Carbon Emission Transfer Research Articles

Identification of Key Carbon Emission Industries and Emission Reduction Control Based on Complex Network of Embodied Carbon Emission Transfers: The Case of Hei-Ji-Liao, China.

Similar to the problems surrounding carbon transfers that exist in international trade, there are severe carbon emission headaches in regional industrial systems within countries. It is essential for emission reduction control and regional industrial restructuring to clarify the relationship of carbon emissions flows between industrial sectors and identify key carbon-emitting industrial sectors. Supported by the input-output model (I-O model) and social network analysis (SNA), this research adopts input-output tables (2017), energy balance sheets (2021) and the energy statistics yearbooks (2021) of the three Chinese provinces of Hei-Ji-Liao to construct an Embodied carbon emission transfer network (ECETN) and determine key carbon-emitting industrial sectors with a series of complex network measurement indicators and analysis methods. The key abatement control pathways are obtained based on the flow relationships between the chains in the industrial system. The results demonstrate that the ECETNs in all three provinces of Hei-Ji-Liao are small-world in nature with scale-free characteristics (varying according to the power function). The key carbon emission industry sectors in the three provinces are identified through centrality, influence, aggregation and diffusion, comprising coal mining, the chemical industry, metal products industry, machinery manufacturing and transportation in Liaoning Province; coal mining, non-metal mining, non-metal products, metal processing and the electricity industry in Jilin Province; and agriculture, metal processing and machinery manufacturing in Heilongjiang. Additionally, key emission reduction control pathways in the three provinces are also identified based on embodied carbon emission flow relationships between industry sectors. Following the above findings, corresponding policy recommendations are proposed to tackle the responsibility of carbon reduction among industrial sectors in the province. Moreover, these findings provide some theoretical support and policy considerations for policymakers.

Study on the characteristics of embodied carbon emission transfer in China’s power sector based on input-output networks

Electricity is an essential factor of production. The trade of goods and services between different industrial sectors in different regions may lead to the transfer of embodied carbon emissions in the power sector, which makes the problem of “carbon leakage” widespread. As the world’s largest CO2 emitter, China’s systematic identification of the patterns and structural characteristics of embodied carbon transfer in its power sector is essential for reasonably defining emission reduction responsibilities and scientifically formulating emission reduction policies. Few studies have focused on interprovincial transfer characteristics of embodied carbon emissions in the power sector. Based on the multi-regional input-output tables of China in 2010, 2012, 2015, and 2017, this paper combined the complex network theory to construct the interprovincial power embodied carbon transfer networks (PECTNs1) of China, analyzed the topological nature, community structure and identified the key provinces in the networks with the help of complex network indicators. The results indicate that both direct and embodied carbon emissions from China’s power sector present an increasing trend during the study period. The scale and scope of power carbon emission transfer between provinces have been expanding, showing an transfer trend from west to east and north to south. China’s PECTNs have small-world characteristics. From 2010 to 2017, the sub-regional phenomenon in China’s PECTNs gradually decreased. In the network community, the provinces with stable relationships are close to each other and have closer carbon correlation. Coal resource-based and large economic provinces with high power demand tend to be the core of the networks. The position of Xinjiang in the networks is gradually prominent. According to the results of the study, differentiated carbon emission reduction schemes are formulated based on the roles played by different provinces to provide ideas for embodied carbon reduction among provinces in China’s power sector.

Tracing production carbon emission transfer through global value chains: Towards a top gainer principle

This study proposes the top gainer principle (TGP) and builds a calculation model based on the TGP to measure production carbon emissions transfer (PCET) in the context of global value chains. Compared with embodied carbon research, the innovative TGP model establishes a traceability mechanism based on the difference between responsibility and actual emissions from the perspective of the value chain, avoiding the endless debate between producer and consumer responsibility, which makes the TGP model more reasonable and fairer. In addition, using long-term input-output data, this study measures spatiotemporal patterns and the network evolution of global PCET. The results show that the total amount of global PCET has increased, and the regions with high outflows of PCET mainly include East Asia, North America, Central and Western Europe, and Russia. Among these regions, the United States and China accounted for the largest proportion of PCET outflow. By contrast, South America and Africa are typical low-outflow regions. From North America via central Europe, Turkey, Iran, South Asia to China, is a “W”-shaped high net outflow belt. The overall concentration of the global PCET network first decreased and then increased, and the network structure evolved into a bipolar network group with China and the United States as the core. Under the shock of the COVID-19 pandemic, the network structure showed a trend towards decentralization. This study suggests that efforts should be made to strengthen the responsibility of major countries, enhance the supervision of lead firms, establish a carbon emission transfer compensation system within value chains, and promote the development and spread of carbon emission reduction technologies to facilitate the reduction of global carbon emissions.

Renewable Energy for Balancing Carbon Emissions and Reducing Carbon Transfer under Global Value Chains: A Way Forward

Research on the relationship between a country’s renewable energy consumption and carbon emissions is of great significance for reducing carbon emissions embodied in international trade. There always exists a gap between production-based and consumption-based carbon emissions. Accordingly, this paper investigates the influence of renewable energy consumption on carbon emission balance, the ratio of production-based emissions to consumption-based emissions, in various countries using the ordinary least square (OLS) method and generalized method of moments (GMM) method. We found that a 1% increase in renewable energy consumption can decrease the carbon emission balance by 5.8%. Furthermore, renewable energy consumption can help narrow the gap between production-based and consumption-based carbon emissions in net emission exporters. In addition, renewable energy consumption can also weaken the negative impact of the global value chains (GVCs) division system on the carbon emission balance. The findings in this study fill the research gap by analyzing the heterogeneous impacts of renewable energy consumption on carbon emission balance embodied within a GVC division system in various countries and provide policy suggestions that renewable energy consumption should be encouraged in net emission exporters to reduce the carbon emission transfers.

Quantifying consumption-based carbon emissions of major economic sectors in Japan considering the global value chain

International trade accelerates the separation between consumption and production on a global scale, thus leading to carbon transfer. Consequently, carbon flow embodied in international trade reallocates global carbon emission responsibilities, consisting of domestic demand and imports but excluding exports. To tackle the geographic flow of emissions embodied in products and services, carbon emissions must be quantified according to the global value chains. Using Japan as a case study, this study tracked the evolution of consumption patterns, international trade, and related carbon emissions based on multi-regional input-output tables, and carbon emissions inventories. Carbon emission transfers among sectors and countries were identified from 2000 to 2014. As a result, imports from the industrial sector led to a gap between production- and consumption-based carbon emissions. Japan was found to be an emissions net import country over the study period, with about 58% of the total carbon emissions inflow coming from China. Moreover, household consumption accounted for nearly 60% of consumption-based emissions, with industrial sector products and services being the primary source of carbon inflow, and the service, transport, and industry sectors are responsible for the majority of domestically released emissions. These conclusions provide valuable information for Japan to customize sectoral carbon reduction priorities, an essential component of setting decarbonization goals from the consumer perspective.

Carbon emission structure decomposition analysis of manufacturing industry from the perspective of input-output subsystem: a case study of China.

In China, manufacturing is the industry that consumes the most energy and emits the most carbon, and the effect of emission reduction on the process of reaching carbon peaking and carbon neutrality is decisive. The existing research on the driving factors of manufacturing carbon emissions has not analyzed the specific structural characteristics of manufacturing carbon emissions from the perspective of industrial relevance, and little attention has been paid to the discussion of carbon emission reduction paths of different manufacturing sectors from the perspective of final demand. This study examines the direct carbon emissions and carbon emissions from final demand in China's manufacturing sector, and decomposes the carbon emissions from final demand into six distinct components using input-output analysis. In addition, this study examines the carbon emission path in manufacturing production activities, as well as the carbon emission reduction potential and scenario prediction of the factors influencing manufacturing carbon emissions. In 2018, the direct carbon emissions and carbon emissions from final demand were approximately 4.61 billion tons and 3.50 billion tons, respectively. Meanwhile, direct and indirect spillovers accounted for 62.1% and 23.1% of carbon emissions from final demand, respectively. Using the carbon emission transfer route map of the manufacturing industry, the direction and amount of carbon emission transfer from various energy sources can be accurately determined. The CR scenario predicts that the manufacturing industry will reach its carbon peak between 2025 and 2030, with a corresponding peak between 4.02 and 4.06 billion tons, and that carbon emissions in 2060 will be 40% lower than in 2018.

Nonlinear Influence of Land-Use Transition on Carbon Emission Transfer: A Threshold Regression Analysis of the Middle Reaches of the Yangtze River in China

Land-use transition (LUT) refers to the change in the land-use form corresponding to the regional economic and social development. At different stages of LUT, changes in the land-use scale and structure may lead to carbon source transfer by affecting industrial transfer and carbon sinks, resulting in changes in the total carbon emission transfer (CET) from the land use in the whole region. The clarification of the relationship between LUT and CET is of great importance for the sustainable development of the regional economy and society and the realization of carbon peak and carbon neutrality. In this paper, we firstly conducted a theoretical analysis of the nonlinear relationship between LUT and CET, then took the Middle Reaches of the Yangtze River in China as an example to explore the characteristics of LUT and CET, and finally constructed a threshold regression model to verify their nonlinear relationship. The following main findings were obtained. (1) From 2000 to 2020, profound LUT had occurred in the Middle Reaches of the Yangtze River, with continuous decreases in farmland, substantial increases in construction land, and a first decrease and then increase in forest land; farmland is the main contributor to construction land and forest with a contribution rate exceeding 60%. (2) During the study period, the CET in the Middle Reaches of the Yangtze River exhibited certain regular characteristics. The phase characteristics of the carbon sink changes follow an intensification–moderation–reintensification–remoderation pattern, and those of the carbon source transfer and net carbon emissions follow an intensification–reintensification–moderation–remoderation pattern. In addition, carbon sink changes are far from enough to offset the effect of carbon source transfer. (3) The nonlinear relationship between LUT and CET was confirmed by the threshold effect at the economic development level, industrial optimization level, and technological progress level. The nonlinear relationship between the LUT and the carbon sink changes in the Middle Reaches of the Yangtze River is on the left side of the U-shaped curve and that between the LUT and the carbon source transfer or net carbon emissions is on the left side of the inverted U-shaped curve.

Legitimacy or efficiency? Carbon emissions transfers under the pressure of environmental law enforcement

Reducing the carbon footprint of companies will be essential if we are to stabilise climate change. However, many researchers are concerned that companies will simply transfer their carbon emissions to another party resulting in carbon leakage rather than emissions reduction. Thus, there is a need to thoroughly investigate what drives companies to transfer carbon emissions as opposed to reducing them. In this study, we explore the motivations and internal mechanisms behind a company's decision to opt for carbon transfers instead of carbon reduction. Drawing on legitimacy theory with a US sample, we provide evidence that strict environmental laws are an external motivation that place pressure on companies to transfer their carbon emissions. Using overseas capital and declared emissions reductions as a proxy for carbon emissions transfer, we find a significant positive correlation to environmental law enforcement. In addition, when facing the force of environmental law, the carbon strategies companies choose are influenced by a felt pressure to operate with both legitimacy and efficiency. Moreover, as pressure mounts in either of these spheres, companies become more and more likely to opt for emissions transfer not emissions reduction. The results indicate that strict environmental regulations forces companies to transfer carbon emissions, which is exacerbated if companies have a high legitimacy and efficiency pressure. As such, this study provides an in-depth discussion on corporate responses to carbon emissions with valuable implications for carbon emissions policymakers.

The structural change and influencing factors of carbon transfer network in global value chains.

Based on the gross trade accounting method and WIOD data, this paper quantifies the global carbon transfer from 2000 to 2014. The social network analysis and temporal exponential random graph model (TERGM) are employed to investigate the structural change and influencing factors of global carbon transfer network from a global value chains (GVCs) perspective. Results show that the deepening of the GVC division connection has enhanced the relations in global carbon transfer network, and the low reciprocity and high disassortativity lie in the difference in GVC division positions among economies. Block model analysis manifests that Plate Ⅱ acts as the engine plate in the network which consists of China and the other four economies. The GVC division connection and relative GVC division position significantly facilitate the formation of carbon emission transfer relations. Moreover, economies' attribute effects and endogenous network structure effects are non-negligible important determinants of network formation.

Assessing the integration effect of inter-regional transmission on variable power generation under renewable energy consumption policy in China

Integrating a high share of variable renewable energy into multi-region power systems is essential and requires an interconnected transmission grid to coordinate regional power system operations. This paper proposes a multi-region power system optimization model to evaluate the role of interconnection in China's power sector for economic benefit, variable renewable energy power generation and allocation, transmission line efficiency and carbon emission transfer in the context of renewable energy consumption policy. The results show that inter-regional power transmission coupled with flexibility technology can facilitate renewable power generation and delivery. The renewable energy consumption policy would intensify this effect, although it leads to a slight drop in economic efficiency. Improving the compatibility of transmission network with variable power is crucial because wind and solar power are expected to make up 60% of the total inter-regional power transmission, particularly the share in the outward transmission lines from the northwest region reaching 91%. Renewable energy integration policy targets in northwest, north, Inner-Mongolia and northeast regions can be improved to 37.5%, 31.5%, 35.3%, and 36.9%, respectively.

Water-carbon nexus relationship and interaction mechanism analysis within Beijing-Tianjin-Hebei urban agglomeration

As the total water resources consumption control and carbon mitigation continuous improvement, the weak water-carbon incorporate management is increasingly exposed. In this study, a water-carbon nexus assessment framework is proposed to analyze the nexus relationship between water consumption and carbon emission, and distinguishes the coupled water-carbon transmission intensity and the transfer paths under regional and industrial scales. According to the practical input-output table, water consumption, and carbon emission information, the framework is applied to Beijing-Tianjin-Hebei urban agglomeration (BTHUA), a population, resource, and trade intensive area of China. Inter-regional/intra-regional water consumption and carbon emission transfer fluxes between sectors, the pairwise ecological relationship, and the water-carbon nexus were analyzed. Results indicated that the water-carbon transfer indexes from Hebei to Beijing and Tianjin were 161.85 kg/m3 and 113.88 kg/m3 in the study period, along with the most water consumption and carbon emission, and the worst water-carbon nexus. From the industrial perspective, electricity and gas supplying industry provided 7.8% and 29.1% of the total carbon transfer in Tianjin and Hebei, as the most key node sectors on the water-carbon nexus in the BTHUA. The research provides valuably supporting the adjustment of the existing urban agglomeration water-carbon nexus management schemes.

Interregional polarized and trickling-down effect of carbon emission space and the optimization policies: Case studies of the Jing-Jin-Ji region

Research has shown that there is huge amount of transfer of carbon emissions embodied in trade (CEs-ET) between developed and underdeveloped regions, which causes equity and efficiency losses in carbon emission (CE) reduction. The exploration of effective approaches to mitigate CEs-ET transfer and promote CE reduction has become worldwide hot but difficult issues. This research innovatively introduced the polarized and trickling-down effect in development economics and the environmental externality theory in environmental economics into the study of CEs-ET transfer, and demonstrated that the net CEs-ET inflow to developed regions from underdeveloped regions is actually the polarized effect of “carbon emission space (CES)” of developed regions on underdeveloped regions caused by regional economic development gaps. To reduce CEs-ET transfer and promote the overall CE reduction, it is required to formulate regional collaboratively implemented environmental-economic policies from the perspective of increasing interregional cooperation, to reduce the CES-polarized effect and improve the CES-trickling-down effect. Next, we chose the typical and representative region in study of CEs-ET transfer, the Jing-Jin-Ji region, as case studies, to illustrate the CES-polarized and CES-trickling-down effects based on the latest 2002–2017 interregional input-output (I–O) data. By applying the models of emissions embodied in bilateral trade (EEBT) and structural decomposition analysis (SDA), we evaluated the evolution of the CES-polarized effects in the Jing-Jin-Ji region and their driving mechanism. We found that Beijing and Tianjin had an obvious CES-polarized effect on Hebei, the Beijing-Hebei and Tianjin-Hebei CES-polarized effect firstly strengthened and then weakened, and was highly concentrated in a few industries such as electricity steam and hot water production and supply (ElectpowerProd), metals smelting and processing (MetalSmelt), and Coal mining and processing (Coalmin). Scale and technology were the key driving factors, but for different industries, scale and technology functioned differently. The trickling down of technology and scale in the Jing-Jin-Ji region produced a CES-trickling-down effect and restricted further aggravation of the CES-polarized effect. Subsequently, we established a coupling relationship (CR) model, which comprehensively compared the economic and environmental effects of adjusting the trade value of an industry. Finally, by combining the industrial CES-polarized effect, the SDA results, and the CR results, we identified the key regulating industries and put forward the Beijing-Hebei, Tianjin-Hebei, and the Jing-Jin-Ji collaboratively implemented optimization policies, to reduce the CES-polarized effect, improve the CES-trickling-down effect, and promote the collaborative CE reduction in the Jing-Jin-Ji region. This research could enrich the theoretical connotation and driving mechanism analysis of the formation and evolution of CEs-ET transfer, and provide a new reference for the formulation of an effective and cost-effective regional collaboratively implemented CE reduction scheme between developed and underdeveloped regions.

Carbon footprint and embodied carbon emission transfer network obtained using the multi–regional input–output model and social network analysis method: A case of the Hanjiang River basin, China

China is the largest carbon emitter in the world; thus, reducing carbon emissions while maintaining economic growth has become an important issue. Within the context of carbon neutrality strategies, calculation of the carbon footprint and embodied carbon transfer can help policymakers formulate reasonable carbon reduction plans. The multi–regional input–output (MRIO) model can clarify carbon flow pathways between regions, and social network analysis (SNA) can comprehensively evaluate the different positions of individual sectors. Combining these two approaches, the specific characteristics of carbon emissions in complex production and trade relationships can be analyzed. China has become the world’s top total carbon emitter, and the Hanjiang River basin (HJRB) constitutes an important economic link between the developed and less developed regions of China. Studying carbon emissions in the HJRB can provide a reference for other, similar regions and is vital for the realization of China’s carbon emission reduction targets. This paper examines the carbon footprint and embodied carbon emission transfer among three provinces and 12 sectors in the HJRB during different periods and identifies the key industries in the carbon transfer process. The results indicate that (1) the total carbon footprint in the HJRB exhibits an increasing trend. Energy-based Shaanxi Province exhibits the highest growth rate of the carbon footprint, agriculture-based Henan Province shows a decreasing trend, and consumption-based Hubei Province displays the lowest carbon footprint intensity. (2) There are differences in the carbon emission coefficient and final consumption rate among various sectors; construction, metal processing and metal and non-metallic products, processing and manufacturing of petroleum, coking, nuclear fuel, chemical products, and other services are the sectors accounting for a high proportion of emissions. (3) The more obvious the supply relationship is, the higher the flow of embodied carbon emission transfer between sectors. (4) Energy-based regions transfer large amounts of fossil energy, electricity, steel and coal resources to developed regions and simultaneously assume more of the carbon reduction pressure imposed on developed regions. (5) The key industries within the embodied carbon emission transfer network notably control the carbon emissions of other industries and can provide breakthroughs to achieve challenging carbon emission reduction targets.

WITHDRAWN: Effects of government regulations on under-reporting of carbon emission transfers by enterprises in supply chains

This article has been withdrawn at the request of the authors. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal

Effects of Government Regulations on Under-Reporting of Carbon Emission Transfers by Enterprises in Supply Chains

In low-carbon environments, asymmetric carbon information causes the enterprises in a supply chain to face the risk of misstatements about carbon emissions. Such misstatements could affect the decisions about carbon emission transfers in the supply chain. To optimize carbon emission transfers among supply chain enterprises, this study formulates a supplier-led Stackelberg game model incorporating the government’s initial carbon emission allowances and fines. The study also examines the mechanism of the behaviors of enterprises in low-carbon supply chains, the proportions of initial quotas, the impact of government fines on carbon transfers, and the influence of the supply chain and carbon emission transfers on related supply chain decisions and profits. The main findings are as follows. First, the proportion of the government’s initial quota has a positive effect on the carbon emission transfer quantity of the supplier, while government fines and misstatement factors have a negative effect. Second, the carbon emissions of the unit product of the supplier decrease as the under-reporting factor and carbon emission transfer quantity of the supplier increase. The under-reporting factor has a stronger effect on the carbon emissions of the unit product. Third, in a carbon-free market, carbon emission transfers negatively affect the disclosed profits of the supply chain, whereas in a perfect carbon market, the carbon trading price has a certain endogenous regulation mechanism for the suppliers’ operational decisions. Fourth, the supplier’s wholesale price order quantity is negatively correlated with the supplier’s carbon emission transfer quantity, but positively correlated with the initial carbon quota ratio.

Correction to: Complex network analysis of carbon emission transfers under global value chains

Correction to: Complex network analysis of carbon emission transfers under global value chains

ONE BELT, ONE ROAD, SUSTAINABLE DEVELOPMENT, REGIONAL CARBON MARKET, RISK INDICATOR SYSTEM, FROM THE PSYCHOLOGICAL PERSPECTIVE OF EMOTIONAL BEHAVIOR CHANGE

ONE BELT, ONE ROAD, SUSTAINABLE DEVELOPMENT, REGIONAL CARBON MARKET, RISK INDICATOR SYSTEM, FROM THE PSYCHOLOGICAL PERSPECTIVE OF EMOTIONAL BEHAVIOR CHANGE

Spatial-Temporal Evolution Analysis of Carbon Emissions Embodied in Inter-Provincial Trade in China.

Under the support of Multi-Regional Input–Output (MRIO) analysis, this study constructs the Embodied Carbon Emission Transfer Network (ECETN) using the input–output tables of 42 sectors in 31 provinces of China in 2012, 2015, and 2017 and applies a series of complex network measurement indicators and analysis methods to describe its evolution features. The results show that the embodied carbon emission transfers between provinces generally narrow over time. With its high clustering coefficient and short average path length, ECETN has small-world characteristics and behaves sensitively, and changes in individual provinces can quickly spread and affect the entire system. In addition, the clustering effect and the spatial spillover structural properties of ECETN are explored based on the block model analysis. Finally, Quadratic Assignment Procedure (QAP) is used to analyze and quantify the contribution of provincial structural roles to ECETN, and it is found that spatial adjacency and differences in strength-in, strength-out, and betweenness centrality have significant positive effects, while differences in eigenvector centrality, clustering coefficient have significant negative effects. The restructuring of domestic trade can help achieve national emission reduction. These findings can provide more insights for the government to formulate future development directions and policies to reduce emissions further.

Decomposition of China's regional carbon emission paths: an analysis of environmental input and output considering regional development differences.

At present, the imbalance in regional development and carbon emissions are the two major challenges that China faces in terms of achieving high-quality development. This paper takes regional development differences as the starting point. First, we adopt the improved CRITIC method to measure the comprehensive development level of 30 regions in China and use K-means clustering to divide the 30 regions into five development levels. Second, the structural path analysis for environmental input-output analysis (EIOA-SPA) model is used to quantify the transfer of carbon emissions between sectors in various regions. Finally, a comprehensive analysis is performed based on the development characteristics of each region and the decomposition results of the carbon emission paths. Then, more precise carbon emission reduction strategies are proposed for the development of different regions in China. The results show that first, the development gap between regions in China has improved, and the development of the central and western regions has achieved remarkable results. However, differences between the north and the south and the gap between coastal and inland regions still exist. Second, the direct carbon emissions of regions with different levels of development are mainly derived from high energy-consuming sectors, especially the production and supply of electricity and heat sector. Third, there are certain differences in the indirect carbon emission pathways of regions with different development levels. The transportation, storage, and postal sector in high developed regions have obvious driving effects on carbon emissions. The building sector plays a prominent role in driving carbon emissions in high developed regions and medium-high developed regions. The building sector, nonmetallic mineral products sector, metal smelting sector, and rolled processed product sector in medium developed regions and medium-low developed regions have relatively high carbon emission-stimulating effects. Therefore, it is necessary to adopt differentiated emission reduction strategies for regions with different development levels in China to achieve adequate carbon emission reductions. This effort would further promote the construction of China's ecological civilization.

Carbon Transfer Decision Model Based on LMDI Method.

Establishing a coordinated governance mechanism for regional carbon emissions is an essential way to achieve carbon peak and carbon neutrality, while the study of interprovincial carbon emissions transfer is one of the important foundations of regional carbon emissions coordinated governance research. Based on the multiregional input-output (MRIO) model, this study calculated the carbon emissions from both the producers' perspective and the consumers' perspective and analyzed the interprovincial net carbon emissions transfer decision. Furthermore, the logarithmic mean Divisia index (LMDI) method was adopted to decompose the factors that affect the province's net carbon emissions into technological effect, structural effect, input-output effect, and scale effect. It was revealed that the input-output effect was the primary influencing factor of the net carbon transfer at the provincial level.