The overall objective of this paper is to scrutinize previous economic models used to assess the economic costs of cli-mate policy. We pay particular attention to the way in which different model structures and assump...The overall objective of this paper is to scrutinize previous economic models used to assess the economic costs of cli-mate policy. We pay particular attention to the way in which different model structures and assumptions affect cost es-timates, and highlight the limitations and the strengths of different types of modelling approaches. The paper begins by briefly discussing the concept of economic costs, different cost categories (i.e., direct costs, partial equilibrium costs and general equilibrium costs), and the various model approaches that can be used to assess the economic impacts of climate policy (e.g., top-down versus bottom-up models). A systematic review of the main assumptions and methodo-logical choices that underlie different reported cost estimates is presented, and we distinguish between five main types of climate policy cost drivers: a) the baseline scenario;b) the structural characteristics of the models;c) the representa-tion of technological change (e.g., endogenous or exogenous);d) the design of climate policy;and e) the inclusion of non-market costs and benefits. The analysis shows that all these elements help explain model outcomes.展开更多
Background:In China,malaria has been posing a significant economic burden on households.To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of ...Background:In China,malaria has been posing a significant economic burden on households.To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of malaria elimination program in China.Methods:A number of study sites(eight counties in five provinces)were selected from the malaria endemic area in China,representing the different levels of malaria incidence,risk classification,economic development.A number of households with malaria cases(n=923)were surveyed during the May to December in 2012 to collect information on malaria economic burden.Descriptive statistics were used to characterize the basic profiles of selected malaria cases in terms of their gender,age group,occupation and malaria type.The malaria economic costs were evaluated by direct and indirect costs.Comparisons were carried out by using the chi-square test(or Z-test)and the Mann-Whitney U test among malaria cases with reference to local/imported malaria patients,hospitalized/out patients,and treatment hospitals.Results:The average cost of malaria per case was 1691.23 CNY(direct cost was 735.41 CNY and indirect cost was 955.82 CNY),which accounted for 11.1%of a household’s total income.The average costs per case for local and imported malaria were 1087.58 CNY and 4271.93 CNY,respectively.The average cost of a malaria patient being diagnosed and treated in a hospital at the county level or above(3975.43 CNY)was 4.23 times higher than that of malaria patient being diagnosed and treated at a village or township hospital(938.80 CNY).Conclusion:This study found that malaria has been posing a significant economic burden on households in terms of direct and indirect costs.There is a need to improve the effectiveness of interventions in order to reduce the impact costs of malaria,especially of imported infections,in order to eliminate the disease in China.展开更多
Absence of wastewater and solid waste facilities impacts the quality of life of many people in developing countries. Implementation of these facilities will benefit public health, water quality, livelihoods and proper...Absence of wastewater and solid waste facilities impacts the quality of life of many people in developing countries. Implementation of these facilities will benefit public health, water quality, livelihoods and property value. Additional benefits may result from the potential recovery of valuable resources from wastewater and solid waste, such as compost, energy, phosphorus, plastics and paper. Improving water quality through implementation of wastewater and solid waste interventions requires, among others, an analysis of i) sources of pollution, ii) mitigating measures and resource recovery potentials and their effect on water quality and health, and iii) benefits and costs of interventions. We present an integrated approach to evaluate costs and benefits of domestic and industrial wastewater and solid waste interventions. To support a policy maker in formulating a cost and environmentally effective approach, we quantified the impact of these interventions on 1) water quality improvement, 2) resource recovery potential, and 3) monetized benefits versus costs. The integration of technical, hydrological, agronomical and socio-economic elements to derive these three tangible outputs in a joint approach is a novelty. The approach is demonstrated using the heavily polluted Indonesian Upper Citarum River in the Bandung region. Domestic interventions, applying simple (anaerobic filter) technologies, were economically most attractive with a benefit cost ratio (BCR) of 3.2, but could not reach target water quality standards. To approach the target water quality, both advanced domestic (nutrient removal systems) and industrial wastewater treatment interventions were required, leading to a BCR of 2. We showed that benefits from selling recovered resources represent here an additional driver for improving water quality and outweigh the additional costs for resource recovery facilities. While included benefits captured some of the major items, these may have been undervalued. Based on these findings, water quality interventions justify their costs and are socially and economically beneficial.展开更多
Sand barriers are the most widely used mechanical implements for wind-blown sand control and desertification prevention.However,there is no standard quantitative cost analysis of the sizes and materials required for s...Sand barriers are the most widely used mechanical implements for wind-blown sand control and desertification prevention.However,there is no standard quantitative cost analysis of the sizes and materials required for sand barriers.In this study,based on the original land grid division model for optimal resource utilization,we calculated the total side lengths of square and regular hexagonal sand barriers with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m in a desertified region of the Shapotou area on the southeastern edge of the Tengger Desert,China.Then,through literature review and social survey,we obtained the material cost and material utilization amount of sand barriers with different materials and sizes.Finally,we calculated the costs of square and regular hexagonal sand barriers comprised of wheat straw,corn stalk,Salix mongolica,poly lactic acid,magnesium cement,and high-density polyethylene,with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m.The results show that the material cost of regular hexagonal corn stalk sand barriers with the size of 3.0 m×3.0 m is the lowest,while the material cost of square magnesium cement sand barriers with the size of 1.0 m×1.0 m is the highest.When using the same material,the cost of regular hexagonal sand barriers is lower than that of square sand barriers with the same size.When using the same size,the cost of sand barriers with corn stalk material is lower than that of sand barriers with other materials.Based on the above analysis,we can conclude that the economic benefits of regular hexagonal sand barriers are greater than those of square sand barriers.This study provides a theoretical basis for accurately calculating the material cost of sand barriers,particularly for the estimated cost of mechanized sand barrier engineering projects.展开更多
Plastic pollution is a major problem: it damages health, reduces ecosystem services, and affects local economies. Despite its importance, available valuation efforts have focused primarily on the damages caused by pla...Plastic pollution is a major problem: it damages health, reduces ecosystem services, and affects local economies. Despite its importance, available valuation efforts have focused primarily on the damages caused by plastic in marine environments. Far less is known about the effects of plastic waste in inland settings. This paper addresses this gap by estimating in monetary terms the damages caused by the inappropriate disposal of plastic waste in an inland context. The study area is located along a canal that crosses N’Djamena, the capital of Chad. Using data from a primary survey and applying standard valuation techniques, the paper estimates the social cost of plastic pollution at over USD3000 per ton in 2020. In addition, it shows that the impacts of plastic waste vary significantly across the study area: households residing within 20 meters of the canal bear more than 75 percent of the total damages. The paper identifies the main valuation challenges and proposes recommendations to reduce plastic waste damages.展开更多
BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used ga...BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used gastrointestinal endoscopes were selected from five high-volume endoscopy units and precleaned by a traditional precleaning bucket(group T)or a disposable endoscope bedside precleaning kit(group D).Each group was further subdivided based on the replacement frequency of the cleaning solution,which was replaced every time in subgroups T1 and D1 and every several times in subgroups Ts and Ds.The adenosine triphosphate(ATP)level and residual proteins were measured three times:Before and after precleaning and after manual cleaning.RESULTS After precleaning,the precleaning kit significantly reduced the ATP levels(P=0.034)and has a more stable ATP clearance rate than the traditional precleaning bucket.The precleaning kit also saved a quarter of the cost of enzymatic detergent used during the precleaning process.After manual cleaning,the ATP levels were also significantly lower in the precleaning kit group than in the traditional precleaning bucket group(P<0.05).Meanwhile,the number of uses of the cleaning solution(up to four times)has no significant impact on the cleaning effect(P>0.05).CONCLUSION Considering its economic cost and cleaning effect,the use of a disposable endoscope bedside precleaning kit can be an optimal option in the precleaning stage with the cleaning solution being replaced several times in the manual cleaning stage.展开更多
The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing e...The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing environmental damage at each stage before being denitrifled to N2. We propose to construct a parallel economic nitrogen cascade (ENC) in which economic impacts of nitrogen fluxes can be estimated by the costs associated with each stage of the chemical cascade. Using economic data for the benefits of damage avoided and costs of mitigation in the Chesapeake Bay basin, we have constructed an economic nitrogen cascade for the region. Since a single tonne of nitrogen can cascade through the system, the costs also cascade.Therefore evaluating the benefits of mitigating a tonne of reactive nitrogen released needs to consider the damage avoided in all of the ecosystems through which that tonne would cascade.The analysis reveals that it is most cost effective to remove a tonne of nitrogen coming from combustion since it has the greatest impact on human health and creates cascading damage through the atmospheric, terrestrial, aquatic and coastal ecosystems. We will discuss the implications of this analysis for determining the most cost effective policy option for achieving environmental quality goals.展开更多
In industrial plants, ships, and buildings, a large amount of gas and air ducts are applied for equipment connection, HVAC, medium transport, and exhaust, etc. These ducts can be designed in varied cross-sectional sha...In industrial plants, ships, and buildings, a large amount of gas and air ducts are applied for equipment connection, HVAC, medium transport, and exhaust, etc. These ducts can be designed in varied cross-sectional shapes, such as round or rectangle. The author reveals through geometric calculation of the duct cross-sectional shapes and engineering experiences that the round cross-section is an optimal shape in the duct system. The round duct has the shorter perimeter than the other cross-sectional shape ducts and the stronger structure in the same working condition. The material saving of the round duct due to the shorter perimeter is quantitatively determined. In the pater, it is shown that the round duct is economically attractive. The economic analysis for the material cost saving is illustrated by an example. For a long duct system, the material and material cost savings are significant. It is suggested that the round duct in the gas and air duct system should have priority as long as the field conditions are allowed. In the paper, the material cost saving is also converted to PW, AW, and FW used for LCC economic analysis.展开更多
A two temperature CO_(2) refrigeration system with economizer is proposed and compared with the traditional dual-temperature CO_(2) refrigeration system based on energy consumption,exergy and economic analysis.Using g...A two temperature CO_(2) refrigeration system with economizer is proposed and compared with the traditional dual-temperature CO_(2) refrigeration system based on energy consumption,exergy and economic analysis.Using genetic algorithm multi-objective optimization method,taking the COP,exergy loss and total economic cost as the objective functions to find the best design conditions of the two systems.The Pareto fronts are obtained at different ambient temperatures.Technique for order preference by similarity to an ideal solution decision-making method is adopted to determine the optimum state points.The simulation results show that when operating at different ambient temperatures,the introduction of economizer can improve COP,reduce exergy loss and the overall economic cost rate of the two-temperature CO_(2) refrigeration system.In addition,economic analyses take the impact of carbon dioxide emission cost and electricity price into consideration.The results indicate that with the increase of CO_(2) emission cost and electricity price,the hourly economic cost of both systems increases,but the hourly economic cost of the two-temperature CO_(2) refrigeration system with economizer system is always lower than that of conventional two-temperature CO_(2) refrigeration system.展开更多
Understanding mitigation ambitions of the Nationally Determined Contributions(NDCs)should include both the equity of supporting the Paris Agreement goals and the costs of achieving the proposed mitigation targets.This...Understanding mitigation ambitions of the Nationally Determined Contributions(NDCs)should include both the equity of supporting the Paris Agreement goals and the costs of achieving the proposed mitigation targets.This study presents a new framework that combines equity and economic costs to compare and analyze mitigation ambitions of Parties'updated NDCs.Under representative 2℃ and 1.5℃ pathways,this framework uses multiple equity-principled allocations to derive the alignment of the updated NDCs with the Paris Agreement goals,and further applies a computable general equilibrium model to assess the economic costs of implementing the updated NDCs.The results show that global 2030 emissions may meet the selected global 2℃ pathway if all Parties achieve their most ambitious mitigation efforts,but there is still an emissions gap of 10-15 GtCO_(2) to follow the selected 1.5℃ pathway.From the perspective of equity,the updated NDCs of the USA,the EU(including the UK in this study),and Japan lack ambition with respect to‘equal cumulative per capita emissions’under 2℃ and do not align with any equity principles under 1.5℃.The updated NDCs of China,India,Brazil and South Africa reflect their claims to‘equity’and‘common but differentiated responsibilities’.From the perspective of economic costs,the GDP and welfare losses of China,Brazil and South Africa incurred by achieving the updated NDCs are not lower than those of the three developed Parties.China's GDP loss is estimated at 0.43%-0.55%in 2030,which is higher than that of the USA(0.30%-0.38%)and the EU(0.25%-0.28%).This study suggests that developed Parties take the lead in further ratcheting up the NDCs and strengthen financial and technological support to developing countries so that the world could close the gap to 1.5℃.展开更多
文摘The overall objective of this paper is to scrutinize previous economic models used to assess the economic costs of cli-mate policy. We pay particular attention to the way in which different model structures and assumptions affect cost es-timates, and highlight the limitations and the strengths of different types of modelling approaches. The paper begins by briefly discussing the concept of economic costs, different cost categories (i.e., direct costs, partial equilibrium costs and general equilibrium costs), and the various model approaches that can be used to assess the economic impacts of climate policy (e.g., top-down versus bottom-up models). A systematic review of the main assumptions and methodo-logical choices that underlie different reported cost estimates is presented, and we distinguish between five main types of climate policy cost drivers: a) the baseline scenario;b) the structural characteristics of the models;c) the representa-tion of technological change (e.g., endogenous or exogenous);d) the design of climate policy;and e) the inclusion of non-market costs and benefits. The analysis shows that all these elements help explain model outcomes.
基金supported by the National Natural Science Foundation of China(No.81101280)the National Special Science and Technology Project for Major Infectious Diseases of China(Grant Nos.2012ZX10004-220,2008ZX10004-011,and 2012ZX10004-201)+1 种基金the China UK Global Health Support Programme(GHSP-CS-OP101)-China’s Experiences in Control of Malaria and Schistosomiasis:Relevant to LMICs through Distillation,Synthesis and Dissemination Approaches,the Public Health Overseas Fund,the Bureau of Health,Shanghai(Grant No.GWHW201216)the Shanghai Public Health Improvement Action Plan 2015–2017,and the Global Fund Project in China.The funders had no role in the study design,data collection and analysis,decision to publish,or preparation of the paper.
文摘Background:In China,malaria has been posing a significant economic burden on households.To evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of malaria elimination program in China.Methods:A number of study sites(eight counties in five provinces)were selected from the malaria endemic area in China,representing the different levels of malaria incidence,risk classification,economic development.A number of households with malaria cases(n=923)were surveyed during the May to December in 2012 to collect information on malaria economic burden.Descriptive statistics were used to characterize the basic profiles of selected malaria cases in terms of their gender,age group,occupation and malaria type.The malaria economic costs were evaluated by direct and indirect costs.Comparisons were carried out by using the chi-square test(or Z-test)and the Mann-Whitney U test among malaria cases with reference to local/imported malaria patients,hospitalized/out patients,and treatment hospitals.Results:The average cost of malaria per case was 1691.23 CNY(direct cost was 735.41 CNY and indirect cost was 955.82 CNY),which accounted for 11.1%of a household’s total income.The average costs per case for local and imported malaria were 1087.58 CNY and 4271.93 CNY,respectively.The average cost of a malaria patient being diagnosed and treated in a hospital at the county level or above(3975.43 CNY)was 4.23 times higher than that of malaria patient being diagnosed and treated at a village or township hospital(938.80 CNY).Conclusion:This study found that malaria has been posing a significant economic burden on households in terms of direct and indirect costs.There is a need to improve the effectiveness of interventions in order to reduce the impact costs of malaria,especially of imported infections,in order to eliminate the disease in China.
文摘Absence of wastewater and solid waste facilities impacts the quality of life of many people in developing countries. Implementation of these facilities will benefit public health, water quality, livelihoods and property value. Additional benefits may result from the potential recovery of valuable resources from wastewater and solid waste, such as compost, energy, phosphorus, plastics and paper. Improving water quality through implementation of wastewater and solid waste interventions requires, among others, an analysis of i) sources of pollution, ii) mitigating measures and resource recovery potentials and their effect on water quality and health, and iii) benefits and costs of interventions. We present an integrated approach to evaluate costs and benefits of domestic and industrial wastewater and solid waste interventions. To support a policy maker in formulating a cost and environmentally effective approach, we quantified the impact of these interventions on 1) water quality improvement, 2) resource recovery potential, and 3) monetized benefits versus costs. The integration of technical, hydrological, agronomical and socio-economic elements to derive these three tangible outputs in a joint approach is a novelty. The approach is demonstrated using the heavily polluted Indonesian Upper Citarum River in the Bandung region. Domestic interventions, applying simple (anaerobic filter) technologies, were economically most attractive with a benefit cost ratio (BCR) of 3.2, but could not reach target water quality standards. To approach the target water quality, both advanced domestic (nutrient removal systems) and industrial wastewater treatment interventions were required, leading to a BCR of 2. We showed that benefits from selling recovered resources represent here an additional driver for improving water quality and outweigh the additional costs for resource recovery facilities. While included benefits captured some of the major items, these may have been undervalued. Based on these findings, water quality interventions justify their costs and are socially and economically beneficial.
基金supported by the Research Program of Technology and Demonstration of Desert Margin Expansion Zone Stabilization for Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences(XDA23060201)。
文摘Sand barriers are the most widely used mechanical implements for wind-blown sand control and desertification prevention.However,there is no standard quantitative cost analysis of the sizes and materials required for sand barriers.In this study,based on the original land grid division model for optimal resource utilization,we calculated the total side lengths of square and regular hexagonal sand barriers with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m in a desertified region of the Shapotou area on the southeastern edge of the Tengger Desert,China.Then,through literature review and social survey,we obtained the material cost and material utilization amount of sand barriers with different materials and sizes.Finally,we calculated the costs of square and regular hexagonal sand barriers comprised of wheat straw,corn stalk,Salix mongolica,poly lactic acid,magnesium cement,and high-density polyethylene,with the sizes of 1.0 m×1.0 m,2.0 m×2.0 m,and 3.0 m×3.0 m.The results show that the material cost of regular hexagonal corn stalk sand barriers with the size of 3.0 m×3.0 m is the lowest,while the material cost of square magnesium cement sand barriers with the size of 1.0 m×1.0 m is the highest.When using the same material,the cost of regular hexagonal sand barriers is lower than that of square sand barriers with the same size.When using the same size,the cost of sand barriers with corn stalk material is lower than that of sand barriers with other materials.Based on the above analysis,we can conclude that the economic benefits of regular hexagonal sand barriers are greater than those of square sand barriers.This study provides a theoretical basis for accurately calculating the material cost of sand barriers,particularly for the estimated cost of mechanized sand barrier engineering projects.
文摘Plastic pollution is a major problem: it damages health, reduces ecosystem services, and affects local economies. Despite its importance, available valuation efforts have focused primarily on the damages caused by plastic in marine environments. Far less is known about the effects of plastic waste in inland settings. This paper addresses this gap by estimating in monetary terms the damages caused by the inappropriate disposal of plastic waste in an inland context. The study area is located along a canal that crosses N’Djamena, the capital of Chad. Using data from a primary survey and applying standard valuation techniques, the paper estimates the social cost of plastic pollution at over USD3000 per ton in 2020. In addition, it shows that the impacts of plastic waste vary significantly across the study area: households residing within 20 meters of the canal bear more than 75 percent of the total damages. The paper identifies the main valuation challenges and proposes recommendations to reduce plastic waste damages.
文摘BACKGROUND Precleaning is a key step in endoscopic reprocessing.AIM To develop an effective and economic endoscope cleaning method by using a disposable endoscope bedside precleaning kit.METHODS Altogether,228 used gastrointestinal endoscopes were selected from five high-volume endoscopy units and precleaned by a traditional precleaning bucket(group T)or a disposable endoscope bedside precleaning kit(group D).Each group was further subdivided based on the replacement frequency of the cleaning solution,which was replaced every time in subgroups T1 and D1 and every several times in subgroups Ts and Ds.The adenosine triphosphate(ATP)level and residual proteins were measured three times:Before and after precleaning and after manual cleaning.RESULTS After precleaning,the precleaning kit significantly reduced the ATP levels(P=0.034)and has a more stable ATP clearance rate than the traditional precleaning bucket.The precleaning kit also saved a quarter of the cost of enzymatic detergent used during the precleaning process.After manual cleaning,the ATP levels were also significantly lower in the precleaning kit group than in the traditional precleaning bucket group(P<0.05).Meanwhile,the number of uses of the cleaning solution(up to four times)has no significant impact on the cleaning effect(P>0.05).CONCLUSION Considering its economic cost and cleaning effect,the use of a disposable endoscope bedside precleaning kit can be an optimal option in the precleaning stage with the cleaning solution being replaced several times in the manual cleaning stage.
文摘The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing environmental damage at each stage before being denitrifled to N2. We propose to construct a parallel economic nitrogen cascade (ENC) in which economic impacts of nitrogen fluxes can be estimated by the costs associated with each stage of the chemical cascade. Using economic data for the benefits of damage avoided and costs of mitigation in the Chesapeake Bay basin, we have constructed an economic nitrogen cascade for the region. Since a single tonne of nitrogen can cascade through the system, the costs also cascade.Therefore evaluating the benefits of mitigating a tonne of reactive nitrogen released needs to consider the damage avoided in all of the ecosystems through which that tonne would cascade.The analysis reveals that it is most cost effective to remove a tonne of nitrogen coming from combustion since it has the greatest impact on human health and creates cascading damage through the atmospheric, terrestrial, aquatic and coastal ecosystems. We will discuss the implications of this analysis for determining the most cost effective policy option for achieving environmental quality goals.
文摘In industrial plants, ships, and buildings, a large amount of gas and air ducts are applied for equipment connection, HVAC, medium transport, and exhaust, etc. These ducts can be designed in varied cross-sectional shapes, such as round or rectangle. The author reveals through geometric calculation of the duct cross-sectional shapes and engineering experiences that the round cross-section is an optimal shape in the duct system. The round duct has the shorter perimeter than the other cross-sectional shape ducts and the stronger structure in the same working condition. The material saving of the round duct due to the shorter perimeter is quantitatively determined. In the pater, it is shown that the round duct is economically attractive. The economic analysis for the material cost saving is illustrated by an example. For a long duct system, the material and material cost savings are significant. It is suggested that the round duct in the gas and air duct system should have priority as long as the field conditions are allowed. In the paper, the material cost saving is also converted to PW, AW, and FW used for LCC economic analysis.
基金supported by the National Natural Science Foundation of China (Grant No. 51776110)。
文摘A two temperature CO_(2) refrigeration system with economizer is proposed and compared with the traditional dual-temperature CO_(2) refrigeration system based on energy consumption,exergy and economic analysis.Using genetic algorithm multi-objective optimization method,taking the COP,exergy loss and total economic cost as the objective functions to find the best design conditions of the two systems.The Pareto fronts are obtained at different ambient temperatures.Technique for order preference by similarity to an ideal solution decision-making method is adopted to determine the optimum state points.The simulation results show that when operating at different ambient temperatures,the introduction of economizer can improve COP,reduce exergy loss and the overall economic cost rate of the two-temperature CO_(2) refrigeration system.In addition,economic analyses take the impact of carbon dioxide emission cost and electricity price into consideration.The results indicate that with the increase of CO_(2) emission cost and electricity price,the hourly economic cost of both systems increases,but the hourly economic cost of the two-temperature CO_(2) refrigeration system with economizer system is always lower than that of conventional two-temperature CO_(2) refrigeration system.
基金supported by the National Key R&D Program of China(2017YFA0605302)the National Natural Science Foundation of China(72174105)support of the Science Foundation of China University of Petroleum,Beijing(2462020YXZZ038).
文摘Understanding mitigation ambitions of the Nationally Determined Contributions(NDCs)should include both the equity of supporting the Paris Agreement goals and the costs of achieving the proposed mitigation targets.This study presents a new framework that combines equity and economic costs to compare and analyze mitigation ambitions of Parties'updated NDCs.Under representative 2℃ and 1.5℃ pathways,this framework uses multiple equity-principled allocations to derive the alignment of the updated NDCs with the Paris Agreement goals,and further applies a computable general equilibrium model to assess the economic costs of implementing the updated NDCs.The results show that global 2030 emissions may meet the selected global 2℃ pathway if all Parties achieve their most ambitious mitigation efforts,but there is still an emissions gap of 10-15 GtCO_(2) to follow the selected 1.5℃ pathway.From the perspective of equity,the updated NDCs of the USA,the EU(including the UK in this study),and Japan lack ambition with respect to‘equal cumulative per capita emissions’under 2℃ and do not align with any equity principles under 1.5℃.The updated NDCs of China,India,Brazil and South Africa reflect their claims to‘equity’and‘common but differentiated responsibilities’.From the perspective of economic costs,the GDP and welfare losses of China,Brazil and South Africa incurred by achieving the updated NDCs are not lower than those of the three developed Parties.China's GDP loss is estimated at 0.43%-0.55%in 2030,which is higher than that of the USA(0.30%-0.38%)and the EU(0.25%-0.28%).This study suggests that developed Parties take the lead in further ratcheting up the NDCs and strengthen financial and technological support to developing countries so that the world could close the gap to 1.5℃.
