A Dynamic Material Flow Model for Risk-Informed Decision Making in Decarbonizing Global Aluminum Manufacturing

Agriculture is responsible for a large share of global greenhouse gas (GHG) emissions, especially for methane and nitrous oxide emissions. Applying a bio-economic whole-farm model, we assessed five GHG mitigation options on their economic suitability to reduce emissions from grassland-based suckler cow farms. Among the assessed options, only compensation by agroforestry systems and the choice of an adequate production system showed the potential to significantly reduce emissions. If an adequate production system is chosen, GHG emissions per kilogram of meat can be reduced by up to 18% – from 21.9 to 18 kg CO2-eq./kg of meat – while total gross margin can be increased by up to 14%. Through the application of an agroforestry system, GHG emissions in all systems can be further reduced to 7.5 kg CO2-eq./kg meat – equating to a reduction of GHG emissions of 48% to 66% – at costs between 0.03 CHF/kg meat and 0.38 CHF/kg meat depending on the production system and the state of the system before the reduction. In contrast, the addition of lipids to the diet or a cover to the slurry tank has neither the potential to reduce GHG emissions significantly nor are they cost-effective enough to be implemented. Nitrification inhibitors can reduce GHG emissions up to 10%, but costs for this reduction are much higher than for agroforestry systems. The application of agroforestry systems to suckler farming in Switzerland therefore seems to be an adequate option to reduce GHG emission significantly for a relatively low price.

This paper examined the determinants (decomposed into enablers and de-enablers) of global greenhouse gas (GHG) emissions to deepen the debate on enhancing the implementation of the social cost of carbon or carbon pricing. Data from world development indicators were utilized in this study. The study leverages the autoregressive distributive lag model, pairwise granger causality, and impulse response function tests. This study found that there is a long-run relationship between selected economic indicators and GHG emissions in the global economy. In the long run, the GHG emissions enablers are FDI inflow and fossil fuel consumption. On the other hand, de-enablers of GHG emissions are GDP growth rate and merchandise trade. However, gas, oil, and coal use for electricity and fertilizer consumption have mixed finding across the regions. Also, the study observed that there exists no causality between GHG emissions and selected finance-related variables. A 1% shock in GHG emissions generates monetary volatility. Based on the findings that global trade generates a similar impact on GHG emissions across high-income countries, low-income countries, and middle-income countries. This study recommends the imposing of carbon tax and cap-and-trade on the GHGs polluting sectors and countries involved in the production and distribution of economic goods (activities) enabling GHG emissions.

Abstract. To track progress towards keeping global warming well below 2 ∘C or even 1.5 ∘C, as agreed in the Paris Agreement, comprehensive up-to-date and reliable information on anthropogenic emissions and removals of greenhouse gas (GHG) emissions is required. Here we compile a new synthetic dataset on anthropogenic GHG emissions for 1970–2018 with a fast-track extension to 2019. Our dataset is global in coverage and includes CO2 emissions, CH4 emissions, N2O emissions, as well as those from fluorinated gases (F-gases: HFCs, PFCs, SF6, NF3) and provides country and sector details. We build this dataset from the version 6 release of the Emissions Database for Global Atmospheric Research (EDGAR v6) and three bookkeeping models for CO2 emissions from land use, land-use change, and forestry (LULUCF). We assess the uncertainties of global greenhouse gases at the 90 % confidence interval (5th–95th percentile range) by combining statistical analysis and comparisons of global emissions inventories and top-down atmospheric measurements with an expert judgement informed by the relevant scientific literature. We identify important data gaps for F-gas emissions. The agreement between our bottom-up inventory estimates and top-down atmospheric-based emissions estimates is relatively close for some F-gas species (∼ 10 % or less), but estimates can differ by an order of magnitude or more for others. Our aggregated F-gas estimate is about 10 % lower than top-down estimates in recent years. However, emissions from excluded F-gas species such as chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs) are cumulatively larger than the sum of the reported species. Using global warming potential values with a 100-year time horizon from the Sixth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), global GHG emissions in 2018 amounted to 58 ± 6.1 GtCO2 eq. consisting of CO2 from fossil fuel combustion and industry (FFI) 38 ± 3.0 GtCO2, CO2-LULUCF 5.7 ± 4.0 GtCO2, CH4 10 ± 3.1 GtCO2 eq., N2O 2.6 ± 1.6 GtCO2 eq., and F-gases 1.3 ± 0.40 GtCO2 eq. Initial estimates suggest further growth of 1.3 GtCO2 eq. in GHG emissions to reach 59 ± 6.6 GtCO2 eq. by 2019. Our analysis of global trends in anthropogenic GHG emissions over the past 5 decades (1970–2018) highlights a pattern of varied but sustained emissions growth. There is high confidence that global anthropogenic GHG emissions have increased every decade, and emissions growth has been persistent across the different (groups of) gases. There is also high confidence that global anthropogenic GHG emissions levels were higher in 2009–2018 than in any previous decade and that GHG emissions levels grew throughout the most recent decade. While the average annual GHG emissions growth rate slowed between 2009 and 2018 (1.2 % yr−1) compared to 2000–2009 (2.4 % yr−1), the absolute increase in average annual GHG emissions by decade was never larger than between 2000–2009 and 2009–2018. Our analysis further reveals that there are no global sectors that show sustained reductions in GHG emissions. There are a number of countries that have reduced GHG emissions over the past decade, but these reductions are comparatively modest and outgrown by much larger emissions growth in some developing countries such as China, India, and Indonesia. There is a need to further develop independent, robust, and timely emissions estimates across all gases. As such, tracking progress in climate policy requires substantial investments in independent GHG emissions accounting and monitoring as well as in national and international statistical infrastructures. The data associated with this article (Minx et al., 2021) can be found at https://doi.org/10.5281/zenodo.5566761.

Prediction of GHG emissions from Chengdu Metro in the construction stage based on WOA-DELM

Agricultural transformation towards delivering deep carbon cuts in China’s arid inland areas

Agriculture accounts for a large proportion of global greenhouse gas (GHG) emissions. It is therefore crucial to identify effective and efficient GHG mitigation potentials in agriculture, but also in related upstream sectors. However, previous studies in this area have rarely undertaken a cross-sectoral assessment. There is also a gap in research on the GHG mitigation potential of innovations such as green ammonia in arable farming at a larger spatial scale. The study therefore aimed to analyze how selected technological adaptations or innovations can be used to contribute to efficient and effective cross-sectoral GHG mitigation in conventional arable farming systems. Germany, one of the largest agricultural producers and contributors of GHG emissions from agriculture in the EU, was chosen as a case study. The GHG mitigation potential and abatement cost of four selected measures were analyzed using an integrated land use model and life cycle assessment. Their GHG mitigation potential varied between 0.3Mt CO2-eq. for nitrification inhibitors under lower mitigation rate assumptions and 4.7Mt CO2-eq. for green ammonia with upper mitigation rate assumptions on GHG emission impacts, i. e. rather high mitigation. While crop varieties based on new genomic technologies (NGT) were introduced at no GHG abatement cost, the average mitigation costs ranged from 48 € for the use of nitrification inhibitors (upper mitigation rate) to 1233 € per t CO2-eq. for N sensors (lower mitigation rate). There were also regional differences due to different land use structures, regional farm sizes, economic and agronomic conditions. Based on these results we recommend for agricultural and environmental policy to foster the use of nitrification inhibitors due to the identified GHG reduction potential and the comparatively low GHG abatement costs. Additionally, the use of green ammonia in fertilizer production should be further promoted. Although the results are exemplary for Germany, they can be very informative for other EU Member States with comparable socio-economic and agronomic conditions.

Milk and beef production cause 9% of global greenhouse gas (GHG) emissions. Previous life cycle assessment (LCA) studies have shown that dairy intensification reduces the carbon footprint of milk by increasing animal productivity and feed conversion efficiency. None of these studies simultaneously evaluated indirect GHG effects incurred via teleconnections with expansion of feed crop production and replacement suckler-beef production. We applied consequential LCA to incorporate these effects into GHG mitigation calculations for intensification scenarios among grazing-based dairy farms in an industrialized country (UK), in which milk production shifts from average to intensive farm typologies, involving higher milk yields per cow and more maize and concentrate feed in cattle diets. Attributional LCA indicated a reduction of up to 0.10kg CO2 e kg-1 milk following intensification, reflecting improved feed conversion efficiency. However, consequential LCA indicated that land use change associated with increased demand for maize and concentrate feed, plus additional suckler-beef production to replace reduced dairy-beef output, significantly increased GHG emissions following intensification. International displacement of replacement suckler-beef production to the "global beef frontier" in Brazil resulted in small GHG savings for the UK GHG inventory, but contributed to a net increase in international GHG emissions equivalent to 0.63kg CO2 e kg-1 milk. Use of spared dairy grassland for intensive beef production can lead to net GHG mitigation by replacing extensive beef production, enabling afforestation on larger areas of lower quality grassland, or by avoiding expansion of international (Brazilian) beef production. We recommend that LCA boundaries are expanded when evaluating livestock intensification pathways, to avoid potentially misleading conclusions being drawn from "snapshot" carbon footprints. We conclude that dairy intensification in industrialized countries can lead to significant international carbon leakage, and only achieves GHG mitigation when spared dairy grassland is used to intensify beef production, freeing up larger areas for afforestation.

The healthcare sector contributes significantly to global greenhouse gas (GHG) emissions, with anaesthetic gases being a notable contributor. Implementing sustainable practices in equine anaesthesia, such as low-flow anaesthesia, offers potential benefits. To audit oxygen and isoflurane usage in five equine hospitals, their associated GHG emissions, and the impact of anaesthesia training on mitigating these emissions. Multi-centre clinical audit. This audit covered two periods: study period one (1 June-30 September 2022) and study period two (1 June-30 September 2023). After period one, an anaesthesia training programme introduced low-flow techniques. Data collected retrospectively included patient signalment, anaesthetic protocol, and 5-min recordings of fresh gas flow (FGF) and vapouriser settings. GHG emissions (in carbon dioxide equivalents) and costs (in £) were calculated. Statistical analysis used a linear mixed-effects model with a significance level of p-value <0.05. A total of 414 general anaesthetics were audited. Between study period one and two, isoflurane and oxygen usage decreased by 9.6% and 17.9%, respectively, resulting in a 9.6% reduction in GHG emissions (from 14.6 to 13.2 tCO2e). A linear mixed-effects model identified five significant predictors of GHG emissions per case: study period, oxygen usage, anaesthesia duration, average isoflurane vapouriser setting, and the interaction between oxygen usage and study period. Cases in study period two were associated with lower GHG emissions, producing on average 10.4 kgCO2e less per case (p = 0.01), while each additional litre of oxygen consumed increased emissions by 0.12 kgCO2e (p < 0.001). Missing data from FGF and/or vapouriser settings and the minimal variability between hospitals could be perceived as limitations. This audit demonstrates that practising low-flow anaesthesia can effectively reduce the environmental impact of inhalant anaesthetic agents during equine anaesthesia. Wider adoption could improve sustainability, although further research and broader professional engagement are needed.

The number of emission trading and carbon taxation schemes implemented has grown rapidly over the past decade. Together, they cover approximately 16% of global greenhouse gas (GHG) emissions. Although more than two-thirds of global GHG emissions are related to household consumption, approaches that directly target households, such as personal carbon trading (PCT), do not play a role in the fight against climate change. This is especially puzzling as measures taken so far are not sufficient to reach the 2 °C target. One clue to solving this puzzle comes from political science in the form of the multiple streams approach, which defines criteria that a policy proposal must meet to become part of the political agenda. Based on these criteria, this article conducts a systematic review on PCT to clarify why PCT does not play a role in the reduction of GHG emissions. The results show that there are three main problems with the PCT proposal. First, scholars often criticize the set-up costs as well as the running costs of such a system. Second, there is no clear consensus within the research community on public acceptance of PCT. Third, it is still unclear whether politicians are receptive to PCT or not.

Background The dairy industry is a growing contributor to global greenhouse gas (GHG) emissions, primarily through methane and nitrous oxide release. Historically, climate mitigation efforts have prioritised fossil fuel reduction, but the substantial environmental impact of dairy production is now increasingly recognised. Aims and Scope This review synthesises global studies from 2004 to 2025 on GHG emissions in the dairy industry, focussing on developing countries. It presents promising technologies for dairy GHG abatement, identifies key implementation barriers and outlines research priorities to guide sustainable practices. Method A systematic literature review was conducted using Scopus, Web of Science, and PubMed, prioritising peer‐reviewed studies on dairy GHG emission quantification and mitigation technologies. Major Findings Anaerobic digestion (AD) is identified as the most promising mitigation technology, capable of reducing methane emissions by 50–70% while producing renewable biogas and organic fertiliser. Co‐digestion can increase biogas yields by 10–30% through enhanced carbon‐to‐nitrogen balance. It offers a scalable, sustainable waste‐to‐energy solution to dairy GHG emissions. 3‐Nitrooxypropanol (3‐NOP) feed additives demonstrate up to 40% methane reduction in controlled settings. However, its widespread adoption faces significant hurdles, including regulatory approval processes varying by region, consumers' food safety concerns and practical on‐farm implementation challenges. Despite the availability of multiple mitigation strategies, implementation in developing countries remains constrained by capital costs, technical expertise and infrastructure gaps. Overcoming these barriers is essential to unlock the global potential of these technologies for meaningful dairy sector decarbonisation. Scientific Implications Effective GHG mitigation in the dairy sector requires integrated, region‐specific solutions. Targeted policy support, public–private partnerships and access to carbon finance are essential for scaling technologies such as AD. Broader adoption of mitigation tools, combined with sustainable manure and feed management practices, will be vital to achieving climate targets in both developed and developing economies.

Global greenhouse gas (GHG) emissions from gold mining exceed 100 Mt CO2-e annually, with country emissions intensity from 129 to 2754 kg CO2-e/oz, yet clear knowledge gaps remain regarding country contributions, emissions reduction potential, and impact of carbon pricing. The cost impacts upon global gold miners of the introduction of a hypothetical US$50/t CO2-e and US$100/t CO2-e carbon price are quantified and are affordable. Carbon price impacts vary markedly between countries, with a US$100/t CO2-e price increasing gold production costs on average by US$13 per ounce in Finland and up to US$275/oz in South Africa. The research method aggregated 2018 mine-specific GHG emission and production data to the country level, allowing carbon price impacts to be quantified. Global adoption of carbon pricing changes the relative cost competitiveness of countries, having policy implications. Clean energy substitution and energy efficiencies, including new mining technologies, are at the forefront of the gold sector responses to reduce emissions. The reduction in GHG emissions from energy substitution of the mine's primary energy source is up to 46%. The most significant reductions in GHG emissions from energy efficiencies are in underground mines from ventilation and cooling, up to 24%. Gold companies that reduce their carbon footprint benefit from a lower cost of capital. Clear potential exists for a shift towards a cleaner, decarbonised global gold industry.

The healthcare sector is responsible for 4-5% of global greenhouse gas (GHG) emissions, not only from hospitals but also from other health and care entities, which contribute approximately 50% of these emissions. Without intervention, the projected annual GHG emissions from the healthcare sector are expected to dramatically increase by 2050. Traditionally, health and care facilities, including hospitals, have prioritized patient care and safety over operational costs and energy savings. Therefore, urgent action is required to reduce environmental impact without compromising the safety of patients and staff. A wide range of interventions is possible if certain key requirements are met: engaging healthcare professionals as leaders of transformation, developing innovative and health-specific green solutions with significant impact, ensuring the adoption of these solutions, and verifying that they are environmentally sustainable, cost-efficient, and scalable. The ClimAte neutRal INitiatives for GrowiNg heAlTh and care Unmet REquirements (CARING NATURE, CN) project is one of the first Horizon Europe research and innovation programs addressing these issues and developing solutions based on the aforementioned requirements. Its relevance is also evidenced by its mention in the WHO COP29 special report on climate change and health. Building on the CN project's highlights, this workshop aims to address the urgent need for sustainable solutions within the healthcare sector. As this sector continues to grow, its environmental footprint will also increase, making it imperative to explore innovative strategies for reducing carbon emissions and pollution. This session will serve as a platform to bring together the public health community to discuss and develop actionable solutions for implementation across various healthcare settings and to explore how to foster the adoption of these solutions across different regions and healthcare systems. In this scientific session, insights from CN findings will be presented, followed by an open discussion with participants. The first presentation will provide the healthcare sector's responsibility in mitigation actions aimed at reducing GHG emissions, using the CN project as an example. The second presentation will highlight one of the main solutions addressing these challenges: the development of a Knowledge Sharing System as a key tool for healthcare management and education in this field. The third presentation will focus on necessary staff engagement through participatory methods for Communities of Practice to achieve environmentally sustainable healthcare facilities. The final presentation will demonstrate the implementation of the Knowledge Sharing and Decision Support System for healthcare management in the Wellbeing services county of Päijät-Häme in Finland. The entire scientific session will offer an opportunity to share experiences and challenges across different European contexts and analyze how CN solutions could be implemented and adapted.Key messages• The healthcare sector's GHG emissions are set to rise by 2050 without intervention. The CN project offers innovative solutions to reduce emissions while ensuring patient and staff safety.• The CN project highlights the need for sustainable healthcare practices. It emphasizes engaging professionals, developing green solutions, and fostering adoption to mitigate environmental impact.

Why is the problem?China is considered the strongest nation based on its economy.This cherished economy is not the gift of God rather it is possible by altering the God gifted natural resources of it.By doing so, a tremendous pressure is continually being exerted on the environment of Chinese territory.It has already overtaken the other mighty nation -the US with respect to GHG (Green House Gas) emission.Despite serious efforts that have been made to shift the energy mix in favor of non-fossil fuels, as of 2011, China still requires 50% higher energy intensity than the US.China's proportion of global GHG emissions is projected to rise from 17% in 2005 to 26% in 2030, reaching 16.664Gt CO 2 e.The dependency of coal and use in enormous amount is the single dominant cause of the so called Smog pollution in China.

The trends of consumption-based emissions in China have a major impact on global greenhouse gas (GHG) emissions. Previous studies have only focused on China’s energy-related consumption-based emissions of CO2 or specific non-CO2 GHGs without taking overall consumption-based non-CO2 GHG emissions into account. Based on a constructed global non-CO2 GHG emissions database, combined with CO2 emissions data, this paper fills this gap through an examination and analysis of China’s GHG emissions using a global multi-regional input–output (MRIO) model for 2004, 2007 and 2011, and identifies the major factors driving changes in consumption-based emissions through a structural decomposition analysis (SDA). The results show that compared with CO2 emissions, CH4, N2O and F-gases emissions all increased more rapidly. Among consumption-based non-CO2 GHG emissions, investment-based emissions experienced the fastest growth, but the net exports of non-CO2 GHG emissions dropped drastically in recent years. While investment in total final consumption demand is the most influential factor for CO2 emissions, household consumption most significantly affects the growth in consumption-based non-CO2 GHG emissions.

With increasing awareness of agriculture's contribution to global greenhouse gases (GHGs) and China's position as the world's top GHG emitter, there is heightened attention to the embodied emissions in China's food consumption. China's diet has shifted to include more fruit, vegetables, meat and dairy. Not surprisingly, GHG emissions from food consumption have also increased substantially. This analysis links China's food consumption with the emissions of food production industries in China and its trade partners to determine the effects of dietary change on GHGs since 1989. We utilise high‐resolution food production and emissions data to perform a logarithmic mean Divisia index decomposition to attribute changes in GHG emissions to the scale, supply structure, demand structure and efficiency effects resulting from Chinese dietary changes over a 20‐year period. This study finds that while countries supplying food to China contribute little to China's food‐related GHGs, demands for meat and dairy play a much larger role, driving up emissions. The overall scale of increased consumption of all food further propels growth in GHG emissions. Results indicate, however, that while food consumption in China more than doubles between 1989 and 2009 improvements in technological efficiency limit the rate of increase.