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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]

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]

• 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]

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]

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]

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]

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]

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]

• 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]

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]

• 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]

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]