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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]

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]

Food systems contribute 23–42% of global greenhouse gas emissions. Reducing food system emissions is an essential component of climate change mitigation, and a system-wide approach, including production, processing, trade and demand-side transformations, will be needed. Long-term analysis of greenhouse gas (GHG) emissions of food supply is crucial for informing this transformation, and understanding the processes contributing to existing trends can reveal opportunities for future mitigation strategies. To address these needs we used data on food supply, trade and emission intensity to quantify changes in GHG emissions between 1986 and 2017 resulting from food supply in the United Kingdom (UK). Uniquely, the relative contributions of supply-side and demand-side changes to historical trends in food emissions were assessed, and the gap between current UK food consumption and EAT-Lancet recommended diets was used to estimate the additional GHG emission reductions that could be achieved by shifting to the Planetary Health Diet (PHD). It was estimated that in the UK, per-capita GHG emissions from food fell by 32% (from 4.6 tCO 2 eq/capita to 3.1 tCO 2 eq/capita) between 1986 and 2017. Of this 32% reduction, 21% was due to supply-side changes (a fall in emission intensity per unit of production due to increased efficiency of farming practices), 10% was due to demand-side changes (including dietary change and waste reduction), and 2% was due to changing trade patterns. Relative to the PHD, however, the average UK citizen still greatly over-consumes beef, lamb and pork, tubers and starchy vegetables and dairy products, and under-consumes vegetables, nuts, and legumes. It was estimated that by adopting the PHD, UK per capita food emissions could be reduced by a further 42% to 1.8 tCO 2 eq/capita. These results expose the historic contributions of both supply- and demand-side changes to reductions in GHG emissions from food, and highlight the underutilised potential of dietary change in contributing to mitigation of GHG emissions from food. [Display omitted] • UK per-capita food emissions fell by 32% between 1986 and 2017. • Supply and demand-side changes contributed to this reduction. • Adopting the Planetary Health Diet could reduce emissions of UK food supply by 42%. • This reveals the underutilised potential of dietary change as a mitigation strategy. [ABSTRACT FROM AUTHOR]

Biomass plays a dual role as an energy source and a solution for climate change mitigation. There are complexities surrounding decentralized electricity generation, and Ghana could not achieve its 10% renewable energy target in 2020. The paper assesses the greenhouse gas mitigation potential and economic impact of electricity from major food crop residues subjected to anaerobic digestion technology in 16 regions and 88 districts in Ghana from 2017 to 2020. Buswell equation was applied to calculate the biogas and methane yield. The environmental impact assessment was expressed as global warming potential, and the economic feasibility was conducted. The results showed that crop residues' annual theoretical and technical potential was 28.92 Mt and 17.24 Mt. The top four residues with the largest share of technical potential were maize (5.41 Mt), yam (3.58 Mt), plantain (3.05 Mt) and cassava (2.39 Mt). Biogas and electricity potentials were 1,912.74 Mm3 and 3,068.34 GWh, which could offset 15.56% of electricity consumption in Ghana. The Ashanti (478.18 GWh), Eastern (430.20 GWh), Bono East (318.29 GWh) and Northern (314 GWh) regions demonstrated the highest electricity potential. Ghana could generate the highest electricity potential of 46.52 GWh in the districts and a minimum potential of 0.89 GWh annually. Power generation potential from anaerobic digestion had a diesel displacement capacity of 923.35 × 10 6 L with a GHG emissions reduction of 2,507.35 kt CO 2 eq. The largest GHG reduction potential was 38.15 kt CO 2 eq at the district level. The findings show that the project is economically viable, with an average net present value of $ 10,105,904 per region and an electricity cost of $ 0.0321/kWh. The study provides critical insights to policymakers and industry developers for decentralized biomass-based electricity generation in Ghana. • A sustainable crop residue assessment is conducted in Ghana. • The total biogas-based electricity is 3,068.34 GWh. • Ashanti region has high electricity (478.18 GWh) than Greater Accra (9.82 GWh). • The total GHG mitigation is estimated as 2507.35 kt CO 2 eq. • The project is economically viable at a cost of $ 0.0321/kWh. [ABSTRACT FROM AUTHOR]

To translate scientific evidence into policy decisions, a universal, integrate and rapid–calculation model is needed for estimating the air quality associated health co–benefits of climate change mitigation strategies. This study developed such a greenhouse gas policy assessment model (GHG–PAM) based upon the annually published energy balances tables. To examine the applicability of this model, we select Suzhou, one of the national low-carbon pilot cities located in the east of China, as a case study. It was determined that carbon dioxide (CO 2 ) emissions in Suzhou would increase from 148 million tons in 2010 to 297, 284, 180, and 173 million tons in 2020 under Business As Usual (BAU), Industrial Structure Dominated (ISD), Technology Dominated (TD), and Integrate Carbon Reduction (ICR) scenarios, of which only ICR scenario meets its carbon intensity target. Under the ICR scenario, the implementation of greenhouse gas policies reduces the air pollution associated burden of diseases, measured by Disability-Adjusted Life Years (DALY), by 44.1% in 2020 compared to BAU, although even with this scenario the burden of diseases would still be higher than that in 2010. In addition, the model can also identify sectors and industries with greater health co–benefits per unit CO 2 emission reduction, which provides a useful guide for Suzhou's climate policy makers to formulate cost–effective measures. However, it should be carefully used where there is a mismatch between sectors with high potential for CO 2 emission reductions and sectors with high health co–benefits per unit CO 2 emission reduction. [ABSTRACT FROM AUTHOR]

Cities are a major source of greenhouse gas emissions (GHGs), but they can play a significant role in climate change mitigation by adopting and implementing GHG emission reduction plans, policies and measures. Circular economy measures are recognized to contribute significantly to decarbonization. However, in the literature there is a lack of quantitative analyses on circular measures in cities and their impact on urban GHG emissions. The paper aims to contribute to the literature on the relation between circular cities and climate change mitigation by focusing on circular interventions applicable in three high-impact sectors in cities: energy systems, mobility and built environment, in order to investigate their impacts in terms of emission reductions and contribution to decarbonization. The study covers four cities around the world accounting for more than 10 million of inhabitants and 2,000 km2 of metropolitan area: Bogotá, Colombia; Genoa and Milan, Italy; Glasgow, UK. The methodology uses a Global Trade Analysis Project (GTAP) modelling approach to develop production and consumption-based emission baselines for the four cities and to assess impacts of selected circular measures in the three sectors on the baselines. According to the in-depth analysis of the four considered urban contexts, the majority of the emissions generated by activities carried out within the urban borders are emitted outside the borders in the form of emissions scope 3, thus demonstrating how today's cities are large consumers of goods produced outside their borders, requiring the use of a consumption-based approach for emissions inventory. The results on the modelling of the GHG reduction impact of circular measures show that there is a relevant emission reduction potential in Scope 1 and 2 emissions in cities and highlight the need to prioritize decarbonization of electricity supply in order to ensure relevant emission reductions across the three sectors. The results also demonstrate the potential to reduce supply-chain Scope 3 emissions through urban measures. [Display omitted] • Four different urban contexts around the world are taken in account. • Three sectors are investigated: energy, mobility and built environment. • A consumption-based emission accounting method is used to assess the effective impact of cities. • Impacts of different GHG emission reduction interventions are evaluated for each city. [ABSTRACT FROM AUTHOR]

Cities are a major source of greenhouse gas emissions (GHGs), but they can play a significant role in climate change mitigation by adopting and implementing GHG emission reduction plans, policies and measures. Circular economy measures are recognized to contribute significantly to decarbonization. However, in the literature there is a lack of quantitative analyses on circular measures in cities and their impact on urban GHG emissions. The paper aims to contribute to the literature on the relation between circular cities and climate change mitigation by focusing on circular interventions applicable in three high-impact sectors in cities: energy systems, mobility and built environment, in order to investigate their impacts in terms of emission reductions and contribution to decarbonization. The study covers four cities around the world accounting for more than 10 million of inhabitants and 2,000 km2 of metropolitan area: Bogotá, Colombia; Genoa and Milan, Italy; Glasgow, UK. The methodology uses a Global Trade Analysis Project (GTAP) modelling approach to develop production and consumption-based emission baselines for the four cities and to assess impacts of selected circular measures in the three sectors on the baselines. According to the in-depth analysis of the four considered urban contexts, the majority of the emissions generated by activities carried out within the urban borders are emitted outside the borders in the form of emissions scope 3, thus demonstrating how today's cities are large consumers of goods produced outside their borders, requiring the use of a consumption-based approach for emissions inventory. The results on the modelling of the GHG reduction impact of circular measures show that there is a relevant emission reduction potential in Scope 1 and 2 emissions in cities and highlight the need to prioritize decarbonization of electricity supply in order to ensure relevant emission reductions across the three sectors. The results also demonstrate the potential to reduce supply-chain Scope 3 emissions through urban measures. [Display omitted] • Four different urban contexts around the world are taken in account. • Three sectors are investigated: energy, mobility and built environment. • A consumption-based emission accounting method is used to assess the effective impact of cities. • Impacts of different GHG emission reduction interventions are evaluated for each city. [ABSTRACT FROM AUTHOR]

This study aims to forecast greenhouse gas (GHG) emissions in Hong Kong with an optimal selection of predictors. A review is made on the time-series of the GHG emissions by different sources in 1992–2021. Twenty potential predictors are examined relating to economics, social developments, energy use, waste production and climatic conditions, based on previous studies on GHG emissions and mitigation. Three principal components produce well-fitting linear-log regression models. The model stability over time is verified by expanding window analysis. The model accuracy is assured by a CV(RMSE) of 6.1508% in the testing sets. Based on hierarchical clustering and stepwise regression, the gross floor area of construction projects is the most significant predictor to forecast GHG emissions, followed by the unemployment rate and the total expense in construction works. High levels of the three predictors facilitate GHG mitigation, but cannot meet the carbon neutral target. Carbon reduction technologies should be strengthened in growing construction projects. Electricity related carbon mitigation should be further enhanced. The novelty of this study is to provide insights to updating and prioritizing decarbonization strategies in the next phase of Hong Kong's Climate Action Plan. • The peak and downward trend of GHG emissions are examined in Hong Kong. • Principal components produce well-fitting linear-log regression models with social and economic variables. • Significant predictors to forecast GHG emissions are identified from hierarchical clustering and stepwise regression. • Construction is the top priority in GHG mitigation. • Mitigating electricity-related GHG emissions facilitates meeting carbon neutrality. [ABSTRACT FROM AUTHOR]

Transforming and expanding the electricity sector are key for climate change mitigation and alleviation of energy poverty. Future energy systems based on renewable energy sources may reduce greenhouse gas (GHG) emissions but could require more materials during construction. We assess this trade-off by quantifying the requirements of the main bulk materials used in electricity infrastructures for 281 global electricity sector pathways until 2050. We identify main determinants for material requirements and gauge the relevance of socio-economic framework conditions and climate change mitigation regimes. Five selected, highly diverse scenarios are analysed in detail by quantifying their respective annual material stocks and flows, and cumulative GHG emissions to 2050. We find robust evidence that scenarios in line with the 1.5 °C target are associated with significantly higher material requirements than scenarios exceeding a global temperature rise of 2 °C. Material stocks in 2050 differ by up to 30% for copper, 100% for concrete, 150% for iron/steel and 260% for aluminium (3rd quartiles of Monte Carlo simulations), even when the particularly material-intensive "Below 1.5 °C″ scenarios are excluded. Although power plants account for the largest part of the material requirements, grid expansion and reinforcement, necessary to accommodate large shares of volatile power generation and provide universal access to electricity, also cause substantial material demand. In the absence of future GHG mitigation in the processing industries, GHG emissions related to bulk materials (primarily iron/steel and aluminium) could amount to one tenth of the remaining carbon budget for a 50% chance of limiting global warming to 1.5 °C. However, if preference is given to material-efficient technologies, low-carbon processes are applied in the industries and increased material recycling is achieved, GHG emissions related to bulk materials in decarbonisation pathways will not significantly exceed those in largely fossil fuel-based scenarios. • Global electricity sector pathways to 2050 require large amounts of bulk materials. • High-renewable scenarios that meet climate targets are most material-intensive. • Future iron/steel and aluminium requirements imply large greenhouse gas emissions. • Without mitigation, cumulative GHG emissions could be 10% of the 1.5° carbon budget. • Mitigation options include material efficiency, technology development & circularity. [ABSTRACT FROM AUTHOR]

Rural development projects to develop sustainable agriculture need to be assessed before engaging smallholder farmers at large scale. Data on agricultural systems to produce food, provide income for smallholders and reduce greenhouse-gas (GHG) emissions are scarce in Sub-Saharan Africa countries. Here, we assessed the potential of agroecological practices (AP) on economic benefits to farmers, GHG balance derived from agricultural activities, and efficiency of economic investments to mitigate GHG. The study was based on a NGO rural development project, which promoted AP: agroforestry, compost, and System of Rice Intensification. The economic and GHG mitigation benefits were projected over a period of 20 years on three scenarios. Two scenarios, differing by two expected levels of AP adoption, were compared to a reference one, in which there was no NGO intervention. Socio-economic, yield and soil data were gathered on 192 farms during five growing seasons (2013–2018). The GHG balance was estimated with TropiC Farm Tool and EX-ACT. The GHG emissions were reduced in both scenarios compared to the reference one: −5.2 to −13.6 tCO 2 eq farm−1 yr−1 for scenario 1 and 2 respectively. At the regional scale, the projected amount of C saved per euro invested was estimated at −0.25 tCO 2 eq euro−1 and -0.41 tCO 2 eq Euro−1 (or € 4 to 2.5 tCO 2 eq−1) under scenario 1 and scenario 2. The annual cash flow of farmers increased over the 20 years. Our study highlighted the potential of AP for increasing productivity and profitability of smallholder agricultural systems for the Malagasy farmers, while simultaneously contributing to climate change mitigation. Image 1 • Ex-Act and TropiC Farm Tool assess greenhouse gas balance of farms and development project. • Both tools predicted similar 20-year trends in reductions of greenhouse gas balances. • Agroecological practices increased productivity and profitability of farmers. • Over 20-year period the project is projected to sequester 3.7tCO 2 eq per euro invested. [ABSTRACT FROM AUTHOR]