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Environmental sustainability boundaries can be used as references in evaluations of the absolute sustainability of activities and for developing policy targets and strategies. Recent literature has applied boundaries for climate change in different ways in life cycle assessment and there is a need for a systematic overview of these approaches, their compatibility with different types of assessments, and their effects on assessment results. This paper addresses that need by identifying and contrasting five approaches to operationalizing the climate change boundary and applying these approaches to a common case of the EU27 + UK consumption footprint in 2019. The identified operationalization approaches are found to be either static or dynamic. Static approaches enable comparison with a boundary which is constant through time, while dynamic approaches interpret the environmental sustainability boundary as a trajectory toward reaching net‐zero emissions at the right time. When applying the five operationalization approaches to the 2019 consumption footprint of the EU27 + UK, we find that emissions reduction should be more ambitious than the current European Green Deal targets. For policymaking, the static approaches can offer a highly ambitious ideal reference aiding immediate action but can lack adaptability to evolving conditions. Dynamic approaches better address long‐term goals and evolving knowledge but are more complex. This study contributes to the literature on absolute sustainability assessment by unravelling model choices and their implications for assessment results and policymaking. [ABSTRACT FROM AUTHOR]

Climate change is an increasingly urgent matter at the national, European, and international levels. In 2021, the European Union pledged to become the first carbon-neutral region by 2050 and to reduce its greenhouse gas emissions by 55 per cent by 2030. In the book industry, publishing associations are one of the main actors in fostering environmental sustainability. They are represented at the European level by the Federation of European Publishers (FEP). This paper focuses on drivers and opportunities for action on climate within the publishing sector, analysing responses from several senior European publishing association representatives during a series of interviews conducted in May 2022. The interviews revealed differing approaches between European publishing associations that were proactively addressing the topic (push approach) and those whose membership had yet to recognize climate change as a priority issue (pull approach). Overall, publishing associations are well positioned to engage their respective members. The final part of this article suggests some actions that publishing associations could take to help their members to address sustainability. First, to facilitate discussion, regional or international organizations such as FEP or the International Publishers Association could provide support to frame the wider context. Secondly, all climate-related actions in the publishing sector should be concrete, such as implementing carbon calculators or reimagining a more eco-friendly book fair. Finally, the article emphasizes the reputational risk for associations that do not take a position on the issue, and the increasing pressure that could come from the media and the regulatory environment, and suggests a more consistent approach and communication strategy. [ABSTRACT FROM AUTHOR]

The cement industry plays a significant role in global carbon emissions, underscoring the urgent need for measures to transition it toward a net-zero carbon footprint. This paper presents a detailed plan to this end, examining the current state of the cement sector, its carbon output, and the imperative for emission reduction. It delves into various low-CO 2 technologies and emerging innovations such as alkali-activated cements, calcium looping, electrification, and bio-inspired materials. Economic and policy factors, including cost assessments and governmental regulations, are considered alongside challenges and potential solutions. Concluding with future prospects, the paper offers recommendations for policymakers, industry players, and researchers, highlighting the roadmap's critical role in achieving a carbon-neutral cement sector. • Cement industry faces urgent need for net-zero transition due to high carbon emissions. • Roadmap spans phases: foundation, acceleration, net-zero, targeting emissions by 2050. • Innovations like alkali-activated cements offer promise for emission reduction. • Collective action and policy crucial for sustainable transformation of cement sector. [ABSTRACT FROM AUTHOR]

Green buildings have gained increasing relevance and market share in recent decades. Also, higher education institutions are progressively incorporating the conceptualisation of sustainable development by greening campuses. Thus, given the construction sector relevance in climate change mitigation and the role universities have to play as models for society, the purpose of the present paper is twofold. First, the authors develop a baseline study to determine the extent to which green buildings' features and certifications are being incorporated in public Chilean higher education institutions, as a first of its kind effort in the higher education sector in Chile. Second, the authors explore the opportunities that can support the advancement of campus greening through green buildings deployment on university campuses in Chile. This study follows a qualitative strategy approach in the form of a survey design based on the UI GreenMetric World University Ranking that was administered through an online questionnaire to representatives who hold the position of Sustainability or Infrastructure Heads in public universities, which are united in the Chilean State Universities Consortium. The main findings suggest a general maturation process of green building features´ incorporation on campuses at Chilean public higher education institutions in early or transitional stages. The leading indicators relate to open space, pedestrian paths, and efficient appliances, whereas the reported performance is lower with respect to sustainability budget, zero emission vehicles, and greenhouse gas emission reduction programmes. The opportunities identified for promoting the implementation of green buildings relate to three entrenched dimensions: research, promotion, and public policy. [ABSTRACT FROM AUTHOR]

Roads play a vital role in transportation systems, and their construction and maintenance expenses are high. Those reasons make crucial the examination of factors that accelerate road deterioration and those factors' negative impacts on societies. Climatic-related elements, especially temperature and precipitation, significantly affect the quality and lifespans of roads. The Intergovernmental Panel on Climate Change has reported that increasing greenhouse gas (GHG) emissions is causing changes in climate and that the rate of change has accelerated during the past several decades. To assess the impacts of changing climatic parameters on flexible-pavement performance, this study used 32 climate models to evaluate the performance of interstate, primary, and secondary roads across 11 diverse locations with varying traffic and climatic conditions. The study's findings reveal that changing climate exacerbates pavement distresses, leading to reduced pavement lifespans and increased numbers of reconstruction projects, which in turn raise demands for materials and equipment and contribute to higher GHG emissions. The effects of changing climate and changing climate's associated economic and environmental costs make the application of various engineering solutions to enhance pavement resilience essential, as described in this paper, in the absence of comprehensive emissions reduction strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Maximising resource‐use efficiency, productivity and environmental sustainability are all fundamental requirements to raise global food production by ~70 per cent in order to feed a world population of ~9.7 billion people by 2050. Perhaps the most vital resource within our capacity to achieve this goal is our soil. Broadly, the fundamental question concerns whether or not satisfying this production demand will accelerate soil degradation, climate change, and the loss of soil carbon stocks. This paper builds upon the outputs of the UK Charity 'Food & Farming Futures' (chaired by Lord Curry of Kirkharle) virtual workshop held on 23 March 2021, entitled 'Capturing the Potential of Soil'. The event focussed on the link between soil health, primarily soil organic carbon (SOC), and agricultural productivity. Supported with commentaries by Professor Pete Smith (University of Aberdeen and Science Director of the Scottish Climate Change Centre of Expertise) and Professor Steve McGrath (Head of Sustainable Agricultural Sciences at Rothamsted Research), specific focus will be given to the research challenges within the UK's ability to improve soil health and functionality, the implementation priorities that must be held in order to improve soil management by 2050 and what the potential co‐benefits could be. These co‐benefits were scattered across environmental, economic, social and political issues, yet they may be summarised into six primary co‐benefits: developing natural capital, climate change mitigation, carbon trading, improvements in crop yield, animal performance and human health (nutrition). Additionally, the main barriers to improved soil management practices are centred on knowledge exchange‐regarding agri‐environmental techniques—whilst the most impactful solutions rely on soil monitoring, reporting and verification. [ABSTRACT FROM AUTHOR]

This study explores the impact of political uncertainty on sustainable urban development by examining carbon emission trading systems (ETS) in four major markets in China (Beijing, Shanghai, Guangdong, and Hubei) from 2014 to 2022. As an alternative to carbon taxes, carbon ETS markets have become increasingly popular due to their success in reducing greenhouse gas emissions. However, their effectiveness is often hindered by political instability and uncertainty. Utilising logistic regression and AR(1)-GARCH estimations, we identify a negative relationship between political uncertainty and carbon trading volume. Our study also reveals significant variations in the responses of these markets to political uncertainty. The paper contributes to the understanding of how ETS markets operate in a complex and constantly changing political environment. We suggest that policymakers need to consider the impact of political uncertainty on carbon trading when designing and implementing urban policies that promote sustainable development. Additionally, our research contributes to the development of urban policies that can be effectively implemented in both developed and developing regions. • Local government official turnovers are used as the measurement of political uncertainty. • Daily transaction data from four carbon ETS markets (Beijing, Shanghai, Hubei and Guangdong) in China • Considered the probability and proportion of zero transaction day • Logistic regression and AR(1)-GARCH estimations • A negative relationship between political uncertainty and carbon transaction volume [ABSTRACT FROM AUTHOR]

This paper clarifies the competing discourses of sustainability and climate change and examines the manifestation of these discourses in local government planning. Despite the increasingly significant role of sustainability and climate change response in urban governance, it is unclear whether local governments are constructing different discourses that may result in conflicting approaches to policy-making. Using a governmentality approach, this paper dissects the contents of 15 Canadian local governments' sustainability plans. The findings show that there are synergies and tensions between discourses of sustainability and climate change. Both share discursive space and shape local governance rationalities, though climate change response logics are not necessarily highlighted even where the action could result in greenhouse gas (GHG) emission reductions. In some cases, existing GHG intensive practices are being rebranded as 'sustainable'. This suggests a tension between discourses of sustainability and climate change that may complicate attempts to address climate change through local sustainability planning. [ABSTRACT FROM AUTHOR]

Abstract The use of biomass for production of chemicals is gaining interest because of its potential to contribute towards a reduction in greenhouse gas emissions and other environmental benefits linked to the substitution of fossil resources. But, conversely to biofuels, studies focusing on environmental impacts of biomass-derived chemicals are scarce. This paper uses life cycle assessment to evaluate the environmental sustainability of bio-ethylene from poplar produced by the following three thermo-chemical routes: direct and indirect dehydration of ethanol and production of olefins via dimethyl ether. The indirect route is the best option for most impact categories for all three allocation methods considered: system expansion, economic and energy basis. However, the dimethyl ether-to-olefins route has the lowest global warming potential. In comparison to ethylene produced bio-chemically from sugar beet, the thermo-chemical indirect route has lower impacts for all categories except human, terrestrial and freshwater toxicities. All three thermo-chemical alternatives show a significant reduction in global warming potential (up to 105% in the case of dimethyl ether-to-olefins) and depletion of fossil fuels when compared to conventional ethylene production from fossil fuels. However, the results also suggest that bio-ethylene produced by any of the three thermo-chemical routes would lead to a significant increase in most other impact categories relative to fossil fuels. Therefore, while trying to reduce greenhouse gas emissions, the overall environmental sustainability of bio-ethylene suffers from the increase in other environmental impacts. Highlights • Three thermo-chemical bio-ethylene processes are compared environmentally. • Indirect route is best for several impacts but the dimethyl ether is better for GWP. • Indirect route is better than 1st generation ethanol dehydration except for toxicities. • Net saving in GHG emissions of 44%–105% achieved compared to fossil alternatives. • However, other impacts are higher than for the fossil alternatives. [ABSTRACT FROM AUTHOR]

The paper explores the economic feasibility and environmental sustainability of producing second-generation biofuel in Italy from Brassica carinata, a non-edible flowering plant of the Brassicaceae family, in a context of rotation with wheat (and eventually other crops). The framework considered allows to rule out issues of ILUC and is highly relevant in a country where extensive monoculture is extremely widespread and there is a high degree of dependence on foreign imports for both biofuels and biofuels-related raw materials, especially from countries such as Indonesia, where the adverse impacts of first-generation biofuel production on the environment are most felt. Using yield and cost data from 5 experimental fields in Italy and taking into account potential returns from the sale of biodiesel and its by-products, glycerine and expeller/meal, the economic sustainability of the entire biodiesel production chain (cultivation, oil extraction and oil refining) is established. Implementation of the Argonne National Laboratory's GREET life cycle model, suitably adjusted so as to apply it to the BC case, confirms also a high environmental sustainability. The range of positive economic effects and externalities that may be triggered by the development of a BC-derived biofuel production chain justifies some form of policy intervention. [ABSTRACT FROM AUTHOR]

Cities are mainly responsible for greenhouse gas (GHG) emissions in the atmosphere and thus for climate change. The European Union (EU) set up a series of strategies and policies to facilitate the elaboration of climate change mitigation and adaptation of urban plans. To do this, it is necessary to measure the city's GHG emission level. The Urban Carbon Footprint (UCF) and its derivation, the Relative Carbon Footprint (RCF), represent the most appropriate tools for obtaining this important information. The present paper applies these indicators to a small city (150 000 inhabitants) located in Southern Italy, a novelty for academic studies, which usually concentrate on megacities. The study focuses only on CO 2 emissions, as these represent 90% of the total GHGs released in urban areas. The findings showed that in 2015 the total UCF was equal to 288 ktCO 2 , specifically deriving from electricity and natural gas consumption. Moreover, Residential, Industry and Tertiary are the most carbon-intensive economic sectors. The RCF was equal to 0.30; the city emission levels were lower than the national average. Therefore, the municipality represents a typical “net-consumer” community, dominated by homes with territorial emissions due to consumption and characterized by a low number of industries and an average income per capita that is 50% lower than the national one. Starting from these results, the study proposed an urban action plan according to the EU mitigation and adaptation policies. This plan could help the local government improve its environmental sustainability, even if more public city-level data is required for a more comprehensive analysis. Finally, it would be more appropriate for all actions to be aligned under a unique policy process to seize the opportunity to link the various local intervention policies from different fields, taking into account their existing funding, tools, processes, and resources. Capitalizing on the adaptation/mitigation connection will allow municipalities to leverage their climate change action efforts and accelerate progress toward their climate and energy goals. [ABSTRACT FROM AUTHOR]

Climate change is one of the main threats of the modern society. This phenomenon is associated with the increase of the greenhouse gases (GHGs, mainly carbon dioxide – CO 2 ) emissions due to anthropogenic activities. Main causes are the burning of fossil fuels and land use change (deforestation). Climate change impacts are associated with risks to basic needs (health, food security and clean water) as well as risks to development (jobs, economic growth and the cost of living). Taking into account this phenomenon, several countries participated in the last United Nations Climate Change Conference in Paris (21st Conference of the Parties – COP21) and agreed to reduce their GHG emissions to limit the rise in global temperature to less than 2 °C. Main commitments and actions are focused in energy efficiency, renewable energy deployment and forest protection (increasing the CO 2 natural sinks). In this context, biofuels (from non-edible feedstocks) have the potential to replace fossil based fuels in the transport sector, being a carbon-neutral fuel. In particular, algae–based biofuel can play a dual role in this scenario: as photosynthetic organisms, algae can capture CO 2 from industrial emissions or from atmosphere and the resulting biomass can be used to produce a wide range of materials including biofuels. Therefore, this paper reviews the research advances of algae cultures with focus on the applications (CO 2 capture and bioenergy production) related to the targets of COP21 agreement. Main recent advances in algal research studies and projects are also presented. [ABSTRACT FROM AUTHOR]

Purpose – This paper aims to report on the results of a case study in Botswana, aimed at raising awareness on climate issues. Higher-education institutions play a leading role in sustainability efforts, as their research role often lays the groundwork for social transformation. Design/methodology/approach – The Clean Air-Cool Planet (CACP) campus calculator was used to calculate emissions from various sections within the college. Findings – Total greenhouse gas (GHG) emissions from the college is 3,432.66 metric tons CO2e resulting in per capita GHG emissions of 3.20 metric tons CO2e, which is high compared to other universities. Options for reducing emissions are proposed. Practical implications – The procedure in carrying out the study provided learners with an opportunity to appreciate emissions from developing countries and also gain technical skills in conducting a GHG inventory. It also sensitized campus administrators about the scale of emissions and possible ways of reducing them. Originality/value – This paper is original in that it provides campus greenhouse inventory within a developing country, a unique undertaking. Furthermore, it highlights the fact that developing countries also produce significant emissions, hence the need for mitigation measures. [ABSTRACT FROM AUTHOR]

The United Nations Framework Convention on Climate Change (UNFCCC) sets an overall framework for intergovernmental efforts to tackle the challenge posed by climate change. Besides the “flexibility mechanisms” defined by the Kyoto Protocol to lower the overall costs of achieving their emissions targets, The Voluntary Green House Gases (GHG) reduction projects can have a lead role in GHG reduction in “non Emissions Trading System ETS sectors”. Nowadays, the voluntary market is characterised by critical aspects, such as fragmentation, lack of accounting, monitoring and validation rules that have led to the low spread of voluntary emission reduction projects developed by local authorities in the European Union despite their high potentiality. The aim of this paper is to test the applicability of voluntary emission reduction projects in the public sector following a homogeneous and consistent pattern. A research has been performed at local level on 143 voluntary emission reduction projects implemented by Public Administrations in Northern and Central Italy in renewable energy, energy efficiency and transport sectors. The applicable standards and methodologies have been checked and the case studies have been analysed though a three-step process: Preliminary additionality assessment; Projects selection; Validation of the selected project. The assessment shows that energy efficiency projects, once overcoming additionality issues, are the most promising for public entities while renewable energy and transport projects resulted to be mainly affected by double counting problems and lack of reliable methodologies. [ABSTRACT FROM AUTHOR]

The third sentence in the Abstract should read: A transition to WFPB diets will mitigate against these impacts and potentially reduce agriculture greenhouse gas emissions by up to 80%. Keywords: Plant-based diet; climate change; sustainability; diet; mental health EN Plant-based diet climate change sustainability diet mental health 108 108 1 11/02/22 20221101 NES 221101 The authors would like to make two corrections to the above paper. Climate change, sustainability, diet, mental health, Plant-based diet. [Extracted from the article]

Climate change and its consequences present one of the most important threats to biodiversity and the functions of ecosystems. The stress on biodiversity is far beyond the levels imposed by the natural global climatic changes occurring in the recent evolutionary past. It includes temperature increases, shifts of climate zones, melting of snow and ice, sea level rise, droughts, floods, and other extreme weather events. Natural systems are vulnerable to such changes due to their limited adaptive capacity. Based on an analysis using the DPSIR framework, this paper discusses some of the important socio-economic driving forces of climate change, with a focus on energy use and transportation. The paper also analyses observed and potential changes of climate and the pressures they exert on biodiversity, the changes in biodiversity, the resulting impacts on ecosystem functions, and possible policy responses. The latter can be divided into mitigation and adaptation measures. Both strategies are needed, mitigation in order to stabilise the greenhouse gas concentrations in the atmosphere, and adaptation in order to adjust to changes that have already occurred or cannot be avoided. One mitigation option, increased biofuel production, which is also a response to oil depletion, would change land use patterns and increase human appropriation of net primary production of biomass, thereby threatening biodiversity. By considering the first order and second order impacts of climate change on biodiversity when developing policy measures, it will be possible to integrate ecosystem and biodiversity protection into decision-making processes. [Copyright &y& Elsevier]

This paper provides a critical review of the concept of "carbon neutrality" for tourism destinations within the framework of the UNWTO's Davos Declaration, a document ascribing responsibilities to various actors in the tourism industry to engage in greenhouse gas emission reductions. The paper assesses the planning frameworks of countries engaging with the concept, discusses the measures that can be taken to achieve "carbon neutrality", along with an evaluation of some of the theoretical and practical implications. An increasing number of destinations now plan to become "carbon neutral", often as a response strategy to pressure on the tourism industry to reduce its emissions of greenhouse gases. They aim to mitigate their contribution to global warming, and to develop their tourism industries by enhancing their image as being environmentally pristine and sustainable. [ABSTRACT FROM AUTHOR]

In the European Union, the share of renewable energy has increased significantly over the past few years. Among renewable energy options, bioenergy is considered to be the dominant energy source. Previous literature is inconclusive regarding the suitability of bioenergy to mitigate greenhouse gases. The goal of this paper is to address this research gap. Life Cycle Assessments (LCAs) of biomass systems for electricity generation were gathered via a systematic literature review and form the empirical basis of this study. A quantitative exploratory analysis and a Qualitative Comparative Analysis were carried out to identify the greenhouse gas mitigation potential of different biomass systems used for electricity generation. Significant variations in LCA results are due to the heterogeneity of these systems; therefore, the transferability of LCA results to similar systems must be investigated on a case-by-case basis. Results show that electricity from biomass can be an appropriate measure for greenhouse gas mitigation in the European Union. To mitigate greenhouse gases, it is recommended to promote the employment of (1) non-dedicated lignocellulosic biomass with thermochemical conversion, (2) dedicated lignocellulosic biomass with thermochemical conversion, and (3) dedicated lignocellulosic biomass with direct combustion. For a more holistic assessment, future research should focus not only on greenhouse gas emissions, but also on other environmental, economic, and social impact categories. [ABSTRACT FROM AUTHOR]

Tourism results in the emission of climate-changing greenhouse gases. There has been limited destination-focused quantitative analysis of how tourism might be reshaped to reduce these emissions. This paper uses an extended tourism environmental satellite account methodology to examine the case of tourism in Wales, a United Kingdom region. It shows how an estimate of the emissions associated with trips to, and in, the region – internally, from the rest of the UK and from abroad – can contribute to regional aspirations to reduce greenhouse gas emissions. The analysis suggests that substantial emissions cuts are dependent upon technical developments outside of tourism itself. Four potential scenarios are devised and analysed. Scenario 1 shows the value of low carbon electricity production in cutting tourism-related emissions. Scenario 2 analyses a possible 50% fall in international arrivals and 10% increase in UK domestic arrivals – maintaining employment but reducing emissions. Scenario 3 shows the effects of switch from private to public transport modes for 50% of UK resident arrivals. Scenario 4 examines the outcomes of reducing ground transport emissions by using electric, biofuel and hybrid technologies. All scenarios cut emissions, none are highly effective and most are dependent on changes in society and governance. [ABSTRACT FROM AUTHOR]

Estimation of emissions of greenhouse gases (GHG) is becoming an established part of assessing sustainability within environmental impact assessment (EIA). However, a comparative study of 25 environmental impact statements (EISs) to analyse the practice of accounting for emissions during the EIA process suggests that consideration of the effects of development on emissions of GHG is poorly understood. The extent to which assessment is actually carried out is also inconsistent and sporadically implemented. A key indicator appears to be the varying and sometimes contradictory use of technical terminology, particularly of the term ‘carbon’ and its similar phraseology. This paper provides a critical evaluation of the differing terminology that is applied to GHG assessments undertaken as part of EIA process and explores the effect that misuse of these terms could have on an impact EIS. [ABSTRACT FROM PUBLISHER]

Abstract: Energy and climate change is a key priority issue mentioned by the Mediterranean Strategy for Sustainable Development (MSSD) which explicitly claims that “Control, reduce or stabilize GhG (Greenhouse Gas) emissions” is a crucial target for Mediterranean countries. This paper uses the integrated assessment model IFs (International Futures) to implement a scenario analysis to investigate the mitigation potential of Mediterranean regions. It analyzes if the Mediterranean regions will be able to reach the MSSD climate change target and recommends amendments of the MSSD to implement with effectiveness climate change policies in the Mediterranean area. [Copyright &y& Elsevier]

Abstract: Facing climate change and growing energy prices, the use of bioenergy is continuously increasing in order to diminish greenhouse gas emissions, secure energy supply and create employment in rural areas. Because the production of biomass or biofuels, wherever it takes place, comes along with externalities, positive or negative, the need for biomass and bioenergy sustainability criteria is more than ever felt. Research on sustainability criteria and certification systems has started through several national and international initiatives. Considering the benefits of an increased use of bioenergy but also the urge for limiting potential negative environmental and socio-economic impacts, the aim of these initiatives was to make the first move regarding bioenergy sustainability, while waiting for the European legislation to regulate this crucial issue. Land use changes, whether direct or indirect, are one of the most important consequences of bioenergy production. While direct land use changes are more easily assessed locally, indirect land use changes exceed the company level and need to be considered at a global scale. Methodologies for dealing with direct and indirect land use changes are proposed among others in the European, Dutch, British and German sustainability initiatives. This paper aims at presenting and comparing those four European initiatives, with a focus on their propositions for direct and indirect land use changes assessment. Key issues are discussed and recommendations are made for steps to overcome identified difficulties in accurately assessing the effects of indirect land use change due to bioenergy production. [Copyright &y& Elsevier]

Abstract: Biofuels are promoted in many parts of the world. However, concern of environmental and social problems have grown due to increased production of biofuels. Therefore, many initiatives for sustainability criteria have been announced. As a part of the European Union (EU) renewable energy promotion directive (RED), the EU has introduced greenhouse gas (GHG) emission-saving requirements for biofuels along with the first-ever mandate methodology to calculate the GHG emission reduction. As explored in this paper, the RED methodology, based on life-cycle assessment (LCA) approach, excludes many critical issues. These include indirect impacts due to competition for land, biomass and other auxiliary inputs. Also, timing issues, allocation problems, and uncertainty of individual parameters are not yet considered adequately. Moreover, the default values provided in the RED for the GHG balances of biofuels may significantly underestimate their actual impacts. We conclude that the RED methodology cannot ensure the intended GHG emission reductions of biofuels. Instead, a more comprehensive approach is required along with additional data and indicators. Even if it may be very difficult to verify the GHG emission reductions of biofuels in practice, it is necessary to consider the uncertainties more closely, in order to mitigate climate change effectively. [Copyright &y& Elsevier]