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To mitigate greenhouse gas (GHG) emissions from the wastewater treatment industry, it is crucial to explore GHG emission patterns and propose useful measures. In this study, we use the Kaya model and LMDI decomposition method to analyze the changes in GHG emissions from urban domestic wastewater treatment at the provincial level and further explore the distribution characteristics and driving factors of urban domestic wastewater treatment GHG emissions across various years and regions. The results indicate the following: (1) In the temporal dimension, urban domestic wastewater treatment GHG emissions are increasing, from 21.0 MtCO2 in 2011 to 27.1 MtCO2 in 2020, with an average annual growth rate of 2.88%. The spatial distribution is high in the southeast and low in the northwest. There is variability in the spatial evolution trend of GHG emissions by province, with the growth rate becoming slower or even negative in Jiangsu, Zhejiang, and North China, while the average annual growth rate exceeds 25% in Inner Mongolia and Xinjiang. (2) According to the decomposition results of driving factors, economic scale is the dominant positive driver, and the positive contributions of TI and the population effect are limited. The sludge disposal structure is the main negative driver, and the EEI and technology have restricted negative contributions. (3) Based on the decomposition results, for major coastal GHG emitters, such as Guangdong and Shandong, it is necessary to invest capital and technology to continuously upgrade the wastewater treatment process and reduce non-CO2 emissions. Along with adopting circular economy schemes, local governments in the northwestern region should transform the traditional sludge disposal structure and optimize the power supply structure to increase carbon offset and reduce CO2 emissions. The findings suggest a low-carbon transformation path to support the industry's dual carbon goals. [ABSTRACT FROM AUTHOR]

The building sector, which accounts for over 20% of China's total energy-related carbon emissions, has great potential to reduce emissions and is critical to achieving China's emissions peak and carbon neutrality targets. However, the lack of data on operational carbon emissions and end-use carbon emissions in the building sector at the city level has become a major barrier to the development of building energy conservation policies and carbon peaking action plans. This study uses a combination of "top-down" and "bottom-up" methods to account for the operational carbon emissions of buildings in 321 cities in China from 2015 to 2020. The energy consumption in buildings is further broken down into six end uses: central heating, distributed heating, cooking and water heating (C&W), lighting, cooling, appliances and others (A&O). The dataset can serve as a reference to support city-level policies on peak building emissions and is of great value for the improvement of the carbon emissions statistical accounting system. [ABSTRACT FROM AUTHOR]

The construction industry plays a crucial role in achieving carbon neutrality by reducing energy consumption. However, Building energy consumption (BEC) in China is increasing concomitantly with the rapid increase in urbanization. This study utilizes nighttime light data to construct a nighttime light index for urbanization, and empirically studies the impacts of urbanization on BEC intensity. The results show that there is a statistically significant positive correlation between BEC intensity and urbanization level on a nationwide scale, while an inverted-U relationship exists in Eastern developed regions, suggesting that an increasing BEC intensity is not an inevitable result of urbanization. Urbanization in the compact city mode inhibits BEC intensity to some extent, while urbanization in the urban sprawl mode often develops at the expense of increasing BEC intensity. The acceleration of the regional coordinated development and the adoption of the compact city mode are suggested to achieve energy-saving and emission-reduction targets. [ABSTRACT FROM AUTHOR]

City size expansion in China creates substantial economic circulation, which impacts CO2 emissions. Since CO2 production primarily comes from human activities, CO2 emissions are mainly in cities. To achieve China's carbon neutrality and provide specific implementation guidance for future carbon-reduction policies, it is worth assessing China's pressure on carbon reduction in the urban aspect. Highly developed social productivity and a market economy lead to a dramatic increase in the interconnection between cities, and the spatial distribution of CO2 emissions emerges in a spatial association. Therefore, it is of great significance to investigate the interaction of CO2 emissions with spatial effects. Taking the Yangtze River Delta urban agglomeration (YRDUA) as the research target area, this paper utilizes city-size indices to construct spatial-association networks of CO2 emissions for the first time. It employs social network analysis to explore the structures of whole networks, clusters, and city nodes. The main results show that: (1) the spatial associations of CO2 emissions in the YRDUA's cities have become tighter over time. (2) The networks of CO2 emissions in the YRDUA's cities have noticeable spatial-spillover effects, and the interaction of CO2 emissions between cities is dominant. (3) Nanjing is the paramount "bridge" node in the networks. (4) Nanjing, Hangzhou, Wuxi, Shanghai, Changzhou, Suzhou, Nantong, and Hefei will be the decisive cities for efficient CO2 emission control in the future. Overall, this paper reveals the role of carbon reduction in the YRDUA's cities and proposes suggestions for establishing a transboundary energy-saving mechanism to improve the efficiency of energy conservation and emission reduction. [ABSTRACT FROM AUTHOR]

As the energy demand of public building (PB) in China continues to increase, it is meaningful for forecasting the future trend of carbon emissions (CE) of PB. This study analyzes the drivers of CE that affect the operational stage of PB in China by the Generalized Divisia Index Method (GDIM), which considers the effect of the output value and structural transformation of the tertiary industry and makes a scenario prediction of the future carbon-neutral trajectory of CE in PB under the Shared Socioeconomic Pathway (SSP). The results show that from 2010 to 2020, the added value of the tertiary industry (AVTI) is the strongest positive driver of CE from PB (31.912% of the total contribution), which correspond to a cumulative contribution of 212.3 million tons (MtCO 2) in 11 years. Regulating the CE per unit of the AVTI is the key indicator in reducing CE from PB, with a cumulative reduction of 130.1 MtCO 2. The results of the five scenarios under the SSP framework differ significantly, with SSP1 peaking first in 2026 at 884.5 MtCO 2 (876.2–893.9 MtCO 2) and SSP5 peaking latest in 2049 at 1372.3 MtCO 2 (1362-1389.7 MtCO 2). SSP1 yielded the smallest projection in 2060 with 189.8 MtCO 2 (185.4–194.3 MtCO 2). The findings could help public buildings to implement carbon reduction and provide more scientific and rational decision support for possible paths to achieve carbon neutrality in China. • Projection of carbon emission changes in China's public building operation phase to 2060. • The GDIM which considers the added value of the tertiary industry and industrial transformation factors are employed. • Added value of tertiary industry is essential to the change of carbon emissions. • Carbon emissions of public buildings peak first in 2026 and are lowest in 2060 under the SSP1 scenario. [ABSTRACT FROM AUTHOR]

The decarbonization of China's central heating (CH) is important for reaching China's carbon peak and carbon neutrality goal. However, unclear CO 2 emissions from CH of each city and their disparity hinder the formulation of targeted decarbonization strategies. To solve these issues, this study quantifies the CO 2 emissions from CH in 137 cities during the period of 2006–2019 and introduces the Kaya identity and Theil index to investigate the disparity in the per capita CO 2 emissions from CH. The results indicate that 1) China's CH CO 2 emissions increased to 435.53 MtCO 2 in 2019. Residential and public and commercial (P&C) buildings accounted for 74.18% and 25.82%, respectively. 2) The cities with the largest CH CO 2 emissions of all (22.58 MtCO2), residential (16.33 MtCO 2), and P&C buildings (6.86 MtCO 2) were Harbin, Shenyang and Harbin, respectively. 3) The Theil index for all buildings decreased to 0.44 in 2019, and P&C buildings had the largest disparity. 4) The central heating penetration rate was the major positive contributor to the disparity of residential and P&C buildings, contributing more than 40%. In summary, at the city level, this study offers a comprehensive investigation of the CO 2 emissions from CH and benefits the formulation of specific decarbonization strategies. [Display omitted] • The CO 2 emissions from China's central heating (CH) are quantified at the city level. • The Theil index was employed to determine the disparity of per capita CO 2 emissions from CH. • Residential buildings have a larger disparity than public and commercial (P&C) buildings. • The CH penetration rate was the major positive contributor to the disparity. • Eliminating the disparity can reduce CO 2 emissions of China's CH by 6.92% -77.74%. [ABSTRACT FROM AUTHOR]

Equitable and effective allocation of provincial carbon allowances is the key to achieving carbon peaking and carbon neutrality targets and addressing the prominent issue of resource and environmental constraints, while reasonable coupling of equity and efficiency is its prerequisite. The study first assessed the effectiveness of the mainstream allocation methods when applied to the building sector. Then, Monte Carlo simulation is used to properly couple the principles of equity and efficiency in the process of carbon allowance allocation in the building sector, and on this basis, a novel Allocation method of Regional Carbon Allowance in Building sector (ARCAB) is constructed to provide an inter-provincial allocation scheme of building carbon emission allowances in 2030 for China. The results show that the mainstream allocation methods are not applicable to the building sector, and their allocation results often appear the phenomenon of "low-hanging fruit" or "high-hanging fruit". In addition, the coupling degree of equity-efficiency is 12% in China's 2030 allocation scheme, indicating that provincial governments should formulate more stringent carbon reduction policies to achieve this goal. The proposed ARCAB and our findings can assist decision-makers to formulate reasonable carbon allowances and differentiated emission-reduction strategies and will be of national and global significance. • Propose the criteria to judge the effectiveness of building carbon allowances. • Mainstream carbon allowance allocation methods do not apply to the building sector. • Propose an Allocation method of Regional Carbon Allowance in Building sector (ARCAB). • Focus on carbon reduction in commercial buildings in China. [ABSTRACT FROM AUTHOR]

The CO 2 emission mitigation of the commercial and public building sector (P&C) is critical for achieving China's carbon peak and carbon neutrality. Analyzing changes in CO 2 emissions and their driving factors from temporal and spatial perspective provides insights for developing equitable and effective decarbonization strategies. This study investigated the change in temporal trend and spatial distribution of CO 2 emissions of China's P&C during period of 2005–2018 according to the Kaya identify and Gravity Center model. Meanwhile, combined with the Logarithmic Mean Divisia Index, this study proposed a decomposed method to identify the driving factor of the movement of the gravity center. The results showed that: 1) in the temporal dimension, China's P&C has still not achieved its CO 2 emissions peak, arriving 820.68 MtCO 2. The most positive and negative driving factors were per capita add value of tertiary industry and energy efficiency, respectively; 2) in the spatial dimension, during the 13th Five Year Plan period, the gravity center moved southwestward, and the most positive and negative driving factors were energy consumption unit area and energy efficiency, respectively; Besides, to accelerate the decarbonization of China's P&C, this study reviewed the main decarbonization strategies, divided them into six categories and provided policy implications. In summary, this study provides a completed assessment on CO 2 emission changes of China's P&C, facilitating policy-makers to develop more reasonable implementation plans for emission mitigation. • Temporal trend of the CO 2 emission of China's public and commercial buildings (P&C). • Introducing Gravity center model to quantify the spatial distribution of the CO 2 emissions. • Decomposing the movement of the gravity center to five driving factors. • China's P&C has still not achieved its CO2 emissions peak, arriving at 820.68 MtCO 2. • The gravity center moved southwestward during the period of 2015–2018. [ABSTRACT FROM AUTHOR]

• Modeling the carbon emissions of China's building sector up to 2060. • A multi-layer quantification model covering climate area, building type, and end-use service. • Use building stock dynamic to quantify technique metabolism within building. • Under different scenarios, China's building carbon emissions can reduce by 16%−65%. • The key factors and strategies for future China's building emissions are discussed. Mitigating carbon emissions of China's building sector can significantly contribute toward realizing China's climate goals of achieving carbon peak and carbon neutrality. To understand the carbon emission trend and tap the potential of emission mitigation, this study developed an innovative carbon emissions simulation model that considers climate area, building type and end-use service, and quantifies technique renovation by building metabolism. The results of this study represent China's building sector need to adopt stronger strategies to realize the carbon peak goal. To further conduct deep decarbonization and achieve carbon neutrality, the collective efforts of overall society will lead to the achievement of 64.51% carbon emission mitigation in 2060, decarbonization of electricity generation (47.85%), building stock regulation (M9: 14.24%, 0.14 BtCO 2), and residential green behavior guidance (M10: 13.68%, 0.13 BtCO 2) contribute the top three carbon abatement. Moreover, our results indicate that carbon capture, utilization, and storage techniques must be employed to realize the "last mile" of China building neutrality. Overall, this study provided a valuable reference and emission quantification tool for setting specific carbon emission mitigation goals. [ABSTRACT FROM AUTHOR]

• Dynamic scenario analysis illustrated the stepwise decarbonization potential of building operations. • Annual carbon abatement intensities in China and U.S. in 2001–2018 were 9.8 and 17.7 kgCO 2 /m2. • China will hit CO 2 peak in 2039 at 1365 Mt, while carbon lock-in of the U.S. will stabilize at 664 Mt. • Electricity decarbonization (on-site & off-site) is essential for China and the U.S. to go carbon neutral. • Improving energy efficiency is the best practical way to break the operational carbon lock-in. Building operations are the last steps to achieve global carbon neutrality, especially commercial building operations with high emission abatement potential. Taking China and the United States (U.S.) as cases, this study is the first to illustrate a stepwise decarbonization potential to carbon neutrality in regard to global commercial building operations. The results indicate that the historical annual carbon abatement intensity in China's commercial building operations in 2001–2018 was 9.8 kg of carbon dioxide per square meter (kgCO 2 /m2) or 59.9 kgCO 2 /person, while the annual carbon abatement intensity in the U.S. during the same time was 17.7 kgCO 2 /m2 or 353.7 kgCO 2 /person. In the moderate decarbonization scenario, China's commercial building operations will reach the carbon peak at 1365 (± 255) mega-tons of carbon dioxide (MtCO 2) in 2039 (± 5), while the carbon lock-in status in the U.S. will stabilize at 664 (± 155) MtCO 2 after 2030. To further conduct deep decarbonization and realize carbon neutrality, strategies of building-integrated power generation, building electricity decarbonization, and building energy efficiency can achieve 34.3%, 29.7%, and 22.5% of carbon abatement in China and 31.0%, 45.4%, and 10.2% of carbon abatement in the U.S., respectively, by 2060. Moreover, the current mode of improving the energy efficiency level of commercial building operations was reviewed to seek the best practical way to decarbonize operations. Overall, this study provides a reference of a stepwise data analysis for decarbonization potential on commercial building operations across different emitters. [Display omitted]. Graphical abstract. (a) Decarbonization potential and the steps to carbon neutrality of commercial building operations in China and the U.S.; (b) Technical benchmarks of carbon peak status in China's commercial building operations; (c) Technical benchmarks of carbon lock- in the U.S.'s commercial building operations. [ABSTRACT FROM AUTHOR]

In accordance with China's commitments to reduce greenhouse gas emissions under the Paris Agreement, it is important to establish a fair and effective carbon emission allocation mechanism; this would help to achieve China's 2030 "carbon peak" target. Here, the fixed cost allocation model (FCAM) was used to allocate carbon emission quotas to public buildings in China in 2030, based on the principles of equity and efficiency. By comparing these provincial allocation results with those obtained using zero-sum data envelope analysis (ZSG-DEA), optimal carbon emission quotas were proposed for the public building sectors of thirty Chinese provinces. The results revealed large differences, with the public buildings of Guangdong having the highest quota (11.39%) and those of Xinjiang having the lowest (0.08%). Additionally, Heilongjiang, Inner Mongolia, and Liaoning were revealed to be under high pressure with regard to the reduction of emissions from their public buildings; Heilongjiang was predicted to require the highest reduction, exhibiting a need to reduce 34 million tons of emissions. These findings will help provide new ideas for relevant policy makers to formulate fair and effective carbon allowance allocation plans. • We propose a carbon emission allocation plan for public buildings in China in 2030. • Proposal of optimal carbon emission allowances using fixed cost allocation model. • Provinces with higher input-output efficiency, such as Guangdong, Jiangsu have higher allocations. • Proposes a low-carbon development path for China in 2030 by region. [ABSTRACT FROM AUTHOR]

Due to large energy consumption and carbon emissions (ECCE) in the building sector, there is huge potential for carbon emission reduction, and this will strongly influence peak carbon emissions and carbon neutrality in the future. To get a better sense of the current research situation and future trends and to provide a valuable reference and guidance for subsequent research, this study presents a summary of carbon peak and carbon neutrality (CPCN) in buildings using a bibliometric approach. Three areas are addressed in the review through the analysis of 364 articles published from 1990–2021: (1) Which countries, institutions, and individuals have conducted extensive and in-depth research on CPCN in buildings, and what is the status quo of their collaboration and contributions? (2) What subjects and topics have aroused wide interest and enthusiasm among scholars, and what are their time trajectories? (3) What journals and authors have grabbed the attention of many scholars, and what are the research directions related to them? Moreover, we propose future research directions. Filling these gaps will enrich the research body of CPCN and overcome current limitations by developing more methods and exploring other practical applications. [ABSTRACT FROM AUTHOR]

• Carbon emissions and human development were coupled for sustainability. • Approaches on exploring the coupling effect were proposed for the first time. • Data on China's provincial-level human development index were detailed. • Coupling status was discussed via the clustering quadrant method. Lessening energy-related carbon emissions has become a crucial measure to achieve Chinese carbon neutrality. This study is the first to construct a Difference in Carbon pressures-adjusted Human Development Index (DCHDI) model for the purpose of exploring the coupling effect between carbon emissions and human development variety from 2000 to 2019 in Chinese provinces. We demonstrate the following. (1) The total energy-related carbon footprint of 30 provinces in China reached 10.2 billion tons in 2019, with an average annual growth rate of 6.93% over the past two decades; and the provinces with the highest carbon emissions per capita are InnerMongolia, Ningxia, and Shanxi. (2) At the provincial level, we observed that the Human Development Index (HDI), which includes life expectancy, education, and income, has been rising, while Beijing, Shanghai, and Tianjin entered the super-high HDI level before 2008. (3) The entire coupling effect of 30 Chinese provinces has been broadly fortified in the last 20 years, but the growth rate of DCHDI values in 2011–2019 has slowed down compared with that in 2000–2010; the clustering phenomenon demonstrated that this discovery is associated with historical peaks in total carbon emissions. (4) The coordination degree of carbon emissions per capita and HDI was verified, and 96% of the data points were found in the range of super high coupling coordination degree. Overall, this study provides the government with worthwhile guidance for decision-making and carbon reduction strategies for other countries struggling to advance human sustainable development. [ABSTRACT FROM AUTHOR]

Clarifying the critical driving factors and the driving mechanism for building carbon emissions is fundamental for carbon peak and carbon neutrality prediction. This study comprehensively identifies 23 representative factors using the literature research and questionnaire survey method. Then, by coupling the decision-making trial and evaluation laboratory (DEMATEL) method and the interpretive structural model (ISM), an integrated DEMATEL-ISM model is developed. The proposed model is further employed to quantify the causal relationships among the factors and establish a multi-level recursive structure model to determine the action mechanism of those drivers. The results show that the 11 cause factors, 12 effect factors and the three most important factors including the economic development level, building end-use energy consumption and end-use energy intensity are identified based on the calculated cause and center degree. Based on the obtained hierarchy, the 23 factors are divided into six levels, among which the population factors, the economic development, the urbanization level and the share of the tertiary sector are the root factors leading to the building carbon emissions. In comparison, policy factors are the most critical inhibiting factors. This study can not only promote the theory and model development for the driving mechanism of carbon emissions, but also help decision-makers develop scientific carbon reduction strategies. • Establishes an integrated DEMATEL-ISM model by coupling the DEMATEL method with the ISM. • Identifies the representative factors affecting the building carbon emissions from the systematic perspective. • Explores the significance of the factors and their intricate interactive mechanism. • Population factors, socio-economic development, urbanization level and the tertiary sector share are the fundamental factors. • Policy factors are the most critical inhibiting factors. [ABSTRACT FROM AUTHOR]

Carbon mitigation effectiveness in the building sector profoundly determines the achievement of the "Dual carbon" target. However, the timetable and roadmap for the building sector to achieve such a target are still lacking. This study constructs a STIRPAT-PLS model framework to clarify the impact of the key factors from various dimensions on building carbon emissions across sub-sectors. Then, a dynamic scenario simulation model is established and applied in China to explore the dynamic evolutionary paths, and the timetable and roadmap are ultimately formulated. The results show that building sector will probably peak at 2.99 (± 0.09) Gt CO 2 in 2036 (± 1). Rural residential buildings will peak earliest in 2026 (± 1), followed by urban residential and commercial buildings: in 2036 (± 2) and 2038 (± 1). Achieving carbon neutrality will require the building sector to peak its carbon emissions in 2026 with 2.16–2.40 Gt CO 2. The remaining 0.56–0.81 Gt CO 2 by 2060 will be offset by negative carbon technologies. Dynamic sensitivity analysis shows that building floor space per capita and energy intensity significantly promote the emission peaks, and population and building floor space per capita markedly impact the peaking times. This study can promote the development of the theory and model for carbon emissions prediction. It can also offer a scientific basis for governments to set effective carbon-reduction targets and paths. [Display omitted] • Constructing a STIRPAT-PLS model to clarify the impact of critical factors on building carbon emissions. • Establishing a dynamic scenario simulation model by combining the Monte Carlo simulation and scenario analysis. • Building sector will probably peak at 2.99 (± 0.09) Gt CO 2 in 2036 (± 1). • Achieving carbon neutrality requires the building sector to peak its carbon emissions in 2026 with 2.16–2.40 Gt CO 2. • Building floor space per capita and energy intensity significantly promote the emission peaks. [ABSTRACT FROM AUTHOR]

[Display omitted] • Establishes an integrated dynamic emission assessment model by coupling end-use energy model and system dynamics model. • Explores the dynamic interaction mechanism between macrolevel and microlevel factors as well as technical options. • Commercial buildings will probably hit the emission peak at 1.28Gt CO 2 in 2037 under the BAU scenario. • Lighting and cooling will contribute over 70% to the carbon emission growth. • Technological progress, clean energy, and electrification rate play significant roles in boosting emission peak and peaking time. Carbon-mitigation in the commercial building sector is critical to carbon peaking and carbon neutral commitment. However, there has been little scientific focus on long-term evolutionary trajectories and peak path in this sector. This study innovatively develops an integrated dynamic emission assessment model (IDEAM) by combining the system dynamics model with the bottom-up end-use energy model. Moreover, the IDEAM is combined with the scenario analysis approach to model the dynamic evolution of Chinese commercial building carbon emissions toward 2060. The results show that commercial building carbon emissions will peak at 1.28 Gigatons (Gt) of CO 2 in 2037 under the baseline scenario and will advance toward 2029 with an emissions peak of 0.98 Gt CO 2 under the low-carbon scenario. Cooling and lighting are the two end-uses that contribute most to the growth of carbon emissions at over 70%. These two end-uses indicate different carbon-abatement potentials across climate zones. Sensitivity analysis reveals that promoting technological progress, increasing the share of clean energy, and improving low-carbon awareness are major ways to facilitate the early realization of carbon peaks and carbon neutrality. This study provides a deeper understanding of possible emission pathways and could assist policy-makers in devising scientific carbon mitigation plans. [ABSTRACT FROM AUTHOR]

Contributions of different end-use activities to carbon intensity changes in global commercial building operations in (a) 2000–2010 and (c) 2010–2019; (b) impacts of different end-use activities on decarbonizing the operational carbon intensity across different countries in 2000–2019. [Display omitted] • The carbon intensity of commercial building operations in 16 economies declined 1.9 % yr−1 in 2000–2019. • Emission factors and industrial structure were the key to decarbonizing the building operations. • Energy intensity (e.g., heating: −14.3 kgCO 2 /m2/yr) has pushed global decarbonization since the 2010 s. • Decarbonization level in 16 economies was 230.3 MtCO 2 /yr with a decarbonization efficiency of 10.1%; • Electricity decarbonization will be critical to achieving global carbon neutrality in commercial buildings. Building operations will be the most critical step in completing the "last mile" of global carbon neutrality. To seek the best practical path to decarbonize commercial building operations, this study assesses the decarbonization progress of commercial building operations in 16 countries over the last two decades considering socioeconomic, technical, climatic and end-use factors through the decomposing structural decomposition method. The results reveal that (1) the average carbon intensity of commercial building operations in 16 countries has maintained an annual decline of 1.94% throughout the period 2000–2019, and emission factors and industrial structures were generally the key to decarbonizing commercial building operations; (2) energy intensity effects have started to promote global decarbonization in commercial building operations since 2010, with contributions from space heating [-14.33 kg of carbon dioxide per square meter per year (kgCO 2 /m2/yr)], service lighting (-5.29 kgCO 2 /m2/yr), appliances and others (-2.85 kgCO 2 /m2/yr), and space cooling (-1.24 kgCO 2 /m2/yr); and (3) the total decarbonization of commercial building operations worldwide was 230.28 mega-tons of carbon dioxide per yr, with a decarbonization efficiency of 10.05% in 2001–2019. Moreover, the robustness of this decarbonization assessment is tested using the typical index decomposition analysis and the decarbonization strategies of global commercial building operations are reviewed. Overall, this study assesses the global historical progress in decarbonizing commercial building operations and closes the relevant gap, and it helps plan the stepwise carbon neutral pathway of future global buildings by the mid-century. [ABSTRACT FROM AUTHOR]

Carbon-reduction effect of the urban residential building sector is crucial to the carbon neutrality target. This study aims to explore the interaction mechanism among influencing factors and simulate the future evolutionary trajectories of urban residential building carbon emissions (URBCE). An integrated dynamic emission assessment (IDEA) model is innovatively established by coupling the system dynamics (SD) model and a bottom-up end-use decomposition model. Combining with the scenario analysis approach, this IDEA model is applied in China's urban residential building sector from 2000 to 2060. Results show that under the baseline scenario, the URBCE will fail to peak before 2030 but will peak at 1.19 Bt CO 2 in 2037. In comparison, it will peak at 0.79 Bt CO 2 in 2025 and decline to 0.17 Bt CO 2 in 2060 under carbon-neutral scenario, which can be neutralized by negative carbon technologies. Different end-uses and climate zones show marked discrepancies in emission-reduction potential, with the contribution of heating and appliances being over 50%. Sensitivity analyses shows that the low-carbon awareness, electrification rate, proportion of clean energy generation and technological progress contribute positively to the early peak of URBCE. This study provides a deeper understanding of China's potential peaking paths and can assist policy-makers in better evaluating emission paths for other nations and regions. [Display omitted] • Develops an IDEA model by combining system dynamics model and LEAP model. • Explores the interaction and feedback mechanism among different levels of factors. • Simulates the URBCE by combining the IDEA model and scenario analysis approach. • Urban residential buildings will peak at 1.19 Bt CO 2 in 2037 under the BAU scenario. • Different end-uses and climate zones show marked discrepancies in emission-reduction potential. [ABSTRACT FROM AUTHOR]

(a–f) Changes of carbon reductions of commercial building operations at the provincial level and (g) the difference with the nation-based results (2001–2016). [Display omitted] • Provincial carbon intensity of commercial building operations grew 2.88 % yr−1 in 2001–2016. • Northeast and north China mitigated the most in carbon intensity and emissions, respectively. • Southwest China showed the highest ratio of carbon reductions to carbon emissions at 29.53%. • The total reduction of China's commercial building operation was 1.38 GtCO 2 in 2001–2016. • Annual provincial reductions peaked in 2013, one year earlier than the national result. The growing energy consumption in commercial building operations has slowed the pace of carbon reduction in the building sector, which has hindered China's movement towards peaking emissions by 2030 and carbon neutrality by mid-century. Considering the technical, socio-economic, climatic, and behavioral factors, this study evaluates the carbon reduction changes of commercial building operations in China's 30 provinces during the period 2001–2016. An assessment framework of the reduction intensity, amount, and efficiency has been built by carbon intensity decomposition. It shows that (1) the average provincial carbon intensity of commercial building operations kept rising by 2.88% per year from 2000 to 2016; (2) provinces of northeast and north China, respectively, took the lead in reduction intensity and amount at 17.09 kg of carbon dioxide per square meter and 73.79 megatonnes of carbon dioxide (MtCO 2) from 2001 to 2016. Meanwhile, the greatest efficiency of carbon reduction was seen in provinces of southwest China with the highest reductions-emissions ratio being 29.53%; (3) compared to the national level results, the annual carbon reductions based on provincial units hit their peak one year earlier at 167.35 MtCO 2 in 2013, although similar emission drivers have been observed. Moreover, effective practices by local governments have been summarized for energy efficiency promotion in commercial building operations. Overall, this study makes a reference for other economies to assess the historical carbon reduction in the building operation, which provides policymakers with insights into balanced and targeted emission reduction strategies towards a low-carbon transition in commercial building sector. [ABSTRACT FROM AUTHOR]