2010) and Robinson and Gore (2015) highlighted that we are yet to understand the extent to which municipalities are involved in climate governance in Canada. This article directly addresses this gap in the current scholarly literature and explores the expansion of climate municipal leadership with the aspects of interviews. [ABSTRACT FROM AUTHOR]

Over the last few decades, there has been an increasing recognition for seagrasses' contribution to the functioning of nearshore ecosystems and climate change mitigation. Nevertheless, seagrass ecosystems have been deteriorating globally at an accelerating rate during recent decades. In 2017, research into the condition of eelgrass (Zostera marina) along the eastern coast of James Bay, Canada, was initiated in response to reports of eelgrass decline by the Cree First Nations of Eeyou Istchee. As part of this research, we compiled and analyzed two decades of eelgrass cover data and three decades of eelgrass monitoring data (biomass and density) to detect changes and assess possible environmental drivers. We detected a major decline in eelgrass condition between 1995 and 1999, which encompassed the entire east coast of James Bay. Surveys conducted in 2019 and 2020 indicated limited changes post‐decline, for example, low eelgrass cover (<25%), low aboveground biomass, smaller shoots than before 1995, and marginally low densities persisted at most sites. Overall, the synthesized datasets show a 40% loss of eelgrass meadows with >50% cover in eastern James Bay since 1995, representing the largest scale eelgrass decline documented in eastern Canada since the massive die‐off event that occurred in the 1930s along the North Atlantic coast. Using biomass data collected since 1982, but geographically limited to the sector of the coast near the regulated La Grande River, generalized additive modeling revealed eelgrass meadows are affected by local sea surface temperature, early ice breakup, and higher summer freshwater discharge. Our results caution against assuming subarctic seagrass ecosystems have avoided recent global declines or will benefit from ongoing climate warming. [ABSTRACT FROM AUTHOR]

Recent global warming has caused significant changes to the regional climate over Eastern Canada and brought unprecedented challenges to the local communities, such as rising sea level, shrinking sea ice coverage, increasing coastal and inland floods, accelerated coastal erosion, and so on. Although local governments have declared climate emergency in recent years, there is still a lack of real climate actions due to the poor understanding of the future climatic changes over Eastern Canada and how to mitigate and adapt to those changes from a long-term perspective. Here we attempt to fill this gap by developing high-resolution regional climate scenarios for Eastern Canada throughout the twenty-first century under three greenhouse gases emission scenarios (RCP2.6—low, RCP4.5—medium, and RCP8.5—high). The results suggest that the low-emission scenario of RCP2.6 would potentially stabilize the regional climate (i.e., no significant changes in both temperature and precipitation) over Eastern Canada after the continuous warming reaches its peak in the middle of this century. However, an average warming about 1 °C would still be expected from now to the end of this century under RCP2.6, highlighting the importance of preparing for a new climate normal even though strict carbon reduction efforts could be made before 2050. In comparison, both RCP4.5 and RCP8.5 scenarios would lead to a continuous warming over Eastern Canada with increased total precipitation throughout this century. Most importantly, the warming trend under RCP8.5 is likely to accelerate after 2050, which would potentially cause significant shifts in the precipitation seasonality and bring more climate extremes, such as droughts in August, increasing spring and fall floods, more freezing rains between fall and winter, and more heavy snowfalls in winter. The results from this study can help the local policy makers understand the importance and scientific implications of taking immediate carbon reduction actions and developing long-term climate adaptation plans. [ABSTRACT FROM AUTHOR]

Urban forests are gaining recognition as a nature-based solution to climate change and other social-environmental issues in cities. Yet, the integration of urban forests may conflict with other climate measures such as urban densification, which may create hostile growing conditions for trees and lead to tree decline or loss. While previous studies have identified conflicts between densification and urban forests, there is a lack of research mapping the relationships among climate action, urban planning, and urban forest policies. This study involved semi-structured interviews with 14 key informants in Metro Vancouver, Canada, a rapidly-densifying region. Twenty-six trade-offs and 24 synergies were identified in five areas/sectors, such as (re)development and infrastructure. While strategic policies often highlighted synergies, policy implementation processes and outcomes often encountered trade-offs due to factors such as limited budgets and low political priority. Notably, most trade-offs and synergies were found in the same areas - (re)development and infrastructure - and shared the same contributing factors, such as political priority of urban forestry, suggesting areas of opportunity to transform trade-offs into synergies through appropriate planning and monitoring. The study also highlighted the need for further research on the interactions and impacts among municipal policies for more effective implementation and outcomes. • The study is among the first attempts to explore policy interactions on climate action, urban planning, and urban forest. • Semi-structured interviews were conducted with key informants with relevant expertise in cities of Metro Vancouver, Canada. • Results revealed key trade-offs and synergies among policies and practices, especially in development and infrastructure. • Connections between trade-offs and synergies suggest opportunities for compact, climate-proofed, and green cities. [ABSTRACT FROM AUTHOR]

Planning and policy are best done through integrated approaches that holistically address multiple sustainability issues. Climate change and biodiversity loss are two of the most significant issues facing our planet. Accordingly, advancements in integrated sustainability planning and policy require a means for examining how certain strategies and actions may align or conflict with these sustainability imperatives. Here, we enhance the knowledge of integrated approaches for addressing sustainability challenges by developing and applying a framework for examining different planning and policy areas in the context of climate action and biodiversity conservation. As a case study, we used wildlife crossing planning and landscape connectivity policy in Canada, which is currently piecemeal, fragmented, and could benefit from an integrated approach. The study was conducted in two stages. First, we developed an analytical framework for examining issues in the context of climate action and biodiversity conservation co-benefits and trade-offs. Then, we applied the framework to wildlife crossing and landscape connectivity issues to elucidate opportunities and challenges for integrated planning and policy. We used a literature review to develop an integrated climate-biodiversity framework (ICBF). ICBF was subsequently applied to wildlife crossing and landscape connectivity planning and policies in Canada. ICBF maps relationships between climate action and biodiversity conservation co-benefits and trade-offs and is organized into six themes: green space, transportation, green infrastructure, food and agriculture, energy, and land management. Applying ICBF to participant interview data produced insights into opportunities and challenges for integrated approaches to wildlife crossing and landscape connectivity by elucidating potential co-benefits and trade-offs such as alignments between stormwater management and aquatic crossings (i.e., co-benefits) and potential issues related to energy development and habitat fragmentation (i.e., trade-offs). ICBF has application beyond wildlife crossings, and its continual use and refinement will result in a better understanding of how to effectively implement integrated approaches and transition toward sustainable development paths. [ABSTRACT FROM AUTHOR]

• Substitution factors for forest products for the Canadian context were developed. • Substitution factors ranging from 0.51 to 0.91 tC/tC were found. • They will lead to more accurate assessments of the forest GHG mitigation potential. • These factors will help governments to manage forest and fight climate change. Evaluating the climate change mitigation potential of the forest sector requires a holistic approach based on forest carbon (C) sequestration, C storage in harvested wood products (HWP) and substitution on markets. High uncertainty is associated with substitution factors, that express avoided fossil greenhouse gas (GHG) emissions from the use of forest-based products in replacement of GHG-intensive materials and fossil fuels. Few studies have focused on the development of substitution factors in Canada, resulting in the use of unrepresentative generic data. Here, we provide a framework to reduce uncertainties related to substitution factors for primary wood products in a Canadian context. A life cycle assessment framework is used to quantify fossil GHG emissions for a baseline and a wood-intensive scenario. For solid product substitution, we focused on the construction sector and analyzed a range of innovative wood buildings with steel and reinforced concrete as alternative materials. We found non-weighted averages of 0.80 tC/tC for sawnwood and 0.81 tC/tC for panels. For energy substitution, we analyzed cases with different specifications on biomass product, facility type and alternative fossil fuel source in non-residential heat production and biofuel transportation sectors. We found a non-weighted average of 0.80 tC/tC for non-residential heat production and 0.51 tC/tC for biofuel transportation, that can be interpreted as 0.91 tC/tC for heavy fuel oil, 0.69 tC/tC for light fuel oil and 0.68 tC/tC for natural gas substitution. These results provide a benchmark for substitution factors in Canada, to help guide forest management strategies for climate change mitigation. [ABSTRACT FROM AUTHOR]

Global commitments to protected area expansion should prioritize opportunities to protect climate refugia and ecosystems which store high levels of irrecoverable carbon, as key components of an effective response to biodiversity loss and climate change. The United States and Canada are responsible for one‐sixth of global greenhouse gas emissions but hold extensive natural ecosystems that store globally significant above‐ and below‐ground carbon. Canada has initiated a process of protected area network expansion in concert with efforts at reconciliation with Indigenous Peoples, and acknowledged nature‐based solutions as a key aspect of climate change mitigation. The US, although not a party to global biodiversity conventions, has recently committed to protecting 30% of its extent by 2030 and achieving the UNFCCC Paris Agreement's mitigation targets. The opportunities afforded by these dual biodiversity conservation and climate commitments require coordinated national and regional policies to ensure that new protected areas maximize biodiversity‐focused adaptation and nature‐based mitigation opportunities. We address how global commitments can best inform national policy initiatives which build on existing agency mandates for regional planning and species conservation. Previous analyses of global conservation priorities under climate change have been tenuously linked to policy contexts of individual nations and have lacked information on refugia due to limitations of globally available datasets. Comparison and synthesis of predictions from a range of recently developed refugia metrics allow such data to inform planning despite substantial uncertainty arising from contrasting model assumptions and inputs. A case study for endangered species planning for old‐forest‐associated species in the US Pacific Northwest demonstrates how regional planning can be nested hierarchically within national biodiversity‐focused adaptation and nature‐based mitigation strategies which integrate refugia, connectivity, and ecosystem carbon metrics to holistically evaluate the role of different land designations and where carbon mitigation and protection of biodiversity's resilience to climate change can be aligned. [ABSTRACT FROM AUTHOR]

Quantifying a proposed project's greenhouse gas (GHG) emissions and scrutinizing their effect on climate change are increasingly required in Canadian environmental assessment (EA) processes. This paper investigates to what degree an EA authority's intention for the inclusion of GHG considerations has resulted in implementation into environmental impact statements (EISs) by proponents and how these considerations influence the achievement of GHG reduction targets. Fifteen projects across five Canadian jurisdictions were reviewed. The examination revealed that well-developed intentions by EA authorities did not necessarily result in proponents following guidelines for GHG consideration in their EISs due to the absence of regulation or clearly defined policies. Conversely, even though intentions by an EA authority are underdeveloped in some jurisdictions, EISs sometimes exhibited thorough GHG assessments due to mechanisms in the EA process through which GHG consideration by the proponent could be compelled. The examination did not reveal how GHG consideration in EA currently assists in meeting reduction targets. A GHG emissions limit imposed during the EA process could link EA to success in meeting these targets. [ABSTRACT FROM AUTHOR]

Cities are taking a leadership role in addressing global climate change and reducing greenhouse gas (GHG) emissions, but policy innovations are needed to help cities move from goals to outcomes. Pilot projects are one means by which cities are experimenting with new ways of governing and financing climate change mitigation. In this paper, we develop a framework for understanding the role of pilot projects in urban policy innovation: their emergence and rationale, and the means by which they ultimately scale up and out to reduce GHG emissions. We use this framework to evaluate a pilot project for retrofitting social housing buildings in Toronto. We find the initial pilot project helped address the challenges of pursuing deep retrofits of social housing. Scaling these lessons up to the city level required overcoming challenges to financing and coordinating a larger project; scaling out to the provincial level revealed institutional and political obstacles to pursuing the co‐benefits of deep building retrofits in social housing. Bridging agents play an important role in both scaling processes. The analysis reveals the additive nature of urban policy innovation and the dynamic interplay of change agents and institutional and political context in innovation processes. [ABSTRACT FROM AUTHOR]

• Innovate a BaPMI method for macro-scale distributed hydrologic modeling. • Apply it to a typical large cold-region watershed, Athabasca River Basin in Canada. • Verify feasibility & advantages in characterizing macro-scale cold-region hydrology. • Quantify parametric & hyperparametric sensitivities for facilitating its applications. • Reveal variabilities of climate-driven cross-scale uppermost hydro-variational effects. At macroscales (e.g., large river basins, nations, continents, or the globe), hydro-hazard mitigation under climate change requires accurate, applicable hydrologic models, especially over cold regions of complicated hydroclimatic relations. As an effort to address such a challenge, we innovate a macroscale distributed hydro-modeling method, Bayesian principal-monotonicity inference (BaPMI), based on climate classification, representative-grids selection, statistical hydrology, surrogates-based Bayesian optimization, and variance-based sensitivity analyses. The method is applied to a typical large cold-region watershed, i.e., Athabasca River Basin in Canada, and reveals a series of findings such as the following representatives. BaPMI shows promising skills in quantitatively characterizing macroscale cold-region hydrology under overall impacts of heterogeneous climates. Bayesian optimization of which hyperparameters are insensitive decreases hydro-modeling computational time by up to 96.3% and, together with climate classification, largely enhances BaPMI applicability while ensuring modeling accuracies. Individual BaPMI hydro-model parameters can explain over ¾ of the variation of hydro-modeling accuracies and, due to their interaction, joint calibration is required for avoiding underestimation of the impacts. Climatic conditions dominating cross-scale uppermost hydrologic variations consist of night temperature (40%), day temperature (38%), and precipitation (22%) for all catchments; all river flows along the mainstem are associated with upstream climatic events such as glacier melts. Climatic impacts decline from upstream to downstream and from summer, spring, winter to autumn; this may relate to tempo-spatial heterogeneity of soil, vegetation, geology, human interference and other non-climatic factors. Without this study, macroscale distributed hydrologic modeling would lack one advanced method (i.e., BaPMI) that can immunize against effects of data uncertainty, subjective judgement and climatic collinearity, adapt to complicated hydroclimatic relations and diverse hydro-variable(s) distributions, reveal cross-scale uppermost hydrologic variations and, through inexpensive computations, enhance hydro-modeling accuracies to avoid climatic-impact underestimation. The findings of this study could facilitate BaPMI applications and advance macroscale (cold-region) hydrology. [ABSTRACT FROM AUTHOR]

Analyses of climate change and the forest sector have identified the importance of individual actors, institutions, and organizations within communities for effective adaption and climate mitigation. Yet, there remains little recognition of how the internal dynamics of these institutions and organizations are influenced by gender and other social considerations such as age and culture. Research from developing countries and cognate resource sectors suggests that these considerations are critical for enhancing local adaptive capacity. Despite extensive review of forestry research across North America and western Europe, we found almost no research that addresses how differential social capabilities within forest-based communities affect adaptation to climate change. In this paper, we document the potential that gender sensitivity might provide to conceptions and practical applications of adaptive capacity and identify four types of research opportunities to address this gap: ( i) developing disaggregated capitals frameworks; ( ii) creating inclusive models; ( iii) informing social planning; and ( iv) understanding gender mainstreaming. Research focused on these opportunities, among others, will provide more robust theoretical understanding of adaptive capacity and strategic interventions necessary for effective adaptation. [ABSTRACT FROM AUTHOR]

Global climate change is a key concern in today's world, especially with the growth of population and industrial activities. One of the biggest sources of climate change is anthropogenic greenhouse gas emissions. In Canada, buildings are the third largest emitter of greenhouse gases, contributing to 12% of the country's equivalent Carbon dioxide emissions. These emissions have various negative impacts on the planet, which impede the transition towards a cleaner environment and more sustainable communities. Attention has now shifted towards Carbon dioxide reduction in addition to the currently practiced energy efficiency improvements and source switching, which is also important in achieving Canada's 2030 climate action goals. The current study attempts to address the above gap by investigating the feasibility of installing carbon capturing unit at building level, based on the perceptions of building managers in both multi-unit residential buildings and non-residential buildings. A Modified Digital Logic approach was used to identify the key factors that determine the acceptability of the unit, based on experts' input. Six primary criteria were identified to design a questionnaire and structured interviews to evaluate the acceptability of building level carbon capturing unit to stakeholders. The findings indicated that around 50% of non-residential building managers were interested in installing the carbon capturing unit, whereas none of the multi-unit building managers were in favor of the unit installation. The lack of interest is attributed to different factors such as unit scalability, inability to accurately estimate the short and long-term economic benefits, and other alternate plans to reduce carbon dioxide emissions. Specifically, when establishing relationship between cost and unit scalability, 82% of residential unit managers and 50% of non-residential managers opined that the unit should be capable of being upgraded to accommodate a larger area and capture more emissions in order to justify the proposed cost of the unit. The findings provide important insights for policy makers in understanding the acceptability of carbon capturing unit at building level and to further develop and promote this emerging technology in the market. [Display omitted] [ABSTRACT FROM AUTHOR]

The demand for wood-based energy is foreseen to grow as energy and climate policies around the world promote the use of bioenergy for climate change mitigation. However, the carbon impacts of forest bioenergy range widely in the literature. The value-choices made on the response of forest management to bioenergy demand have a major influence on the results obtained from modeling exercises and may actually change the contribution of forest bioenergy from climate worsening to climate change mitigation. Despite their relevance, there is very little information, or transparency, as to the empirical basis by which these assumptions are chosen and evaluated against. This study aims to fill in this crucial knowledge gap through a mix of critical review, analysis of historical statistical data, and expert judgement. Several prominent studies reporting climate change mitigation from forest bioenergy in three countries are reviewed: Canada, Sweden, and Southeast USA. This analysis shows that the studies rely on assumptions that bioenergy demand will spur supply responses aimed at more efficient forest management and/or relative increases in forest area. Confronting literature assumptions with trends in historical data, we present the most extensive reality-check of bioenergy literature assumptions to date. We find that studies projecting a large role of forest bioenergy in climate change mitigation rely on assumptions that are too optimistic, at times outright unrealistic. We believe scientists could avoid the misinterpretation of their results and improve the policy relevance of their work by more transparent reporting of: i) value-laden assumptions, ii) their influence on the results, iii) the process and rationale behind such assumptions, especially distinguishing between assumptions that reflect incremental changes in management from assumptions requiring transformational change in several industrial sectors. • Accounted carbon benefits of forest bioenergy depend on underlying assumptions. • Forest bioenergy mitigates climate change only when additional biomass is produced. • Forest management responses assumed in the literature are overly optimistic. • Post Normal Science tools can help scientists avoid misinterpretation of results. • Scientists should better convey that model results are contingent on value-choices. [ABSTRACT FROM AUTHOR]