Evaluating embodied energy, carbon impact, and predictive precision through machine learning for pavers manufactured with treated recycled construction and demolition waste aggregate.

This investigation assesses the embodied energy and carbon footprint in the manufacture of pavers using varying proportions of recycled Construction and Demolition Waste (CDW). Additionally, Thin Film Composite Polyamide fiber (TFC PA), extracted from end-of-life Reverse Osmosis (RO) membranes, is introduced as an additive to enhance the concrete's strength. Machine learning techniques, namely Artificial Neural Network (ANN), Support Vector Regression (SVR), and Response Surface Methodology (RSM), are employed to predict the mechanical properties of pavers. The study focuses on examining the energy required and embodied carbon in various mix proportions, as well as the mechanical properties-specifically compressive strength and split tensile strength of concrete with different CDW and TFC PA proportions. Findings reveal that the optimal percentage of TFC PA is 3 % for all CDW replacement proportions, resulting in low carbon content both in terms of energy and embodiment and in mechanical behavior. The implementation of ANN and SVR is conducted in MATLAB, while a Design Expert is employed to generate the experimental design for RSM. The RSM regression model demonstrates a robust correlation between variables and observed outcomes, with optimal p-values, R2 values, and f-values. The ANN model successfully captures the variability in the data. Additionally, the findings indicate a consistent superiority of the Support Vector Regression (SVR) model over both Artificial Neural Network (ANN) and Response Surface Model (RSM) models when considering diverse performance metrics such as residuals and correlation coefficients.

Dynamic analysis of carbon emissions from construction and demolition activities in Japan: Revealed by high-resolution 4D-GIS modeling.

To meet the 2050 decarbonization target of the global buildings and construction sector, more attention is needed to reduce carbon emissions from construction and demolition. However, current national carbon accounting studies for these activities remain limited in spatial granularity and localized applicability. This study developed a bottom-up spatiotemporal database of carbon emissions from building construction and demolition in Japan via integrating a geographic information system-based building stock model, statistical data, and survey information. Focusing on municipal-level emissions, the Logarithmic Mean Divisia Index approach was used to decompose spatiotemporal variations and identify the contributing factors. Results indicate that carbon emissions from Japan's construction and demolition activities fell by more than 50% between 2005 and 2020, largely due to declining new/demolished-to-stock ratio, suggesting a transition to a stock-based society. Central cities' reliance on carbon-intensive buildings positively contributed to spatial variations in their construction emissions, underscoring the importance of sustainable materials and timber designs. Differences between prefectures in demolition emission intensity highlighted the strategic placement of recycling facilities in key regions to curb transportation-related emissions. Overall, these findings provided data reference for local governments to devise tailored policies for managing construction and demolition emissions.

Tele-connection of embodied carbon emissions from industries in China's trade: A complex network analysis.

Regions can meet their development demands through trade, with the attendant environmental costs being shifted to other regions, and carbon emissions emitted from different industries could be transferred over long distances through the increasingly diversified trade network. However, it remains unclear how regional trade leads to the tele-connection and transfer of embodied carbon emissions form industries, and what is the structure and characteristics of the transfer. Thus, multiregional input‒output models and complex network analysis are employed to reveal the tele-connection of carbon emissions from industries in China. The results show that embodied carbon emissions from trade increased by 869.47 million tons during in five years, with North China being the largest outflow area, while the coastal regions being the inflow areas. Moreover, the secondary industry is the highest source of embodied carbon emissions, accounting for 96.68 % of the volume, and the transfer of carbon emissions mainly occurs in North and East China. In carbon emissions networks, North China holds a controlling position, as analysed by degree and strength. The first 23.3%-30% of nodes carry about 62.6%-72.4% of the entire carbon emissions flow, and the network conforms to scale-free features. Centrality further reveals that northern and coastal areas occupy core positions, with interregional carbon flows dominating the critical pathways in the network. The number of clusters evolved from three to four communities during 2012-2017 in the network, demonstrating that the carbon flow network is developing towards multipolarity and modularity. This study underscores the urgency of mitigating carbon emissions in industrial trade by identifying key nodes and cluster structures in emission networks.

Digital inclusive finance and consumption-based embodied carbon emissions: A dual perspective of consumption and industry upgrading.

Promoting the development of financial instruments can influence carbon emission reduction in the context of the carbon peaking and carbon neutrality goals. There are currently no theoretical mechanisms to explain whether and how digital inclusive finance, as a new type of financial service, influences residential consumption-based embodied carbon emissions. This study employs the mediation model, moderation model, and moderated mediation model to empirically evaluate the influence mechanism of digital inclusive finance on consumption-based embodied carbon emissions per capita in China from 2011 to 2019. The findings demonstrate that the development of digital inclusive finance increases residents' consumption-based embodied carbon emissions by upgrading consumption level and consumption structure, but that upgrading industrial structure does indeed have a significantly negative moderating effect in implications paths, causing consumption-based embodied carbon emissions to shift from positive to negative. This study, by focusing on the advancement of digital inclusive finance, offers policymakers suggestions for reducing consumption-based embodied carbon emissions from the standpoints of consumption upgrading and industrial structure upgrading, respectively.

The carbon emissions related to the land-use changes from 2000 to 2015 in Shenzhen, China: Implication for exploring low-carbon development in megacities.

Megacities exploit enormous amounts of lands from outside of the city boundary. However, there is a large knowledge gap in the impact of socioeconomic activities associated land-use changes on carbon emissions of megacities during the urbanization. In the current work, we combined the material-flow analysis, environmental extended input-output model, and land matrix data to construct a hybrid network framework. Such a framework was used to estimate the carbon emissions driving from trade between sectors and associated land use changes during 2000-2015 in Shenzhen, China. Results indicated that the total carbon emissions of Shenzhen had a growth rate of 262.7% from 2000 to 2010 and a declining rate of 17.6% from 2010 to 2015. This pattern is associated with large declining rates in the overall energy and carbon intensities by 53.8% and 63.2% during the period of 2000-2015. Meanwhile, embodied carbon emissions of Shenzhen kept rising by approximately twofold, accompanied by the increasing trends in the land-use related carbon emissions both inside and outside of city boundary. The land uses per unit GDP showed a dramatical decline by 85.7% and with a large contribution of the transportation and industrial land, and this caused a gradual increase in overall land-use related emissions with average growth rate of 7.1%. In addition, the land-use change related carbon emissions of the transportation and industrial land had a cumulative growth of 85%. As for the embodied land-use related carbon emissions, the dominated contributor was the Agriculture sector which drove an average of 0.13 MtC yr-1 emissions via importing agricultural products from outside of Shenzhen. This study provides a scientific foundation for corporately mitigate carbon emissions between megacities and their surrounding regions.

Export trade, embodied carbon emissions, and environmental pollution: An empirical analysis of China's high- and new-technology industries.

China's export trade has been expanding steadily in recent years, significantly increasing resource consumption and environmental pollution. High- and new-technology industries are essential for achieving sustainable economic development and improving environmental quality. This study employs a multi-regional input-output model to estimate the economic benefits and environmental costs of export trade in high- and new-technology industries. Then, it analyzes the impact of economic benefits and technological levels on environmental pollution using the Stochastic Impacts by Regression on Population, Affluence, and Technology model. An input-output multi-objective linear programming model and a non-dominated sorting genetic algorithm II are adopted to combine economic development with environmental pollution and determine the optimal path for export trade. The results show that technological progress in China's high- and new-technology industries is conducive to reducing embodied carbon emissions in developed countries while increasing emissions in developing countries. Moreover, a nonlinear three-stage accompanying relationship exists between the economic benefits and environmental costs of high- and new-technology exports; this is because exports with low economic benefits generate fewer carbon emissions whereas exports with high economic benefits generate significant carbon emissions. An increase in exports with ultra-high economic benefits will generate excessive embodied carbon emissions that hinder coordinated economic-environmental development. Lastly, technological progress in the electrical and optical equipment sector can effectively promote pollution reduction; thus, it should be further developed to improve the comprehensive benefits of exports.

The mutual benefits from Sino-Africa trade: Evidence on emission transfer along the global supply chain.

The carbon-emission transfer between two representative developing economies - China and Africa - behind the international trade has aroused quite a few controversies, which have not been fully estimated and understood yet. In this paper, the Multiregional Input-Output (MRIO) method is applied to the participants of Forum on China-Africa Cooperation (FOCAC) from the global perspective to reveal the roles both China and Africa have played in the global supply chain as either the original emitter or the final consumer, and to depict the evolution pattern of carbon transfer via Sino-Africa trade from the year 2000-2015. The findings are as follows: 1) China has played the role of net exporter of embodied carbon-emission in Sino-Africa trade, for the amount of emitted carbon China had born yet resulted by consumption in Africa well surpassed that vice versa. 2) Compared to the carbon-emission flows embodied in EU-Africa and US-Africa trades, China has shouldered more carbon-emission derived from Africa's consumption. 3) The sectoral contribution and intensities of embodied carbon-emission correspond to the trading pattern between China and Africa, which stems from the two parties' comparative advantages and economic complementarity. 4) The intensities of embodied carbon-emission on both sides are declining towards a rosy prospect, which indicates an improving carbon-emission efficiency of both economies. From a global perspective, both China and Africa play a positive part in carbon-emission reduction. The results in this study can facilitate low-carbon and high-efficiency trading link between the two economies.

Embodied carbon dioxide flow in international trade: A comparative analysis based on China and Japan.

Carbon dioxide embodied flow in international trade has become an important factor in defining global carbon emission responsibility and climate policy. We conducted an empirical analysis for China and Japan for the years 2000-2014, using a multi-region input-output model and considering the rest of the world as a comparison group. We compared the two countries' direct and complete carbon dioxide emissions intensity and bilateral economic activities such as imports and exports, production and consumption to analyze the difference between China and Japan. The results showed that the intensities of carbon emissions in all sectors of China were higher than that in Japan and that China's annual production-based emissions were greater than consumption-based emissions, the opposite of these relationships in Japan. China was a typical net carbon export country, and carbon embodied in its imports and exports continued to increase throughout the study period. In contrast, Japan's volume and growth rate of embodied carbon emissions were far less than China's and Japan was a typical net carbon import country. Finally, the conclusions of this study support recommendations for the formulation of international carbon emission responsibility allocation, domestic abatement policy as well as China's trade policy.

Embodied carbon mitigation and reduction in the built environment - What does the evidence say?

Of all industrial sectors, the built environment puts the most pressure on the natural environment, and in spite of significant efforts the International Energy Agency suggests that buildings-related emissions are on track to double by 2050. Whilst operational energy efficiency continues to receive significant attention by researchers, a less well-researched area is the assessment of embodied carbon in the built environment in order to understand where the greatest opportunities for its mitigation and reduction lie. This article approaches the body of academic knowledge on strategies to tackle embodied carbon (EC) and uses a systematic review of the available evidence to answer the following research question: how should we mitigate and reduce EC in the built environment? 102 journal articles have been reviewed systematically in the fields of embodied carbon mitigation and reduction, and life cycle assessment. In total, 17 mitigation strategies have been identified from within the existing literature which have been discussed through a meta-analysis on available data. Results reveal that no single mitigation strategy alone seems able to tackle the problem; rather, a pluralistic approach is necessary. The use of materials with lower EC, better design, an increased reuse of EC-intensive materials, and stronger policy drivers all emerged as key elements for a quicker transition to a low carbon built environment. The meta-analysis on 77 LCAs also shows an extremely incomplete and short-sighted approach to life cycle studies. Most studies only assess the manufacturing stages, often completely overlooking impacts occurring during the occupancy stage and at the end of life of the building. The LCA research community have the responsibility to address such shortcomings and work towards more complete and meaningful assessments.

Effect of wheat straw ash as cementitious material on the mechanical characteristics and embodied carbon of concrete reinforced with coir fiber.

The use of supplementary cementitious materials has been widely accepted due to increasing global carbon emissions resulting from demand and the consequent production of Portland cement. Moreover, researchers are also working on complementing the strength deficiencies of concrete; fiber reinforcement is one of those techniques. This study aims to assess the influence of recycling wheat straw ash (WSA) as cement replacement material and coir/coconut fibers (CF) as reinforcement ingredients together on the mechanical properties, permeability and embodied carbon of concrete. A total of 255 concrete samples were prepared with 1:1.5:3 mix proportions at 0.52 water-cement ratio and these all-concrete specimens were cured for 28 days. It was revealed that the addition of 10 % WSA and 2 % CF in concrete were recorded the compressive, splitting tensile and flexural strengths by 33 MPa, 3.55 MPa and 5.16 MPa which is greater than control mix concrete at 28 days respectively. Moreover, it was also observed that the permeability of concrete incorporating 4 % of coir fiber and 20 % of WSA was reduced by 63.40 % than that of the control mix after 28 days which can prevent the propagation of major and minor cracks. In addition, the embodied carbon of concrete is getting reduced when the replacement level of cement with WSA along with CF increases in concrete. Furthermore, based on the results obtained, the optimum amount of WSA was suggested to be 10 % and that of coir fiber reinforcement was suggested to be 2 % for improved results.

A sustainable novel approach of recycling end-of-life reverse osmosis (RO) membrane as additives in concrete and mathematical model with response surface methodology (RSM).

This study investigates a novel method of recycling end-of-life reverse osmosis (RO) membranes to enhance the mechanical properties of concrete. Reverse osmosis (RO) is a widely used technology for water purification and desalination, but it has various environmental problems that require attention. RO membranes have a short service life, resulting in the generation of end-of-life (E-o-L) RO membrane trash in thousands of tons each year, which is typically disposed of in landfills, polluting land resources. The RO membrane primarily comprises a thin-film composite of polyamide (TFC PA) as a filter medium. The material properties of TFC PA are studied and added to the concrete as an additive in the cement volume at 1 to 20%. The optimum mix is identified at 3.4% of TFC PA, and the mechanical properties are nearly 17% greater than the control mix. SEM/EDX shows a higher bonding between TFC PA and the concrete, and TGA results exhibit the mass loss increasing with the increase in TFC PA. MIP analysis shows that the volume of cumulative pores and intruded volume is increased with increasing TFC PA. A sustainability study was carried out to evaluate the energy consumed and embodied CO2 in the mixes and compared them with the control mix. The mathematical model for compressive strength at 7 days, 14 days, and 28 days is done using response surface methodology (RSM) with the independent variables of TFC PA, slump, and superplasticizer. The adopted regression illustrates a significant relationship between the response and variables, proving a higher R2 for all the models and optimal p-values for the responses. They show that TFC PA influences the enhancement of properties of concrete. The residual also proves to be very minimal in the model.

A compiled dataset of ready-mix concrete Environmental Product Declarations for life cycle assessment.

The carbon footprint of a concrete structure is directly affected by the selected concrete mixture proportions. To better understand the influence of different concrete mixtures, data was collected from Environmental Product Declarations (EPDs). Data from 39,213 U.S.A. ready-mix concrete EPDs was obtained from public repositories provided by the American Society for Testing and Materials and the National Ready Mixed Concrete Association. The EPDs in .pdf format were analyzed using a custom Python script to extract useful information for building designers, sustainability practitioners, and researchers including: life cycle assessment (LCA) midpoints (Global Warming Potential, Ozone Depletion Potential, Acidification Potential, Photochemical Ozone Creation Potential, Abiotic Depletion, Total Waste Disposed, and Consumption of Freshwater), concrete strength classes, declared unit, concrete curing time, production components, concrete manufacturers' company and plant locations, and additional LCA information. Both the dataset and an example of the Python script used to extract the information from the EPDs are provided. This dataset enables users to quickly assess the environmental impacts (including the Global Warming Potential) of different concrete mixtures without the need for extensive data collection and analysis. In summary, this dataset provides environmental information about concrete mixtures to aid civil engineering and architectural researchers, sustainability consultants, building engineering practitioners, and environmental policymakers to make sustainability-informed decisions when specifying concrete in the U.S.A.

Decarbonization potentials of the embodied energy use and operational process in buildings: A review from the life-cycle perspective.

Accounting for one third of global energy-related carbon emissions, the construction and operation of buildings are crucial for mitigating climate change. Decarbonization potentials of embodied and operational energy use in buildings are worth exploring from a life-cycle perspective. This paper focuses on the individual building level and collects the latest cases, to offer a comprehensive and timely understanding of the assessment and reduction of building life cycle carbon emissions (LCCEs). As for the collected cases, the operational process accounts for the largest share of building LCCEs, averaging 67%, followed by the production and construction phase, averaging 31%. Carbon emissions from the demolition process are relatively low, averaging 2%. The most commonly used method for assessing LCCEs is process-based, combining the activity level and carbon emission factors. Advanced technologies such as building information modelling and building performance simulation have been employed in recent years to assess embodied and operational carbon emissions effectively. Different approaches are proposed for the decarbonization of each stage in the building life cycle. In the production stage, the effective approaches could be optimizing the building structure, improving the material performance, and using bio-based materials, etc. Prefabrication technology is helpful to decarbonize the construction process. Energy conservation and electrification, renewable energy integration, and smart energy management can effectively reduce the building's operational carbon emissions. Beyond the life cycle, recycling waste materials is proven to have great environmental benefits. Further studies are suggested to trade off the embodied and operational carbon, to fully explore building life-cycle decarbonization potentials.

Reassessing the embodied carbon emissions in China's foreign trade: a new perspective from the export routes based on the global value chain.

A new route perspective measure based on the global value chain (GVC) distinguishes the embodied emission transfer destinations while concurrently considering the transfer process and GVC embedding position. This study applies this measure to reassess the characteristics of China's foreign trade embodied emissions and their impacts on global emissions. The results show that: (1) China's domestic embodied emission exports are mainly concentrated in manufacturing and dominated by final goods exports and simple GVC routes. China primarily imports foreign emissions via simple GVC routes. (2) The embodied emission intensity of China's exports is much higher than that of its imports, and China's expansion in imports indirectly promoted global emission reduction. (3) China's foreign trade increases global emissions with a waning trend, while GVC-related trade reduces global emissions. Additionally, it is feasible to reduce global emissions by adjusting China's bilateral trade structures with different countries. We conclude that China's GVC-related trade has increased, but exports through complex GVC tend to be the resource-input type. We emphasize that China needs to actively participate in globalization and upgrade its GVC to step off the low-end locking predicament in global production and cope with the multiple pressures of global and domestic emission reduction and stable development.

Assessment of building materials in the construction sector: A case study using life cycle assessment approach to achieve the circular economy.

The construction sector plays a significant role in contributing to greenhouse gas (GHG) emissions, necessitating effective and practical solutions. This study addresses the underutilization of Life Cycle Assessment (LCA) in the construction sector and demonstrates its benefits as a decision-making tool for mitigating embodied carbon. The research focuses on a G+2 building in Dubai, UAE, conducting LCA during the construction phases to assess embodied carbon levels. Results indicate that the careful selection of construction materials and involvement of LCA at the early stages of construction resulted in a 26 % reduction in the building's embodied carbon. The study recognizes the limitations of LCA but emphasizes its value and recommends future research to enhance its coverage of sustainability aspects. The findings highlight the construction sector's potential to overcome anthropogenic challenges through green solutions. Policymakers' support is crucial for implementing strategies that reduce the construction industry's carbon footprint and embrace a circular economy. The study contributes to the literature by bridging the gap in understanding the application of LCA in construction decision-making. It emphasizes the importance of transitioning to sustainable practices and circularity in the construction sector. By using LCA as a tool, construction professionals can make informed choices to reduce embodied carbon. This study underscores the urgency for adopting greener practices in the construction sector, leading to a more sustainable and low-carbon future.

Cluster characteristics of embodied carbon emissions in the international trade of metals: a sectoral-regional modeling perspective.

To be able to formulate any plausible strategies for sustainability, it is critical to establish a clear understanding of the international metals trade system complexity and the consequences in emergent embodied carbon emissions (ECE). For this purpose, we proposed a two-layer framework based on the multi-regional input-output model for calculating ECE: the intermediate production and final consumption trade layers. The proposed framework model combines the construction of a clustering index system and conducting cluster analysis from both the regional and sectoral dimensions. It is shown that developed regions transfer carbon emissions to developing regions via metals trading. This happens especially in the intermediate production stage at a level of 1.35 times higher than the final consumption stage. Furthermore, the metal sector suffers the most from carbon transfers from manufacturing, with the most carbon emissions transferred to mining. Moreover, considering environmental and technological factors to cluster regions and sectors into four and three clusters. China and Russia are in a cluster under greater pressure to reduce emissions as compared to other nations. Also, the construction and manufacturing form a cluster that their reduction of carbon emissions will effectively reduce the ECE of the metal sector. As a result, policy implications for reducing carbon emissions are investigated for each cluster in the international trade of metals contributing to the ultimate goal of global sustainable development.

Spatio-temporal changes and root-cause identification for embodied carbon emissions based on production and consumption in China's Yangtze River Economic Belt.

The Yangtze River Economic Belt (YEB) is at the centre of China's economy and development. Its regional carbon emissions account for about 36.9% of the country's total carbon emissions, and thus, there is an urgent need to sustain the development of a low-carbon economy. However, the complex patterns of embodied carbon flows arising from multi-scale trade in such a megaregion are often ignored in carbon environmental governance. This study incorporates a megaregion into an environmentally extended multi-regional input-output (EEMRIO) framework and identifies the drivers of production and consumption-based carbon emissions using four measures through structural decomposition analysis (SDA). The results show that (1) the YEB strengthens inter-provincial trade links while reducing international trade links; (2) there is obvious carbon transfer in multi-scale trade in the YEB, with a corresponding transfer of responsibility for carbon reduction occurring; and (3) consumption volume and carbon intensity are the main drivers and inhibitors of the increasing carbon emissions, respectively, and the optimisation of production structure and consumption structure are effective ways to control production-based carbon emissions (PBEs) and consumption-based carbon emissions (CBEs), respectively. This study extends the research scale of "national-provincial-city" to a megaregion. Studies based on multiple trade scales would provide additional insights to understand the carbon reduction responsibilities of megaregions and help achieve coordinated regional carbon reductions.

Differences in carbon emissions between the digital economy sectors in China and the USA.

In an era of rapid development of digital technologies and dramatic global climate change, digital economy is crucial to achieving the 'carbon peak' and 'carbon neutral' goals. However, less research has been done in the area of indirect carbon emissions in the digital economy sector. Therefore, this study uses an input-output model to calculate the embodied carbon emissions of the ICT (information and communication technology) industry in China and the USA in 2005, 2010 and 2016 from the production and consumption sides. Moreover, a comparative analysis is conducted in terms of the driving factors of carbon emissions and the relationship between emissions and economic benefits in the two countries. The results reveal that emissions are larger on the production side in the USA and on the consumption side in China. For both countries, electricity is the largest upstream sector in terms of emissions. ICT in the USA causes sectoral emissions mainly in manufacturing and services. While China mainly causes sectoral emissions in manufacturing. The US ICT sector is more economically efficient for the same emissions. Regarding drivers, the primary driver of the fall in emissions is a reduction in emission intensity. The increase in emissions driven by final demand is greater in China than in the USA. Finally, the results of the two countries are extended to other developed countries and emerging economies, providing recommendations for reducing carbon emissions in the ICT sector.

The fairness of shared responsibility for embodied carbon emission: a case study of the Yellow River Basin, China.

Under the dual constraints of China's carbon peaking and carbon neutrality goals, as well as ecological protection and high-quality development of the Yellow River Basin, clarifying the embodied carbon emissions and responsibility sharing of inter-provincial trade is crucial to the carbon reduction strategy of the Yellow River Basin. This paper uses the MRIO (multi-regional input-output) model to measure the production-side and consumption-side responsibility sharing of nine provinces in the Yellow River Basin in 2012 and 2017, revealing the amount and direction of the embodied carbon transfer between provinces, and finally introduces the share of provincial value added as the responsibility sharing factor to compare and analyze the differences between the three responsibility sharing methods. The results show the following: (1) The embodied carbon emissions on the production side in most provinces of the Yellow River Basin were larger than that on the consumption side, with the most significant differences in Shanxi, Inner Mongolia, and Shandong, among which local demand carbon emissions and intermediate product transfer out of carbon emissions were the main causes of production-side carbon emissions. (2) In general, all provinces except Shaanxi were net carbon transfer-in regions, and the embodied carbon was mainly transferred to Beijing, Jiangsu, Guangdong, Zhejiang, and Hebei. (3) Shared responsibility for carbon emissions was jointly determined by the volume of embodied carbon trade and the ability to obtain value added, which lay between production and consumption side responsibility shares. (4) The Yellow River Basin had a large responsibility-sharing factor and embodied carbon trade, and thus needs to take more responsibility for emission reduction. This study is expected to provide scientific support for the strategy of differentiated emission reduction in the Yellow River Basin and enrich the regional carbon accounting methods.

Shared responsibility of carbon emission for international trade based on carbon emission embodied between developing and developed countries.

Traditional Production-Based Accounting (PBA) principle does not consider the embodied carbon emissions in export and import trade. A multiregional input-output (MRIO) model is constructed to estimate the embodied carbon dioxide emissions of 41 countries and regions worldwide, based on the PBA and shared responsibility approach in this paper. The results indicate that the embodied carbon emissions in 2018 in China's export trade were 1326 million tons higher than that of import trade. China, India, and the USA have a different carbon coefficient in the 35 sectors, but electricity, gas, and water supply sectors are the largest coefficient for them. A reduction in carbon emission coefficient would contribute to a decrease in imports and exports. Through the empirical analysis of the embodied carbon emissions in China's import and export trade, it can be seen that China is a major producer of carbon emissions, not a consumer country, and has taken more carbon emissions responsibility for the world. The developed countries should take more shared carbon emission responsibility than the PBA. And it is more reasonable and impartial to assign developed and developing countries carbon emissions responsibility in the light of the shared responsibility method.