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The pressure on reducing greenhouse gas emissions has increased since the focus on climate change mitigation has grown. As the human development index is directly related to per capita energy consumption, sustainable energy production with reduced carbon footprint is the essential pathway for cleaner environment. Over numerous existing biological processes, hydrogen production via photo fermentation and photolysis of water is considered a more sustainable and economical method of hydrogen production. While both biological modes suffer from certain limitations, such as low yields and low production rates, practical implementation is still a long way off due to these limitations. The unique properties of nanomaterials (NMs) can help increase the efficiency of the biomass to biohydrogen process in significant ways. Applications of organic and inorganic nanoparticles in photocatalytic and photo fermentative hydrogen production is discussed in this paper. This review reports a wide range of applications of nanomaterials including the details of photo fermentative microorganisms and their mechanism of action. The maximum photo fermentative bio-H 2 production was reported in the presence of SiC–Fe 3 O 4 (3.02 mol H 2 /mol acetate), Ni (41 mol H 2 /mol sugar), graphite-C 3 N 4 (64.2 mol H 2 /mol sugar) whereas photocatalytic bio-H 2 yield was highest when Pd–Ni/CdS (54 mmol/g.h), Ni-MO/g-C 3 N 4 (1785 mmol/g.h) and CuO/TiO 2 (20.3 mmol/g.h) nanoparticles were employed. To design photocatalytic systems for practical and scalable use, the future research should be focused on deeper theoretical knowledge of mechanisms of light harvesting, ± charge separation and transport, surface biochemical reactions, semiconductor–liquid interactions, and reactor dynamics. [Display omitted] • Recent developments for improving water photolysis and photo-fermentation are reviewed. • Applications of organic and inorganic nanoparticles in hydrogen production are discussed. • The working principle and mechanism of hydrogen production are discussed. • The influence of key operating factors are presented. • Scope for future research was presented. [ABSTRACT FROM AUTHOR]

This paper investigates the viability of environmental taxes as a means to mitigate greenhouse gas emissions within the European Union (EU) using the panel threshold model on two balanced panel data comprising countries from the European Union: the Northern and Western countries and Southern and Eastern countries for the period 2000–2020. The study's empirical results support the Pigouvian theory for developed countries, as they indicate an optimal minimum threshold for environmental taxes, where these taxes effectively contribute to reducing greenhouse gas emissions. However, the results diverge for emerging countries, revealing a maximum threshold for environmental taxes beyond which their impact in curbing emissions diminishes. To achieve the ambitious goal of climate neutrality, policymakers must adopt a comprehensive and diversified approach. This includes a combination of environmental taxes, more stringent regulations, and emission standards for industries. Additionally, the implementation of carbon pricing mechanisms, promotion of investments in sustainable fuels and technologies, and the establishment of low-carbon emission infrastructure are essential components of this strategy. By integrating these various measures, policymakers can better navigate the path toward climate neutrality and effectively combat climate change in the EU and beyond. [ABSTRACT FROM AUTHOR]

Deep decarbonization of the transport sector in small island developing states (SIDS) can simultaneously address issues of energy security, high fuel import prices, and climate change mitigation measures while ensuring a reduction in air pollution and higher levels of wellbeing for citizens. Electrification plays a vital role in the decarbonization process. Here, we investigate potential transition pathways towards electrification, taking the public transportation system in Mauritius as an example, where there is vast potential in electrifying the old and overburdened bus system. We simulate a variety of public bus turnover scenarios, considering initial costs of investments, energy and fuel requirements, and reductions in greenhouse gas emissions. We demonstrate that optimized investment into electrifying public transit pays off, with annualized investments of about $5 million superseded by annual savings on fossil fuel imports of about $15 million. We suggest that international donors can accelerate this transition by providing loan guarantees and, by this, reducing the cost of capital. • Public fleet electrification is a straightforward yet widely beneficial approach. • We present a framework for comparing investment costs, energy and fuel requirements and emission reductions. • Investing in large-scale sustainable projects requires substantial amounts of upfront financing. • Optimized investment into electrification proves beneficial due to savings on fossil fuel imports. • A rethinking of global funding mechanisms can provide a way forward in addressing these barriers. [ABSTRACT FROM AUTHOR]

Since the early 2000′s when discussions started around the concept of REDD+ , numerous studies estimated the opportunity costs often implicitly viewed as proxies for the total costs of avoided deforestation. We reviewed their methods and the stated objectives to assess their alignment, suitability and robustness. We found a lack of correspondence between methods and objectives, which include setting compensation levels, identifying cost-efficient activities, or assessing financial viability with respect to carbon markets. While the search for perfect accuracy is a fallacy, some major mistakes must be avoided, e.g. equating the costs of avoided deforestation to opportunity costs or including an inappropriate group of economic agents in the calculations. Best practises must be followed to ensure that estimations properly inform intervention design, decisions and policies; they refer to methods applied and their suitability for related decisions. They include: the need to first define objectives and then adapt methods because estimations can be done variously with contrasted results; to cautiously determine the scope - which stakeholders and stages of value chain are considered - while prioritising the broad picture and avoiding getting lost in estimation details; to discuss sensitivity of results and recognise uncertainties; and to consider the implications of scale in the study design. Given the urgency to preserve natural forest and mitigate climate change in the most cost-effective way, we believe that our analysis and its recommendations are a step in this direction with expected increased emissions reductions due to improved interventions. • Opportunity costs are essential for allocation of avoided deforestation funding. • Review shows shortcomings in methods used and lack of their justification. • Most important is to align methods with objectives and define relevant scope. • A few best practices are discussed to avoid major mistakes. • We provide guidance to orient future studies with reasonable methodological choices. [ABSTRACT FROM AUTHOR]

Air pollution control policies in China have been experiencing profound changes, highlighting a strategic transformation from total pollutant emission control to air quality improvement, along with the shifting targets starting from acid rain and NO x emissions to PM 2.5 pollution, and then the emerging O 3 challenges. The marvelous achievements have been made with the dramatic decrease of SO 2 emission and fundamental improvement of PM 2.5 concentration. Despite these achievements, China has proposed Beautiful China target through 2035 and the goal of 2030 carbon peak and 2060 carbon neutrality, which impose stricter requirements on air quality and synergistic mitigation with Greenhouse Gas (GHG) emissions. Against this background, an integrated multi-objective and multi-benefit roadmap is required to provide decision support for China's long-term air quality improvement strategy. This paper systematically reviews the technical system for developing the air quality improvement roadmap, which was integrated from the research output of China's National Key R&D Program for Research on Atmospheric Pollution Factors and Control Technologies (hereafter Special NKP), covering mid- and long-term air quality target setting techniques, quantitative analysis techniques for emission reduction targets corresponding to air quality targets, and pathway optimization techniques for realizing reduction targets. The experience and lessons derived from the reviews have implications for the reformation of China's air quality improvement roadmap in facing challenges of synergistic mitigation of PM 2.5 and O 3 , and the coupling with climate change mitigation. [Display omitted] [ABSTRACT FROM AUTHOR]

The concept of net-zero, climate-neutral buildings is attracting global attention, and it is widely recognised as a key solution for achieving climate neutrality targets in the construction sector. However, an increasing and confusing abundance of differing labels, definitions, and approaches is increasing worldwide. This article aims to chart the current progress of national net-zero building pathways and identify gaps and challenges that present a significant barrier to industry uptake and decarbonisation of the built environment worldwide. The national net-zero pathways include an analysis of building legislation, policy and voluntary frameworks in four selected countries, Norway, the United Kingdom, the United States and Singapore, which are all leading regional actors in the race to zero and achieving a climate-neutral construction sector. Firstly, the study provides an overview of each country-specific context and motivation related to climate change adaptation and mitigation in the construction sector. Secondly, a review of the essential features from market-leading net-zero definitions, methodologies, schemes, and tools describing specific building approaches is conducted in each investigated country. Finally, based on the selected net-zero building case studies, the article presents the most promising design strategies for both embodied and operational environmental impact reductions, considering each specific climatic and country context. The research results indicated that the system boundaries for embodied and operational indicators (energy or GHG emissions) presented in investigated net-zero frameworks vary significantly. Consequently, there is an urgent need for a harmonised and transparent standardisation to provide coherence through performed life cycle assessments of buildings. In terms of the design strategies for achieving net-zero ambition according to the investigated frameworks, the common approach is the integration of the passive and active design strategies for operational energy or GHG emission reduction. However, it is evident that in some net-zero building examples, the consideration of the embodied environmental impacts and potential reduction strategies is missing because of not being included and mandatory in the national net-zero framework. This work is built upon the current body of knowledge on existing net-zero building frameworks and already constructed buildings and provides practical indications for building policy development and environmental impact reduction strategies in future climate-neutral, net-zero building projects. • A review of the net-zero building frameworks in Norway, the United Kingdom, the United States and Singapore is presented. • Examines design strategies for embodied and operational environmental impact reductions based on net-zero building cases. • System boundaries and compensation options vary significantly among analysed net-zero frameworks. • Integrating climate mitigation measures with resilience design strategies is missing in the current net-zero frameworks. [ABSTRACT FROM AUTHOR]

Since 2019, China has emerged as a leading proponent of nature-based solutions (NbS) to improve global environmental management. These solutions – from regrowing forests to restoring wetlands to regenerating agricultural soils to greening cities – can, at least in theory, simultaneously reduce greenhouse gas emissions, protect biodiversity, and enhance community wellbeing and resilience. For some advocates, nature-based solutions also entail a radical rethinking of how humans should be interacting with nature, requiring new responsibilities, rights, and governance mechanisms. This article explains how and why China has been promoting NbS in multilateral and domestic policy settings. By analyzing the content of English- and Chinese-language policy briefings, diplomatic remarks, and government documents from 2019 to mid-2021, it reveals that China's NbS goals and actions differ significantly in domestic and international settings. Internationally, Chinese policymakers have been reframing the country's pre-existing large-scale afforestation, green financing, disaster risk reduction, and ecotourism projects as NbS, broadly defined. In multilateral forums, meanwhile, Chinese diplomats and practitioners are promoting NbS as an umbrella term to enhance the legitimacy of domestic projects now labelled as NbS, project an image of climate action and global environmental leadership, and increase China's discursive power within global environmental governance. China's embrace of NbS, as this article reveals, has far-reaching consequences for the future of nature-based solutions within multilateral climate and biodiversity governance, with the potential to turn NbS into a diplomatic and rhetorical tool to portray conventional approaches to environmental management as innovative, nature-positive solutions. • Internationally, China is reframing pre-existing policies as nature-based solutions (NbS). • What China is labelling NbS includes large-scale afforestation, green financing, flood controls, and ecotourism projects. • Internationally, China is advocating for NbS to enhance its image and soft power. • China's NbS discourse is mainly aimed at an international audience, with domestic policy and rhetoric largely unchanged. • China's NbS leadership could further mainstream NbS discourses in multilateral forums, but hinder meaningful implementation. [ABSTRACT FROM AUTHOR]

Air pollution control measures play a crucial role in reducing air pollution and climate change, but researches on co-benefits of Total Control of Major Air Pollutants (TCMAP) in China is limited. This study quantifies synergistic benefits of TCMAP in reducing pollutant and carbon emissions by constructing a project-level emission reduction database, and further modelling safeguard strategy of emission reduction to achieve dual carbon target. Results revealed that TCMAP has facilitated a shift in the focus of air pollutant management from energy restructuring to deeper industrial and transportation restructuring. Synergistic benefits of TCMAP surpassed Carbon dioxide (CO 2) emissions from end-of-pipe treatment measures. As a result of rigorous implementation of TCMAP, approximately 0.12 GtCO 2 emissions were projected to be avoided in 2022. Synergistic reductions of 5,161 kt pollutants need to be achieved by 2030, and this commitment should be further strengthened to achieve 11,352 kt pollutants by 2060 to achieve dual-carbon target. [Display omitted] • Atmospheric control turned to transportation and industrial structure adjustment. • TCMAP pathway achieved synergistic carbon reduction 0.12 GtCO 2 in 2022. • Synergistic benefits of TCMAP far outweigh the end-treat measures that produce CO 2. • More ambitious TCMAP target safeguards needed for climate change mitigation. [ABSTRACT FROM AUTHOR]

There is urgent need for the transformation of built environments to tackle climate change. The reduction of greenhouse gas emissions to achieve the Paris Agreement goal of limiting warming to well below 2 °C is of paramount importance, as is planning for future climate change risks. Architects, as designers of the built environment hold an important role in advocating and enabling the necessary mitigation and adaptation actions required in the design and construction of new buildings, and the reuse of existing built fabric – to reduced embodied carbon and achieve operational energy efficiency. Despite the importance, most built environments do not yet adequately address climate change. Limited research has examined the barriers that architectural professionals encounter when integrating climate change action in their projects during their role designing built environments. This is the gap that this research addresses. Interviews with twenty-two Australian architectural practitioners were undertaken, to investigate their experience of barriers to and facilitators of climate change action in their professional practice. Four key themes were found: 1) actors, 2) processes and structures, 3) information and knowledge, and 4) the role of government. Barriers and facilitators were found to be embedded in architects' perception of their role, the processes and practices they undertake, and their relationship with other stakeholders. The facilitators identified can assist drive better outcomes for future design and construction of buildings. Recommendations identified include: 1) build architects' confidence and capability to be advocates; 2) develop of architects' climate change knowledge and competence; 3) transform design processes to be more circular, interdisciplinary and long term focused, and 4) reform current built environment policy to adequately consider climate change. [Display omitted] • Architects are crucial to achieving climate change action, but there is limited information on how to achieve this. • This study interviewed Australian architects about the barriers and facilitators they face to climate change action. • Key barriers for architects to enable change include limited influence, reach and decision-making capabilities. • Barriers and facilitators to climate action are influenced by both internal and external factors. • Identifies initiatives to facilitate climate change action: building knowledge and capacity, and transforming design processes. [ABSTRACT FROM AUTHOR]

In this study, a stepwise clustered ensemble temperature downscaling (SCETD) model has been proposed based on a stepwise cluster analysis method (SCA) and used for the first time to study the extreme temperature variations at 12 stations in the Yangtze River Basin (YRB). The results show that the proposed model can be used to generate reliable forecasts of daily maximum, minimum, and mean temperatures based on CMIP6 data (R 2 > 0.96). Temperatures in the Yangtze River Basin are likely to maintain a significant upward trend (Tmean is 0.082–0.23 °C/decade under SSP245 and 0.094–0.46 °C/decade under SSP585) in the future. In terms of extreme temperature events, extreme warm events may happen more frequently and extreme cold events to decrease in the future under SSP245 and SSP585. A more significant increase of FD and TNn can be observed in the Qinghai-Tibet Plateau region, while the TXx and SU will grow more considerably in the central Yangtze River region under both scenarios. Semi-arid regions (Qinghai-Tibet Plateau) are more sensitive to climate change. The changes of SU and TXx are significantly smaller than FD and TNn under both SSPs scenarios. The obtained results will be of great significance for responding to international climate goals, formulating emission reduction policies, adopting adaptation measures and international cooperation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The harvesting efficiency achieved 99.2 % with the application of 60 g/L of FMT@DTAB. • PVDF integrated with extractants demonstrated enhanced butyric acid mass transfer. • Butyric acid showed improved mass transfer coefficient in PVDF with extractants. • PVDF-TDA achieved a 60 % recovery efficiency for butyric acid with 60 g/L of FMT@DTAB. Syngas fermentation utilizing acetogenic bacteria like Clostridium sp. provides a promising method for transforming CO and CO 2 -rich waste gases into valuable products such as short-chain fatty acids (SCFAs) and bio-alcohols, aiding in the reduction of greenhouse gas emissions and supporting carbon neutrality objectives. Magnetic nanoparticle-based coagulants, particularly Fe 3 O 4 @MIL-100(Fe)@TEOS@DTAB (FMT@DTAB), have recently attracted attention due to their efficient recovery and enhanced cell disruption capabilities enabled by cationic surfactant surface modifications. At a dosage of 60 g/L, FMT@DTAB has proven highly effective in achieving significant concentrations of acetic acid (7.06 g/L), butyric acid (6.27 g/L), ethanol (6.43 g/L), and butanol (5.24 g/L), along with notable harvesting efficiency (99.2 %) and intracellular ATP concentration (2.1 mM). Recent research on supported liquid membrane contactors highlights their cost-effective and environment-friendly properties, with an emphasis on minimal extractant usage. This study investigated the behavior of SCFAs using both virgin and supported liquid membrane contactors, focusing on factors such as organic extractant and membrane pore size. PVDF filled with tridodecylamine notably improved butyric acid recovery to around 60 %, with a mass flux of 14.95 ± 0.28 g/m2/h, outperforming virgin and other extractant-filled PVDF membranes. This study enhances resource efficiency and reduces industrial environmental impacts by optimizing the recovery and production of valuable chemicals from waste gases. It supports sustainable and economically viable biotechnology applications, aligning with global climate change mitigation efforts. [ABSTRACT FROM AUTHOR]

Since the Paris Agreement, European member countries have been committed to mitigating climate change and adapting to its effects. Climate action planning allows cities to organize their approach. It is critical to ensure that investments in infrastructure and services have a low-carbon impact and consider likely climate change perspectives. The output of this process is the climate action plan (CAP): one or more documents where a city sets out its roadmap to reduce greenhouse gas emissions and strengthen climate resilience throughout the community. Many cities have already developed and published a Paris Agreement-compatible CAP. The quality and compliance of these plans will also influence the achievement of the goals of the United Nations Framework Convention on Climate Change (UNFCCC, 2015). Thus, cities are crucial players in global climate change mitigation and adaptation efforts, and how they engage in climate policy is currently under debate. The paper is intended to support technological design, selecting good practices from the latest and most complete ones for climate mitigation and adaptation in urban settings. In particular, the paper focuses on public space and built environment regeneration actions that can tangibly contribute to the global climate resilience movement. Considering the operational difficulty that could arise in planning climate adaptation measures in historical urban contexts, the study critically analyzes current strategies in sedimented landscape realities of high cultural-historical value. The goal is to draw from them a cognitive and expeditious method of intervention that can be reiterated for similar contexts and is compatible with the consistency and value of urban and built heritage. The theme is timely and falls into Sustainable Development Goals No. 11 (sustainable cities and communities) and No. 13 (climate action). • The paper analyses the most recent studies and scientific papers on climate action plans. • Good practices for climate mitigation and adaptation in urban settings are critically investigated. • The study analyses current strategies in sedimented landscape realities of high historical and cultural value. • A toolkit is proposed that can be repurposed for similar contexts. [ABSTRACT FROM AUTHOR]

• First study to comprehensively address climate strategies for the O&G upstream sector in Brazil. • Decarbonization scenarios are simulated using a national Integrated Assessment Model (IAM). • O&G production can be sustained without compromising national decarbonization goals, but CO 2 and CH 4 emissions reductions must exceed simulated efforts to match industry leaders. • Ample potential to offset emissions through reforestation (∼ 500MtCO 2 /2050) and BECCS (∼ 400MtCO 2 /2050), presenting appealing business prospects for the industry. • CCS can play a vital role in advancing the decarbonization goals of both the sector and the country. Future projections of oil and gas demand suggest that some production will remain necessary. Although attention often focuses on CO 2 emissions from the combustion of their products, oil and gas production is also a relevant global emission source of both CO 2 and CH 4. Hence, understanding the carbon performance of upstream activities in producing nations is vital for distinguishing producers in a climate-pressured global market. This work explores climate strategies for the oil and gas upstream sector, using Brazil as a case study. The sector´s emissions profile is evaluated under distinct national climate scenarios. The analysis employs BLUES, a national Integrated Assessment Model (IAM), to access production volumes, mitigation measures applicable to the sector, and carbon dioxide removal potentials within the country to eventually offset the sector's remaining emissions. Results indicate sustained oil and gas production over the evaluated horizon (2020–2050) without compromising national climate goals, yet the sector's future emissions trajectory does not align with decarbonization targets pursued by more ambitious oil-producing nations and industry players. Despite sectoral mitigation measures indicated by the model, considerable emissions remain until 2050. Conversely, the country offers ample offsetting opportunities with potential synergies for the sector, especially through BECCS. Furthermore, the acceptability of offsets is discussed. [ABSTRACT FROM AUTHOR]

As the importance of non-state mitigation actions in the transition to a low-carbon economy becomes firmly established, a rapidly growing number of companies are setting corporate climate mitigation targets. Shareholders increasingly value these commitments, conveying the impression of good future carbon performance. However, a critical question emerges: why do some companies progress better than others toward their climate mitigation targets? There is currently a lack of empirical literature assessing companies' progress against their mitigation targets. Using a new indicator to evaluate the progress against individual corporate climate mitigation targets in a comparable manner, this study presents an explanatory analysis of 120 determinants applied to 4341 climate mitigation targets (scope 1 and 2 emissions) of 2975 companies reporting to the 2020 CDP questionnaire. The target progress assessment shows that 30% of targets have increased emissions since their base year, 15% have reduced their emissions but not at a sufficient pace, while 55% were on track to achieving or had already achieved their targets. In addition, 18% of targets were already achieved the year the target was set, which may be due to choosing a base year with unusually high emissions. The findings reveal 19 key determinants significantly associated with the progress against corporate targets and highlight future research orientation. Our results indicate better progression by companies having absolute targets with longer timeframes and disclosing additional, as well as remuneration links to climate-related issues. Companies with more ambitious targets progress less than others, except when the ambitious targets are approved by the Science-Based Targets initiative. The latter implies ambitious targets from some firms may only be symbolic, and that investors should consider both target ambition and progress. Clear guidance and regulations should be implemented by policymakers to prevent misleading target information. Future research should address limitations related to reliance on self-reported data and exclusion of scope 3 emissions targets, along with the research directions suggested by the findings. [ABSTRACT FROM AUTHOR]

• Climate policy should be diversified to meet the needs of all countries. • The ability of renewable energy to solve the emissions problem is questioned. • The energy efficiency has no statistically significant changes in 2010–2020. • There is a contradiction between Sustainable Development Goals 7 and 13. Improving energy efficiency is considered to be important and cost-effective strategies to reduce greenhouse gas emissions, which is crucial in the face of global climate change. This study hypothesizes that there are significant differences in the impact of energy efficiency on economic and energy systems. Using quantile regression method, the impact of economic and energy characteristics on energy-related greenhouse gas emissions in 120 countries over the period 2010–2020 is investigated. Detailed analyses are conducted by dividing the countries into 12 groups based on gross national income per capita (Atlas method) and the share of resource rents in gross domestic product. A macro-level system of indicators for assessing energy efficiency is proposed, which can be linked to the economic and energy characteristics of the systems: National Energy Efficiency, Energy Intensity Ratio, Primary Energy Production Efficiency, Industrial Sector Energy Efficiency, Share of Low Carbon Energy, Population Energy Efficiency. The findings show that (1) global energy efficiency has remained largely unchanged over the decade; (2) there are differences in energy efficiency between fossil fuel producing and non-fossil fuel producing countries; (3) the factors that have an inverse effect on emissions in fossil fuels dependent countries include industrial energy efficiency and population energy efficiency, which are far from exhausting their potential; (4) despite the recognized importance of energy efficiency, its impact on reducing greenhouse gas emissions globally has been unnoticeable. The study highlights that Sustainable Development Goals 7 and 13 on energy affordability and emission reductions are conflicting and require harmonization of mechanisms to achieve them, such as balancing climate change mitigation investments, identifying the potential for energy efficiency improvements across economy or improving energy saving practices. The overall conclusion suggests that there is an urgent need to review current decarbonization and energy efficiency initiatives, given the lack of significant global progress in reducing greenhouse gas emissions or improving energy efficiency between 2010 and 2020. [ABSTRACT FROM AUTHOR]

• Insights from transportation research used to improve comprehensive ESOM. • Capturing underlying heterogeneities by increasing contextual model resolution. • The setup underpins importance of tailoring climate strategies to specific settings. • Behavioural shifts have different implications depending on the contextual setting. • Failing to address key cost barriers delays car fleet electrification by five years. Meeting ambitious climate targets requires deep cuts in emissions from passenger transportation. Many studies point to electrification and behavioural shifts as key measures. Spatial, demographic, economic, and transport-sector-related factors shape the opportunities and preferences for change, thus setting the direction and pace of the transition. These factors typically differ between urban, suburban and low-population-density settings, a fact that is generally overlooked in comprehensive energy system optimisation models (ESOM). This study introduces a novel contextual representation of passenger transportation within a national ESOM (TIMES-Sweden). When testing the new approach, different cost barriers to electrification are found across various settings, signalling a need for different policy responses. Further, opportunities for – and impact from – shifts in travel behaviours vary significantly across settings. These results highlight the need for climate change mitigation strategies in passenger transportation which are better tailored to specific contexts. [ABSTRACT FROM AUTHOR]

Carbon neutrality strategies have a significant role in climate mitigation efforts. As global concerns regarding climate change continue to increase, achieving carbon neutrality has emerged as a paramount objective for reducing greenhouse gas emissions and limiting the adverse impacts of anthropogenic activities on the environment. This research investigates a wide range of scholarly works to conduct an in-depth analysis and synthesis of the relevant information about carbon neutrality strategies. The review introduces carbon neutrality principles and terminologies, highlighting their importance in climate mitigation. It then proceeds to explore the wide range of strategies employed across different sectors and industries, investigating their effectiveness, scalability, and potential challenges. A multidimensional analysis contrasts the United States Nationally Determined Contributions pathway 2023, China's Nationally Determined contributions 2023, and the EU Directive 2023/2413, assessing their economic, environmental, political, and social impacts. The study evaluates strategies' effectiveness, scalability, and innovation for transitioning to a sustainable, low-carbon future. It fills a gap by analyzing global approaches across the US, China, and the EU, which account for about 50% of the world's total GHG emissions. It evaluates the novel application of diverse strategies, from renewable energy transitions to innovative policy measures, highlighting their potential to mitigate climate change effectively. By providing a multidimensional analysis of these strategies' impacts, the research not only enhances understanding of effective carbon neutrality tactics but also underscores the importance of international cooperation in realizing a sustainable, low-carbon future. • Identifies and analyzes carbon neutrality strategies, emphasizing the need for diverse US, Chinese, and EU approaches. • Evaluate renewable energy, carbon capture, and policy tools for carbon reduction effectiveness, scalability, and innovation. • Highlights the study's novelty in synthesizing current knowledge on carbon neutrality, addressing a significant research gap. • Concludes with strategic ideas for international collaboration and policy development for low-carbon futures. [ABSTRACT FROM AUTHOR]

China has made substantial investment in agricultural research and development (R&D) to promote technological change (TC). Although the role of TC in enhancing agricultural production and mitigating environmental impacts is widely recognized in separate contexts, knowledge about its' effects on food security and the environment, especially with a focus on China, is still lacking. This study uses an agro-economic optimization model to assess the impact of TC on food security and climate change mitigation. Our results indicate that TC plays an important role in improving agricultural productivity, which, in turn, contributes to a comparative advantage in agricultural trade. It also strengthens food security through lowering food prices. By contrast, a higher TC level increases greenhouse gas (GHG) emissions, albeit marginally, due to higher agricultural production for exports. This indicates a rebound effect of agricultural productivity on GHG emissions. Therefore, additional efforts are required in China to improve food security without compromising GHG mitigation. • Technological change (TC) enhances China's agricultural production and comparative advantage in trade. • A higher level of TC within China's agriculture and land-use (AFOLU) sectors could contribute to lowering food prices in China. • Increase in TC within China's AFOLU sectors can causes trade-offs between food security and climate change mitigation. [ABSTRACT FROM AUTHOR]

• Analyses CCS technological innovation system dynamics in Norway. • Employs the technological innovation system (TIS) framework. • Overall the CCS innovation system has intermediate-weak performance. • Momentum is however positive, albeit future prospects being uncertain. CO 2 Capture and Storage (CCS) is today seen as a key technology to cut carbon emissions in many hard-to-abate sectors such as energy-intensive processing industries and the waste sector. Although CO 2 capture is technically possible, key challenges for realizing CCS persist. Over the past decade, CCS has taken a new direction with more focus on application in energy-intensive industries rather than the energy sector. For CCS value chains to materialize, innovation and implementation thus needs to occur amongst an array of actors, with different innovation modes, institutions, and policy regimes, and with varying sectoral capacities for adaptation and change. There has so far been limited social science research on CCS innovation dynamics, which we suggest approaching as a socio-technical change process. To better understand this process, we draw on the sustainability transitions research field and employ the Technological Innovation System (TIS) framework to study the CCS innovation system in Norway. We find that, overall, the Norwegian CCS TIS displays systemic weaknesses for example in the form of market formation and resource mobilization, yet recent developments suggest a relatively positive momentum for this technological field which is key to meeting Norwegian and global climate mitigation targets. [ABSTRACT FROM AUTHOR]

Global climate action is the grand challenge of the 21st century. Large reductions in greenhouse gas emissions are needed, with net-zero CO 2 emissions by mid-century a requirement for many scenarios that restrain global warming below 1.5 °C by 2100. This will require massive deployment of renewables such as ground-based solar and wind, increased long-distance grid transmission capacity, and electrification of much of the global economy. Increased electrification, coupled with rising standards of living in developing countries, will drive ever-larger electricity demand to 2050 and beyond. And the intermittency, land-use, and transmission requirements of ground-based solar and wind present challenges to large-scale deployment to meet Net Zero targets. Space-based solar power (SSP) presents an enticing alternative, and with full reusability of upcoming heavy launch vehicles and modular SSP architectures, the economics of deployment are expected to become favorable in the coming decades. Efforts exist today to deploy demonstrators this decade, with initial production systems by 2050. However, deploying SSP at the scale required to address rising, global electricity demand will itself require orders-of-magnitude greater launch frequencies. If heavy launch frequency does not increase quickly enough, due to environmental concerns, launch site competition, or other bottlenecks, the dropping cost of launch will not be sufficient to enable SSP for global impact this century. A space elevator (SE) development program like that proposed by the International Space Elevator Consortium (ISEC) offers an alternative delivery mechanism for scaling SSP beyond 2050, hedging the risk of reliance on a single delivery system while reducing the time required for large-scale SSP deployment. To de-risk possible futures in which SSP is a major part of the global energy mix this century, a dual space access architecture is proposed, leveraging the strengths of heavy launch and SEs together. Such an architecture would secure the future for green energy on Earth, in 2050 and beyond. • Net-zero CO 2 emissions by 2050 required for many climate scenarios with < 1. 5 °C warming. • Massive deployment of renewables and scale-ups of long-distance transmission required. • Space-based solar power (SSP) is becoming economically viable as an enticing alternative. • Reusable heavy launch must scale-up rapidly to deploy SSP at scale for net-zero. • A space elevator development program would de-risk delivery of SSP at scale. [ABSTRACT FROM AUTHOR]

Cocoa production is a leading driver of deforestation in the humid-tropics of West Africa. Reconciling climate change mitigation with livelihoods of farmers requires identification of production strategies to concurrently improve yield and profit while curtailing emissions of greenhouse gases (GHG). Using a 2021 plot-survey conducted in Ghana's Eastern region, we evaluated yields, GHG emissions, and value of production (VOP) (a profit indicator) across a typology representing the diversity of systems at plot-level. The typology was constructed by first stratifying plots according to shade levels and variety (hybrid vs. Amazonia) which resulted in three systems: Hybrid sun , hybrid variety under full-sun (little to no shade); Hybrid shade , hybrid and moderate shade (13–25 shade trees ha−1); and Amazonia, Amazonia under predominantly moderate shade. Next, factor analysis and clustering were used to group plots within each system according to cocoa yield, vegetation, management, and (local) climate conditions. Cluster analysis showed that fertiliser, weeding, pruning, hand pollination, cocoa tree density, and shade tree densities of differing heights were most influential for determination across systems. Hybrid shade had the highest net GHG removal rate at −6.8 ± 1.7 (± 95% CI) Mg CO 2 eq ha−1 yr−1: 48% and 127% higher (emissions more negative) respectively over Amazonia and Hybrid sun. Hybrid shade additionally had the highest average and least variable VOP among production systems at 669 ± 564 USD ha−1 yr−1, compared to Hybrid sun and Amazonia at 404 ± 442 and 213 ± 280 USD ha−1 yr−1 respectively. These results point to hybrid cocoa grown under moderate shade of 13–25 shade trees ha−1 as optimal for reconciling climate change mitigation with development in West African cocoa. • Study concurrently evaluates financial profits and GHG balances (N 2 O & CH 4 emissions, CO 2 removals) in West African cocoa. • Plot-level indicators are evaluated across a typology obtained from sample-stratification and clustering. • Hybrid cocoa under moderate shade (13-25 shade trees ha-1) had GHG removal increment of 127% over same variety without shade. • This system too had higher mean profits, thus best reconciling GHG mitigation and economic development for the region. [ABSTRACT FROM AUTHOR]

Achieving decarbonisation of the heating sector is a major challenge, especially in Ireland, which has the lowest proportion of renewable heat in Europe. In economically pursuing ambitious and equitable climate targets, Ireland's Climate Action Plan 2023 set a goal of reaching 2.5 TWh of district heating by 2030, starting from a limited existing capacity. This pioneering study explores supply sources and heat density demand cohorts to develop a model to understand district heating in a low-deployment region, using Ireland as a case study. We also conduct a sensitivity analysis considering different connection rates. Our research demonstrates that district heating is pivotal in achieving optimal decarbonisation pathways. Incorporating district heating reduces marginal CO 2 emission prices by 13%–25%. Additionally, with feasible growth limits applied, total savings for the energy system are anticipated to reach €17.2 billion by 2050. This reduction of emissions in the building sector, facilitated by district heating, allows for greater emissions allowances in other sectors and reduces reliance on electricity while meeting climate targets. These insights highlight the need for spatial energy policies and deepen our understanding of integrating district heating within an energy system optimisation model. • District heating in Ireland can reduce marginal CO 2 emission prices by 13%–25%. • District heating can cumulatively save €17.2 billion compared to no district heating. • Regional energy policy is needed to align with cost-optimal pathways. • Regional supply and demand quantified sensitivity analysis strengthens insights. [ABSTRACT FROM AUTHOR]

Efforts to enhance greenhouse gas (GHG) emission reduction in East Asia play a pivotal role on both global and regional scales in advancing climate mitigation strategies. This study aimed to better constrain anthropogenic CO 2 emission estimates by expanding the network of near-surface in-situ stations for CO 2 observations across South Korea. To achieve an optimal CO 2 network design, we conducted an Observing System Simulation Experiment (OSSE) coupled with the Stochastic Lagrangian Transport model (STILT), utilizing meteorological data from the Korean Integrated Model (KIM). Our inversion setup incorporated two CO 2 emission datasets with a 0.1o resolution: EDGAR v6 for prior emissions and GRACED for truth emissions. A uniform model-mismatch error of 3 ppm was introduced across sites. The effectiveness of the existing five in-situ stations, termed the base network, in South Korea was evaluated to gauge their ability to constrain CO 2 surface flux estimates. However, the findings revealed a reduction in flux uncertainty of only 29.2%, which fell short of the desired uncertainty reduction goal. In this base network, the Lotte World Tower (LWT: 37.5126°E, 127.1025°E) in Seoul and the Anmyeondo (AMY: 36.538576° N, 126.330071° E) site in Taean county stood as major contributors, with estimated reductions of 17.48% and 6.35%, respectively. Consequently, we proposed and developed an extended network, identifying seven candidate sites based on consideration of logistical factors, existing infrastructures, and proximity to the emission source regions. An incremental optimization scheme ranked their contributions, resulting in an additional 25% reduction, bringing the total to 54.13%. However, it is noteworthy that diminishing returns (ranging from 13% to less than 0.1%) were observed with an increase in station count mainly due to the possibility that adding a station earlier in the sequence might render subsequent stations redundant. Despite this, the proposed CO 2 network successfully reduced uncertainty in emissions, narrowing the gap with the objectives of the Global Greenhouse Gas Watch (G3W). • Designing CO 2 near-surface observation network over South Korea. • New stations selected considering logistic factors, existing infrastructures, and proximity to emission sources. • The base network was able to reduce 29.18% of the uncertainty in CO 2 emissions. • Extending network, by adding new seven candidate sites, led to a total uncertainty reduction of 54.13%. [ABSTRACT FROM AUTHOR]

• Attractive names can increase the appeal of plant-based meals. • Appeal scores for plant-based meals are associated with plant-based choices. • Appealing names might increase plant-based choices among flexible meat eaters. Reducing meat consumption could materially reduce global greenhouse gas emissions. Yet, meat consumption habits are exceptionally difficult to break, even more so when plant-based meals are described using unappealing names. Past interventions that attempted to alter consumer choice by changing meal names at restaurants reported only modest effects. We propose that interventions aimed at increasing demand for plant-based meals may be more effective if: (1) meal naming is informed by theory; (2) the affective appeal of meal names is tested before deployment; (3) meat-based meal names are deliberately kept basic; and (4) heterogeneity of different meat-eater segments is accounted for. We conduct three studies. Study 1 evaluates the appeal of several alternative theory-informed names of plant-based meals, highlighting taste, provenience, and/or texture. Study 2 assesses the effectiveness of appealing names on stated plant-based choices across the general Australian population, and Study 3 for market segments of meat-eaters. Results indicate that highlighting flavour, provenience, and texture can impact the appeal of plant-based meals. Increased appeal does not translate to increased plant-based meal choices across all consumers but does have a potential impact for a specific group of more flexible meat-eaters. We conclude that using appealing names for plant-based dishes on restaurant menus may represent a cost-effective way to entice specific market segments of consumers to choose plant-based rather than meat-based dishes when dining. With food contributing nearly 25% to global emissions, changing meal choices for even the smallest of market segments can make a meaningful contribution to climate change mitigation. [ABSTRACT FROM AUTHOR]

Superblocks are traffic-calmed neighborhoods that contribute to climate change mitigation and improve living and health conditions of inhabitants without requiring extensive reconstructions. This article investigates experiments with superblocks in Vienna (Austria) from initial discussion to the first experimental implementation. We use an integrated mixed-method approach: First, we examined potential climate and health benefits of three hypothetical superblock sites through transport modeling. We then conducted stakeholder interviews at two points of time to investigate the perceived acceptance of superblocks and to examine how superblock experiments align with the conventional planning regime, thereby focusing on actor's composition, dominant discourses, and mode of governance. The modeling results suggest that reductions in greenhouse gas emissions and public health benefits are 2–3 times higher when superblocks are implemented in more deprived compared to more affluent urban areas. In the course of implementing the first superblock experiment in Vienna, the discursive reframing of superblocks as a redistributive intervention, which we could trace through the interviews, resulted in implementing the pilot project in a district with the most beneficial sustainability outcomes. • From discussion to implementation: investigating Vienna's superblock experiments. • To derive potential climate and health benefits we applied transport modeling. • To derive drives of superblock implementation we conducted interviews. • Potential climate and health outcomes are the highest in more deprived urban area. • Superblocks became re-framed as a redistribution intervention. [ABSTRACT FROM AUTHOR]

Using the recently proposed concept of "design coalitions," this paper analyzes stakeholder participation in a subnational U.S. climate change mitigation policy redesign process. We demonstrate the utility of design coalitions for analyzing policy design processes, contending that it provides an opportunity to examine the understudied "secondary beliefs" of actors as described by the advocacy coalition framework. Our case study consists of an iterative, inductive content analysis of written input to the Regional Greenhouse Gas Initiative's 2016 policy redesign process. We developed a typology of 12 distinct stakeholder types who coalesced in 19 separate design coalitions, each espousing a stance on one of 11 elements of the policy design. These coalitions were dynamic, with radically different sets of stakeholder types participating simultaneously in many different design coalitions without coordination, usually for their own unique reasons. We observe that, although the updated policy reflected many stakeholder's stances, their influence was limited by their exclusion from the agenda-setting phase of this policy redesign process. In this critical era of climate mitigation policy proliferation, it is important to develop a better understanding of climate policy design coalitions and how they engage in and influence climate mitigation policy design processes. • This research expands knowledge of actor engagement in climate policy design processes. • We develop the concept of design coalitions & explore its relevance to climate policy. • Here, actors aligned in design coalitions based on the "secondary beliefs" of the ACF. • Each type of stakeholder participated in a unique set of design coalitions. [ABSTRACT FROM AUTHOR]

Sub-Saharan Africa is a region with a large population living without electricity. This study investigates the grid balancing role of bioenergy in a sub-Saharan Africa's fully renewable power sector to address the energy poverty challenge in the region, using Ghana as a case country. Two methods are employed: the bioenergy estimation method, for deriving Ghana's technical bioenergy potential, and the LUT model, for the power sector transition modelling. The Ghanaian bioenergy potential of 48.3 TWh is applied on the power sector using the LUT model to develop six alternative scenarios, emphasising on the role of bioenergy, greenhouse gas emissions costs, and climate change mitigation policies. The results of the Best Policy Scenario reveal that with an electrical efficiency of 37.2%, 18 TWh of electricity, which is 16.9% of Ghana's electricity demand by 2050, could be produced from bioenergy for grid balancing. Also, the levelised cost of electricity declines from 48.7 €/MW in 2015 to 36.9–46.6 €/MWh in 2050. Whereas the cost of electricity increases to 76.4 €/MWh in the Current Policy Scenario without greenhouse gas emissions costs. The results show the viability of a relatively cheap and bioenergy balanced sustainable renewable power system for the sub-Saharan African region. • The role of modern bioenergy is examined in renewable energy (RE) dominated power systems. • A comprehensive bioenergy potential assessment for the case of Ghana is presented. • Bioenergy provides flexibility in hybrid solar PV-battery dominated power systems. • Levelised cost of electricity for 100% RE ranges from 37 - 46.6 €/MWh in 2050. • Sustainable modern bioenergy contribution in power systems substantially reduces system costs. [ABSTRACT FROM AUTHOR]

The Chinese government has announced ambitious carbon reduction goals to address climate change, however, there has been limited scientific attention to the achievement of deep decarbonization in regions with insufficient economic development. Moreover, the complex impacts of climate change mitigation on energy system, environment and economic development remain unclear in Northwest China. Here we construct a comprehensive evaluation model system to evaluate the effects of different climate mitigation pathways in Qinghai, Ningxia, Gansu and Xinjiang provinces. Results show that the four provinces need to vigorously increase the share of electricity that consumed in final energy to 53.1–60.0% and 52.9–62.0% for 2 °C and 1.5 °C target, respectively, and reduce total energy demand to 11.6–44.4 Mtoe and 8.2–34.1 Mtoe in 2050. Meanwhile, the CO 2 emissions for their energy systems will reach peak by 2025 at lower values. Moreover, the synergies of CO 2 reduction are most conducive to abating SO 2 pollution and also contributing to decreasing PM 2.5 concentrations. Additionally, the GDP losses in 2050 fluctuate from 5.0 to 21.7 billion USD in the 2 °C scenario to 11.5–52.7 billion USD in the 1.5 °C scenario. Our study provides practical guidance on achieving carbon reductions in less developed regions of China and lays foundations to promote decarbonization of energy systems in other provinces. • Realizing climate goals requires low-carbon energy systems led by electricity. • Energy-related carbon emissions in Northwest China will peak by 2025. • More ambitious climate and clean air policies are needed for air quality improvement. • Economic loss shows an upward trend in the future under climate targets. [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]

This study investigates the impact of alternative fertilization practices on the yield-scaled global warming potential (YS-GWP) in almond orchards. Almond production is a contributor to greenhouse gas emissions, primarily due to nitrogen-based mineral fertilizers. This research aims to identify strategies that reduce the environmental footprint of almond cultivation while maintaining yield. Field experiments were conducted in an almond orchard using three alternative fertigation practices: Advance Grower Practice (AGP), Pump and Fertilize (P&F), and High Frequency Low Concentration (HFLC). AGP is the current practice used by producers to meet annual N demand for almond tree growth; P&F is a reduction in applied N rate in response to measured N concentrations in the groundwater so that the added N and groundwater N reach the same total N applied; HFLC is a practice of applying smaller N rates per individual event. HFLC uses a greater number of fertigation events to reach similar total annual N load as other treatments. Cumulative N 2 O and CH 4 emissions were used to determine GWP by converting the emissions to carbon dioxide equivalents (CO 2 eq) within a 100-year horizon. Nitrous oxide emissions were multiplied by a radiative forcing potential CO 2 eq of 298 and CH 4 by 25 (UNFCCC, 2007). The results revealed that both P&F and HFLC reduced the YS-GWP compared to AGP. HFLC demonstrated 52–78% decrease in GWP per unit of almond yield compared to AGP, while P&F showed 48–58% decrease over AGP. These reductions were attributed to the reduced nitrous oxide emissions associated with P&F and HFLC. Further, P&F and HFLC tended to have higher N use efficiency than AGP. We demonstrate that adopting alternative fertilization practices can effectively mitigate the environmental footprint of almond orchards while maintaining crop yields. These practices offer viable options for almond growers to reduce greenhouse gas emissions, enhance sustainability, and contribute to climate change mitigation. • Applying nitrogen fertilizer at a lower amount and higher frequency reduces nitrous oxide emissions. • This practice tends to have higher nitrogen use efficiency than standard practice. • It maintains commercial yields at the same level as the standard practice. • It lowers Yield Scaled Global Warming Potential more than the standard practice. [ABSTRACT FROM AUTHOR]

Carbon dioxide removal (CDR) is recognized as an important tool for addressing residual emissions and achieving net-zero emission targets. While some have cautioned that a focus on CDR in policy processes may lead to delayed efforts to mitigate emissions, others have argued that such concerns are unwarranted. Nevertheless, the circumstances under which CDR could help or delay emissions mitigation in given contexts remain unclear. This paper explores the emerging discourse on CDR in Switzerland. We examined how the CDR community legitimizes CDR and limits its scope, and what the implications are for emissions mitigation. Switzerland is home to growing businesses in CDR and has pioneered the implementation of international offsetting projects under Article 6.2 of the Paris Agreement. We found that numerous promises help legitimize and attract interest in CDR. Actors use discursive strategies and rules to limit CDR and avoid disappointment in its contribution to climate mitigation. The idea that emission reduction should prevail over removal is promoted accordingly, which ironically helps legitimize the CDR idea yet dodges the question of how much removal is possible and for balancing which emissions. Superficial engagement with the issue is reinforced by the normalization of inflated promises and the sentiment that the mitigation deterrence rhetoric erodes trust in CDR. We argue that this can contribute to mitigation delays by evading the debate on what it is possible to remove and taking resources from alternative measures. We recommend a thorough discussion to examine the risks and the implementation of rules that minimize them. • Mitigation deterrence discourse leads to efforts to avoid substitution dynamics. • "Reductions first" legitimizes CDR without coordinating emission residuals. • Inflated promises of CDR may reduce resources for more realistic measures. • Attention to CDR dynamics is required to help achieve comprehensive decarbonization. [ABSTRACT FROM AUTHOR]

Southeast Asia (SEA) is a key producer and exporter of rice, accounting for around 28% of rice produced globally. To effectively mitigate greenhouse gas (GHG) emissions in SEA rice systems, field methane (CH 4) and nitrous oxide (N 2 O) emissions have been intensively studied. However, an integrated assessment of system-level GHG emissions which includes other carbon (C) balance components, such as soil organic carbon (SOC) or energy use, that can positively or negatively influence the net capacity for climate change mitigation is lacking. We conducted a systematic review of published research in SEA rice systems to synthesize findings across four main components of net system emissions: (1) field GHG emissions, (2) energy inputs, (3) residue utilization beyond the field, and (4) SOC change. The objectives were to highlight effective mitigation opportunities and explore cross-component effects to identify tradeoffs and key knowledge gaps. Field GHG emissions were the largest contributor to net system emissions in agreement with existing scientific consensus, with results showing that practices such as floodwater drainage and residue removal are sound options for CH 4 mitigation. On the other hand, increasing SOC potentially provides a large GHG mitigation opportunity, with long-term continuous rice cropping and practices such as residue incorporation and biochar application promoting SOC increase. A reduction in energy inputs was mainly achieved by optimizing agrochemical use, especially N fertilizers. For residue utilization beyond the field, GHG emission mitigation mainly came from preventing open field burning through residue removal. Removed residue can subsequently be used for producing energy that offsets GHG emissions associated with conventional fuel sources (e.g. fossil fuel-based electricity generation) or substituting material used in other production systems. Integrating all four components of net system emissions into one analysis underscores the following two main takeaways. First, the components of field GHG emissions and SOC change are the biggest opportunities for reducing net system emissions and need to be considered for effective climate change mitigation. Second, the reduction of C inputs through residue removal and increased soil aeration through multiple drainage will lower CH 4 emissions but may also potentially decrease SOC stocks over time. Hence, we argue that future research needs to consider cross-component effects to optimize net system emissions, specifically the "stacking" of best management practices for mitigation related to field GHG emissions or SOC change in long-term experiments. • Net system emissions include field CH 4 /N 2 O emissions, energy inputs, residue utilization, and SOC change. • Integrated review highlights cross-component effects of management including tradeoffs. • Field GHG emissions and SOC change are the largest opportunities for mitigation. • Reduced C inputs and drainage decrease CH 4 emissions, but may negatively affect SOC. • "Stacking" of best management practices is a key knowledge gap that warrants research. [ABSTRACT FROM AUTHOR]

Much recent research on climate change mitigation has focused on carbon intensities, i.e. emissions per unit of economic value, to better understand interrelationships of decarbonization with value. This paper studies large tourism enterprises, which account for a large share of tourism's emissions. Based on annual reports, the paper evaluates greenhouse gas emission and revenue interrelationships for a total of n = 29 large tourism companies including airlines, cruise lines and accommodation businesses. Together, these companies represent about 13% (365 Mt CO 2) of global tourism emissions, generating revenues of US$477 billion (in 2019). The paper tracks their total emissions and emission intensities over the period 2015–2019, revealing that large tourism firms are not on track to net-zero. Results show considerable differences in emission intensities between the three tourism subsectors and between individual firms within the subsectors. These findings are discussed against emission reduction needs to mid-century. There is strong evidence that continued growth at industry's expected rates represents an insurmountable barrier to net-zero, contradicting industry narratives of progressively and successfully engaging with climate change mitigation. [ABSTRACT FROM AUTHOR]

Identifying transmission sectors that may not be revealed by existing indicators, such as production-based emission (PBE) and consumption-based emission (CBE) accounting, is significant in emission reduction policies and provides insights into novel opportunities for companies and industries to reduce emissions. This study proposed an intermediate-based emission (IBE) accounting approach that considers indirect emissions from intermediate goods production and a case study was conducted using Exiobase 3.8. The highest IBE sector was 'basic iron' (1131 Mt-CO 2), and the sector's IBE was higher than its PBE (1052 Mt-CO 2). Additionally, the material sector, such as aluminum products (326 Mt-CO 2), was identified as a key transmission sector, although PBE (21 Mt-CO 2) and CBE (3 Mt-CO 2) of the sector is very low. In addition, IBEs were observed to be closely related to overall supply chain emissions in Germany, Japan, and Asia, and cooperation is required to reduce the emissions. The method enables approaching supply chains with large emissions from three perspectives (production-, consumption-, and intermediate-based accounting) and exploration of the emission reduction responsibilities of the three key sectors. The utility and discussion of the approach are consistent with Scope 3 emissions and facilitate fair allocation of emission reduction responsibilities to a larger number of countries and industries. • This study suggested intermediate-based emission (IBE) accounting. • Industries such as basic iron have high production–based emissions but higher IBE. • Intermediate industries not focused on by existing emission accounting identified. • Existing betweenness-based emission accounting much higher than actual emissions. • Germany, Japan, and Asian HEMs have strong correlation with IBE. [ABSTRACT FROM AUTHOR]

Malaysia is actively addressing environmental responsibilities by pledging a 45 % reduction in greenhouse gas emissions by 2030, aided by a large-scale solar photovoltaic initiative. Nonetheless, the unprecedented meteorological events due to climate change such as extreme temperatures and precipitation may reduce the large-scale solar performance and lead to infrastructure damage. The primary objective of this study is to conduct a screening-level analysis from both technical and economic perspectives, in order to assess the effects of extreme temperature and precipitation on large scale solar in Malaysia. This study hypothesized that extreme temperature and precipitation reduce large scale solar performance and increase infrastructure damage. The results demonstrate that both extreme temperature and precipitation increase the power and efficiency loss over time. In general, infrastructure damages caused by extreme temperature and precipitation can result in degradation, a shortened lifespan, and ultimately a collapse. In this study, the costs of physical damage were estimated using the modified levelized cost of energy, and it was found that the cost of physical damage in extreme temperature conditions was approximately 30 % greater than the cost in extreme precipitation conditions, which was nine times greater than in normal condition. Compared to a no-adaptation scenario, it is possible to reduce the additional costs due to extreme temperature and precipitation by up to 53 % and 49 %, respectively. Enhancements, additional analysis, and validation of these findings could aid in the readiness for climate change mitigation efforts, not only for solar power systems but also for other types of energy systems. [Display omitted] • Generic screening-level analysis for assessing techno-economic impact of solar. • Extreme temperature and precipitation reduce solar performance and increase damage. • Study employs modified levelized cost of energy to estimate physical damage costs. • A proactive adaptation strategy reduced the additional cost for both scenarios. [ABSTRACT FROM AUTHOR]

Carbon emission reduction in China matters to global climate change mitigation. China has been experiencing extensive land changes, which profoundly influence terrestrial ecosystem carbon storage (TECS) and carbon emissions. Scholars have predicted influences of land changes on TECS in China with scenarios obtained from global integrated assessment models (IAMs), which lack national details. Moreover, universally existing variations in land-use intensity have not been considered when estimating influences on TECS. This study simulated changes of land-use intensity of China from 2000 to 2050 using CLUMondo under China-specified policies for sustainable development modeled by a national IAM named Threshold21-China. We proposed a more precise TECS estimation method by distinguishing land-vegetation and land-soil types. Results demonstrated that under scenario with preceding policies, the total TECS can increase by 865.5 Tg C from 2000 to 2050. Through implementing preceding policies, TECS loss by conversions from cultivated land to artificial surfaces can decline by 82 Tg C, and new TECS accumulated by increased and densified forests can increase by 73 Tg C. Mountainous and rapidly urbanizing regions are sensitively influenced and need more restrict land change management policies. This study demonstrates the significance of sustainable development policies for TECS conservation and indicates specific critical regions. • Introducing national IAM into land change simulation. • Considering land-use intensities in land change simulation. • Proposing an improved TECS estimation method. • Estimating influences of land changes on China's TECS. • TECS accumulation could be improved under sustainable policies. [ABSTRACT FROM AUTHOR]

Communication strategies designed to strengthen individual and community climate action play a key role in reducing greenhouse gas emissions and averting worst-case climate scenarios. However, communicating climate change in a way that motivates action remains a significant challenge. Through two experimental surveys with representative samples of Australian residents (n 1 =723, n 2 =729), we investigated whether climate messages that highlight relevant and iconic places, such as the Great Barrier Reef (GBR), could strengthen individual action on climate change and if so, what messages are most effective in motivating climate-related behaviour. Participants were randomly allocated to receive one of eight messages about climate change and/or the GBR, or a control condition. In Study 1, we found that climate messages centred around the GBR are more effective in strengthening intentions to adopt energy reduction behaviours than generic (non-reef) climate messages when compared to control. However, we find that they are limited in their ability to motivate more impactful civic and social behaviours, including those which seek to influence climate policy support. In Study 2, we found that messages emphasising collective efficacy can enhance message effect and influence the uptake of a broader range of behaviours, both intentions and in situ behaviour. Mediation analysis suggests that this effect was largely driven by emotions related to distress and that place identity and positive emotions did not play a significant role. This research offers an alternative for those looking to expand beyond traditional climate communication strategies and has implications for both theory and practice. [Display omitted] • Centring climate messages around iconic places may promote action. • We conduct two messaging experiments using the Great Barrier Reef as an example. • Reef messages can strengthen behavioural intentions compared to generic messages. • Collective efficacy statements and public-sphere calls to action enhance the effect. • Message effect is largely driven by emotional responses related to distress. [ABSTRACT FROM AUTHOR]

• The SLIM scenarios improve lifestyle change representation in model-based scenarios. • Developing quantitative lifestyle scenarios requires detailed narratives. • Equity representation in scenario modelling improves with regional differentiation. • Lifestyle changes in systems change notably contribute to climate change mitigation. • The SLIM scenarios inform policymakers about facilitating impactful lifestyle change. Sustainable lifestyles and behaviour changes can be vital in climate change mitigation. Various disciplines analyse the potential for such changes – but without much interaction. Qualitative studies look into the change process (e.g. social practice theory), while quantitative studies often focus on their impact in stylised cases (e.g. energy modelling). A more holistic approach can provide insightful scenarios with diverse lifestyle changes based on informed narratives for quantifying long-term impacts. This research explores how comprehensive sustainable lifestyle scenarios, coined SLIM (Sustainable Living in Models) scenarios, could contribute to transport and residential emission reductions. By translating and quantifying lifestyle scenario narratives through engagements with advisors and policymakers, we modelled two distinct lifestyle scenarios which differ in their degree of access to structural support. In one scenario, governments, corporations and cities leverage existing values and market systems to shape citizen and consumer preferences and everyday practices. In the other scenario, people adopt ambitious sustainable lifestyle behaviours and practices through peer-to-peer interaction and digital technology. We quantified the scenarios based on motivations, contextual factors, extent, and speed of lifestyle adoptions with regional differentiation. Furthermore, we applied heterogenous adopter groups to determine the model inputs. We present the resulting pathways in per capita emissions and more detailed changes in total emissions via decomposition analyses. We conclude that regional differentiation of the scenario narratives and modelling of intra-regional differences allows accounting for equity in lifestyle changes to a certain extent. Furthermore, new technologies are more important for enabling lifestyle change in a scenario with than a scenario without strong structural support. With strong structural support, lifestyle changes reduce transport and residential emissions to a larger degree (about 39% for Global North and 27% for Global South overall in 2050 relative to a "Middle-of-the-Road" SSP2 reference scenario in 2050). Thus, lifestyle changes in larger systems change are essential for effective climate change mitigation. [ABSTRACT FROM AUTHOR]

• Attitudes towards GHG mitigation and climate change adaptation are assessed. • Study subjects include sheep farmers, extension officers and scientists involved in sheep farming research. • Extension officers and sheep farmers show converging negative attitudes towards mitigation. • Beliefs and information are found to cause diverging attitudes. • Consequences on the working of the knowledge transfer chain and implications for policy design are discussed. Low innovation adoption rates in agriculture have spurred intense research on farmers' attitudes and motivations. Little attention has been paid to attitudes of other important actors in the knowledge transfer chain. Evidence indeed suggests that adoption rarely happens at the farm level, but requires the right inputs from science and extension services. Divergent attitudes among actors in the knowledge transfer chain may hence contribute to low adoption rates by transferring insufficient, outdated, irrelevant and/or incorrect information. This study is an investigation on attitudes towards climate change mitigation and adaptation of three classes of actors: sheep farmers, researchers involved in fields related to sheep farming and extension officers from private companies and public agencies. The investigation is based on data collected through self-administered questionnaires submitted to 165 participants to agricultural field days in Sardinia (Italy). The sample consists of sheep farmers (37,5%), researchers (16,4%), extension officers (32,1%) and other agricultural workers or students (14 %). In order to assess differences in attitude and identify the sources of attitudinal divergence, the study adopts Kolmogorov – Smirnov (KS) equality-of-distribution tests and Partial-least square structural equation modelling (PLS-SEM). Comparing and contrasting attitudes towards several topics related to GHG emission mitigation and adaptation to climate change reveal that researchers and extension officers have different attitudes towards innovation for mitigating GHG, that in turn depend on different information and beliefs on the causes and effects of climate change. This context is less than optimal to promote adoption of climate change mitigation or adaptation strategies. Climate change science and policy design need to recognise the complexity of knowledge transmission and the multiplicity of attitudes and beliefs that inform and affect the process. To mitigate the impact of diverging attitudes and beliefs among researchers and extension officers tailored communication strategies should avoid controversial issues and focus on benefits of innovation on farm efficiency. In turn, this would build trust and cooperation among all the actors in the knowledge transfer chain. Only when cooperation is assured, one could be confident that the information delivered to farmers is scientifically sound, relevant, value-neutral and useful in changing farmers' behaviour. [ABSTRACT FROM AUTHOR]

Impacts of commercial aircraft operation upon the environment, which are caused primarily from emissions of C O 2 , N O x and the formation of contrails, are matter of growing concern, as aviation is one of the fastest developing industrial sectors worldwide and the awareness of its effects is expanding. Recent research has focused on the cost-benefit potential of different mitigation strategies, which optimize flight trajectories with respect to climate and economy, but most of these mitigation strategies cannot be implemented in the near future due to technical challenges. The objective of this paper is to present an interim mitigation strategy, which bridges this time period. In analogy to military exclusion zones, climate restricted airspaces (CRA) are defined based on 3-D climate change functions, characterizing the environmental impact caused by an aircraft emission at a certain location. Regions with climate costs greater than a threshold value are closed in the corresponding month; others are cleared for air traffic. To estimate the cost-benefit potential of this strategy, a preliminary analysis is conducted on the route from Helsinki (EFHK) to Miami (KMIA). Affected flight trajectories are re-routed optimally around resulting CRA with regard to monetary costs for varying threshold values. Therefore, flight simulation algorithms are developed, which solve a non-linear optimal control problem. For each optimized flight trajectory corresponding average temperature response (ATR) and cash operating costs (COC) are expressed relative to a reference great circle trajectory with constant Mach number and compared with the climate mitigation potential of climate optimized trajectories. [ABSTRACT FROM AUTHOR]

The main objective of this study is to analyze and compare greenhouse gas emission profiles, dynamics thereof, and the climate change mitigation efforts of the major players in the global climate change arena, namely the G7 and BRICS countries that are accounting for more than 60% of the world greenhouse gas emissions as in 2017. Given that the energy sector is the major source of the greenhouse emissions in these countries, the framework of sustainable energy development indicators was applied to the comparative analysis. The analysis revealed the differences among the groups of countries in terms of greenhouse gas emission profiles and development trends of these profiles. The convergence of greenhouse gas emission profiles can be noticed between G7 and BRICS countries during 1990–2017 period. Greenhouse gas emissions per capita has decreased in G7 countries and increased in BRICS countries. Energy intensity, economic growth and carbon factor are the main drivers of greenhouse gas emissions per capita growth in both groups of countries. Carbon factor represents carbon intensity of a country's energy sector and is measured by greenhouse gas emissions per unit of total primary energy supply. The impact of carbon factor was least significant among the main drivers in both groups. Energy intensity was the major driver of decrease in greenhouse gas emissions per capita for both groups, however, the economic growth exceeded the contribution of energy intensity in BRICS countries and greenhouse gas emissions have increased in this group during investigated period. The comparative analysis of greenhouse gas emission profiles development trends and the main drivers of these trends in both groups of countries provides important insights in shaping future climate change mitigation policies and developing greenhouse gas emission reduction targets. Due to the high greenhouse gas profiles, low GHG reduction commitments and insufficient climate change mitigation the Perform, Achieve and Trade (PAT) scheme in India efforts in both groups there is danger of postponing implementation of Paris commitments and achieving the 1.5° target. The policies implemented in high ranked countries, like or Integrated Resources Planning in South Africa or measures under Energy efficiency directive in EU can be applied in low ranked countries by providing the substantial contribution to the country's climate targets. Image 1 • The GHG profiles of G7 and BRICS were converging during 1990–2017. • GHG/capita has decreased in G7 countries and increased in BRICS countries. • Energy intensity, economic growth and carbon factor - the main drivers of GHG/capita. • Energy intensity - the major driver of decrease in GHG/capita for both groups. • However, the economic growth exceeded the contribution of energy intensity in BRICS. [ABSTRACT FROM AUTHOR]

Decarbonisation strategies for eight German manufacturing companies of different industries (electrical, chemical, beverage, mechanical engineering, automotive, polymer processing) are developed and analysed. The abatement potential and economic feasibility of strategies depend to a large extent on individual preconditions e.g., the area available for renewable energy systems, and dynamic effects, for example the changing emission intensity of local electricity generation. The strategies lead to a reduction of between 41 % and 88 % for seven of the eight companies. The in-depth case studies show that energy efficiency measures and expanding the company's own renewable energy plants, except for solar heat, are particularly cost-effective, while shutting-down existing combined heat and power plants has the highest abatement costs between 169 and 1686 EUR/tCO 2 e. Decarbonising electricity procurement and switching from natural gas to biomethane have the highest greenhouse gas abatement potential in Scope 1 and 2. The novelty of this work is the linking of economic and ecological considerations of measures in the context of company-specific decarbonisation strategies. Using marginal abatement cost curves, different options for emission reductions are discussed and general conclusions for the development of decarbonisation strategies in the manufacturing sector are drawn. [Display omitted] • In-depth decarbonisation strategies are developed for eight manufacturing companies. • Abatement potential and economic feasibility depend largely on dynamic effects. • Energy efficiency and own renewable generation capacity are most cost-effective. • Marginal abatement cost curves link economic and ecological potential. • Greenhouse gas abatement costs are quantified for different industries. [ABSTRACT FROM AUTHOR]

The depth and breadth of the climate crisis is well known, all sectors, industry, government and the individual have the potential to reduce emissions to slow or stop catastrophic climate change. To determine and evaluate the (revealed) preferences of the public in reducing their personal carbon emissions, a conjoint analysis survey, using the PAPRIKA (Potentially All Pairwise RanKings of all possible Alternatives) method, was distributed to the public in a city in the south of England (Southampton). Knowledge of the deep-seated preferences of the public makes a fundamental contribution to future climate actions because it enables publicly acceptable system change to be developed. Results showed the public were unwilling to make large-scale lifestyle changes, even if they would cause large emission reductions. There was a clear preference for making relatively easy, convenient changes to behaviour rather than making more difficult personal lifestyle changes involving diet and transportation. A significant value-action gap is evident, with the public showing high awareness of the seriousness of climate change but showing an unwillingness to make deep cuts to their personal emissions. Demography and personal factors had a relatively low influence over preferences with trends generally staying the same across demographic groups, aside from income brackets. Participants believed that reductions in emissions should come from a 'group effort' from all levels of government, business, environmental groups and individuals. Few participants placed themselves as individual drivers of carbon emission reduction. In order to reduce emissions some form of intervention needs to be made, as the public are not personally willing to make large-scale reductions in carbon emissions, regardless of their environmental awareness or demography. • Public's views on approaches to carbon reduction investigated via conjoint analysis. • Preference for low intensity, 'easy' behaviours not challenging lifestyle changes. • Demographic & personal factors have low influence on carbon reduction preferences. • High awareness of severity of climate change, impacts/priority; also high anxiety. • Desire to consume & "carry on as normal" outweighs self-reported concerns/attitudes. [ABSTRACT FROM AUTHOR]

Reducing greenhouse gas emissions as a key mitigation strategy for climate change has become a global consensus. Remote work, which has good carbon footprint reduction potential, is widely considered a sustainable working mode. However, it is still unknown the extent to which occupations and means to work may influence the pathways of carbon footprint reduction from remote work when interacting with income groups of populations. This study investigates whether optimizing low-carbon scenarios centered on remote work in four major U.S. cities impacts inequality between high and low-income populations. Firstly, we employ an emissions coefficient methodology to quantify the per capita carbon footprint reductions achieved by remote workers within Census Block Groups (CBGs). Secondly, we estimate the decarbonization potential of remote work across urban areas, crafting an optimized scenario that strikes a balance between carbon footprint reduction objectives and urban economic development. This scenario entails transitioning a minimal number of workers from on-site to remote work. Lastly, we analyze the implications of this scenario on high and low-income groups. Our findings suggest that within the constructed low-carbon scenario, low-income individuals are predominantly employed in professions with limited remote work opportunities. Paradoxically, they shoulder a more substantial burden in terms of carbon reduction efforts, underscoring the challenges faced by low-income populations in diminishing their carbon footprints. Consequently, our study offers fresh empirical insights for researchers and policymakers to evaluate the equity aspect of remote work's carbon reduction potential, highlighting the disproportionate challenges faced by low-income groups. In formulating remote work carbon footprint reduction strategies, it is crucial to strike a balance between carbon footprint reduction allocation and other socio-economic costs, while also exploring feasible pathways and actions to attain these goals. [Display omitted] • Leverage remote work as an urban carbon footprint reduction measure. • Cities rely on car commuting have better carbon reduction potential for remote work. • Low-income populations bear more burden in telework carbon reduction process. • The decarbonization process needs to consider the impact of low-income populations. [ABSTRACT FROM AUTHOR]

• Middle-aged forests in the Eastern U.S. have attained about half of their potential carbon stocks. • Most Eastern U.S. forests could continue to accumulate carbon for many decades or several centuries in the absence of harvesting, with relatively low risk of natural disturbances. • In the near term of 20–40 years, reducing harvest will yield the greatest reduction in greenhouse gases compared with business as usual. • How middle-aged forests in the Eastern U.S. are managed can clearly affect their contribution to achieving net-zero GHG emissions by 2050 and beyond. • Our estimated emission reduction from stopping harvest over the 73 million ha studied amounts to 117 Mg CO 2 per year in 2050, equivalent to about 7% of the emissions from using fossil energy in the two ecozones. Increasing harvest would have the opposite effect of increasing emissions by a similar magnitude. • In the longer term of 80 or so years, scenarios converge towards business-as-usual effects on greenhouse gases, but with differences between and within biomes. • The contrast between short- and long-term impacts of different harvest levels is an important consideration for designing land management policies. Middle-aged forests in the Eastern U.S. are broadly defined to consist of forests between the regeneration phase following harvest or disturbance, and an older phase with forests composed of large trees, complex structure, and increasing natural mortality. Study objectives were to develop new carbon accumulation curves based on recent inventory data that represent the actual growth rates of forests as they advance beyond middle age; quantify the projected carbon sink from reducing or increasing harvest of middle-aged forests; and disseminate credible estimates of future carbon stocks in ecosystems and harvested wood products to support policies designed to enhance the role of forests in removing carbon dioxide from the atmosphere and storing it securely. We found that middle-aged Eastern U.S. forests could continue to accumulate carbon for many decades or several centuries in the absence of harvesting, with relatively low risk of natural disturbances. Compared with a recent study that estimated a potential increase in biomass of only 22%, and some analyses that anticipate significant increases in risks from natural disturbances, our results indicate a potential increase of about 100% over current biomass stocks by 2100. Temperate Continental forests have greater potential to increase carbon stock over longer time periods than Subtropical Humid forests. Results from scenario analyses showed that in the near term of 20–40 years, reducing harvest will yield the greatest reduction in net greenhouse gas emissions compared with business as usual. Under an extreme "no-harvest" scenario, C sequestration could increase by about 20 TgC yr−1 in Temperate Continental forests by 2050, and by about 30 TgC yr−1 in Subtropical Humid forests over the same time period. In contrast, a scenario of tripling harvest would increase C emissions by 30 and 60 TgC yr−1 in the Temperate Continental and Subtropical Humid ecozones by 2050, respectively. In the longer term of 80 or so years, all scenarios and "business as usual" converge toward similar impacts on greenhouse gas emissions, nearing neutrality in the Subtropical Humid ecozone but separated by about 30 TgC yr−1 in the Temperate Continental ecozone. Our estimated annual emission reduction from stopping harvest over the 73 million ha of middle-aged forests amounts to 117 Mg CO 2 per year in 2050, equivalent to about 7% of the emissions from using fossil energy in the two ecozones. Increasing harvest would have the opposite effect of increasing emissions by a similar magnitude in 2050. How middle-aged forests in the Eastern U.S. are managed can clearly affect their contribution to achieving net-zero GHG emissions by 2050 and beyond. [ABSTRACT FROM AUTHOR]

Deep decarbonization scenarios indicate a decline in fossil oil usage in the coming decades, meaning that oil refineries must adapt. This work evaluates the refining sector in deep decarbonization pathways using Brazil as a case study. BLUES – a national integrated assessment model – is employed to investigate the evolution of the sector in mitigation scenarios until 2050. The production of feedstocks for the petrochemical industry, of fuels for the aviation and maritime sectors, and biomass co-processing are analyzed. These strategies may bring resilience to the sector. The potential for avoiding emissions in refineries' operations is also explored. Findings show that the refining sector operates at 70% and 74% of its nameplate capacity in decarbonization scenarios. These results are used as the starting point for a detailed analysis of Brazilian refineries. Results show that the employment of refineries' assets for purposes aligned with decarbonization targets, along with emissions mitigation in the sector, reduces risks of carbon lock-in and of asset stranding. To our knowledge, this is the first study that evaluates emissions mitigation in the refining sector and also uses an integrated assessment model to investigate oil refining repurposing and co-processing options in the context of decarbonization. • The refining sector is evaluated using an integrated assessment model for Brazil. • A comparison is made between business- as -usual and decarbonization scenarios. • Opportunities for refineries' assets and mitigation measures are explored. • Opportunities for refineries depend on their location and type of processing units. • Risks of carbon lock-in and asset stranding can be reduced. [ABSTRACT FROM AUTHOR]

Rapidly increasing catastrophic environmental incidents and changes in global climate have compelled researchers to take proactive measures for climate change mitigation. Consequently, reducing greenhouse gas emissions has become one of the most significant global targets. The transportation sector has a massive carbon footprint accounting for 22% of the total carbon dioxide emissions. In this regard, road transport contributes the largest fraction of the total emissions within the transportation sector. Conversely, the railway which is the cleanest form of transportation contributes slightly more than 1% of the total emissions. Moreover, since most of the rail systems are operated by government or private companies, it is relatively convenient to implement policies and replace conventional technology with environmentally friendly ones. This could be achieved by taking certain measures from technical and operational viewpoints for conserving energy to lower the carbon intensity of all transport modalities. Hence, this review paper focuses on investigating the railway sector to encourage a modal shift to the least carbon-intensive option. This study provides a critical review of the past and present rail technologies in terms of the environmental, economic, social, and technical perspectives. Moreover, a comparative assessment of the various locomotive types has been performed. The results reveal that battery-hydrogen hybrid locomotives are the best choice to be considered as a future locomotive technology. Hydrogen locomotives have the potential to be a promising alternative to diesel railway locomotives. However, certain technical barriers need to be overcome to enhance the overall system's performance and reliability to further improve the viability of its deployment in the railway sector. [Display omitted] • A critical review of the various rail technologies is provided through different viewpoints. • The assessment constitutes environmental, economic, social, and technical perspectives. • A decision-support tool for comparison of four rail technologies is also developed. • Battery-hydrogen hybrid locomotive results in the highest score of 1.47. • Standalone hydrogen locomotive results in the second highest score of 1.38. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the decoupling status and mitigation potential of CO2 emissions from China's transport sector over the period 1991–2015. Firstly, this paper utilizes the Log-Mean Divisia Index (LMDI) technique to identify influencing factors, which govern CO2 emissions from China's transport sector. Over the study period, the CO2 coefficient effect (Δ C c f t ) was the main factor for decreasing CO2 emissions. However, the economic growth effect (Δ C g t ) was the main factor for increasing CO2 emissions. Then, the decoupling indicator is also constructed based on the above influencing factors, which can be utilized to reflect the dependence degree of economic development on CO2 emissions from China's transport sector. During 1991–2015, the CO2 emissions from China's transport sector presented expansive coupling (EC) with economic development. Weak decoupling (WD) only appeared in the sub-period 1991–1995. The CO 2 emissions only presented 3 decoupling grades in all sub-period and the period 1991–2015: Ⅱ, Ⅲ, and Ⅳ. Furthermore, the above influencing factors are also used to establish a theoretical mitigation model, which is used to reflect the mitigation potential of CO2 emissions from China's transport sector. Finally, the occurrence of CO2 mitigation only appeared in 3 sub-periods: 1991–1995, 2005–2010, and 2010–2015. • The LMDI technique is used to identify influencing factors. • The decoupling indicator is constructed based on the influencing factors. • The influencing factors are used to establish a theoretical mitigation model. [ABSTRACT FROM AUTHOR]