Study on the CO<Subscript>2</Subscript> emissions embodied in the trade of China’s steel industry: based on the input–output model

The impact of trade on the environment and the climate has become a focus of attention. Tending to develop industries with higher added values, developed countries rely on importing high energy consumption goods from developing countries, and however, some CO₂ emissions are embodied in the process of import. Currently, the accounting method of the territorial responsibility used to get the international data of greenhouse gas inventories ignores the difference between domestic consumption and export demands. Thus, developing countries bear the responsibility of pollution emissions from the export. The steel industry is an important basic industry of China’s national economy as well as a vital part in the industrial system. With the expansion of trade scale, the impact of the export and import of China’s steel on CO₂ emissions is growing. This paper studied the embodied CO₂ emissions in the trade of China’s steel from 2005 to 2014, using the input–output model and the trade data of the China’s steel imports and exports. The results indicate that (1) the complete CO₂ emissions of China’s steel industry are high. (2) The increase in the export scale makes the embodied CO₂ emissions in the trade of China’s steel export increase, and (3) China is a net exporter of CO₂ emissions in the steel trade. Especially after 2007, the value of China’s steel exports has been larger than that of China’s steel imports, so China had borne much CO₂ emissions responsibility in the trade of China’s steel. Therefore, this paper puts forward that, in the future, the export structure of goods should be optimized into the high-tech products with the high added value, low energy consumption and low carbon emissions, and meanwhile, service industry is promoted to improve technical support to reduce CO₂ emissions in the steel industry.     

Real-world emissions of gasoline passenger cars in Macao and their correlation with driving conditions

Using a portable emissions measurement system, 16 gasoline passenger cars were tested on a fixed route consisting of different types of roads in Macao and the data were normalized with the vehicle-specific power bin method. The normalized HC, CO and NO _X emission levels of the seven passenger car samples with model year older than 2000 were 3.19 ± 5.04, 14.59 ± 22.88, 2.57 ± 2.12 g/km, respectively. The HC, CO and NO _X emission levels of other newer samples were 0.02 ± 0.02, 0.23 ± 0.29 and 0.10 ± 0.13 g/km, respectively. The scrappage of old passenger cars in Macao should be a high priority to control the total emissions of motor vehicles. Based on relative emission levels, a clear and similar pattern for gaseous pollutants and fuel consumption with driving conditions was identified. The emissions of HC, CO and NO _X are best fitted to average speed with inverse functions. Fuel consumption is best fitted to average speed with a power function. Compared to the average driving conditions, the emission factors of HC, CO and NO _X and fuel consumption of gasoline passenger cars during the rush hours on the Macau Peninsula will be increased by 61, 55, 45 and 90 %, respectively. This situation will deteriorate by 2015 if no further transportation management strategies are implemented in Macao. To save energy and mitigate the air pollutant emissions in the urban area, improved traffic planning and travel demand management are also necessary.     

Assessment of the impact of biogenic VOC emissions in a high ozone episode via integrated remote sensing and the CMAQ model

In many metropolitan regions, natural sources contribute a substantial fraction of volatile organic compound (VOC) emissions. These biogenic VOC emissions are precursors to tropospheric Ozone (O₃) formation. Because forests make up 59% of the land area in Taiwan Province, China, the biogenic VOC emissions from forests and farmland could play an important role in photochemical reactions. On the other hand, anthropogenic emissions might also be one of the major inputs for ground level O₃ concentrations. Hence, emission inventory data, grouped as point, area, mobile and biogenic VOC sources, are a composite of reported and estimated pollutant emission information and are used by many air quality models to simulate ground level O₃ concentrations. Before using relevant air quality models, the emission inventory data generally require huge amounts of processing for spatial, temporal, and species congruence with respect to the associated air quality modeling work. The fist part of this research applied satellite remote sensing and geographic information system (GIS) analyses to characterize land use/land cover (LULC) patterns, integrating various sources of anthropogenic emissions and biogenic emissions associated with a variety of plant species. To investigate the significance of biogenic VOC emissions on ozone formation, meteorological and air quality modeling were then employed to generate hourly ozone estimates for a case study of a high ozone episode in southern Taiwan, which is the leading industrial hub on the island. To enhance the modeling accuracy, a unique software module, SMOKE, was set up for emission processing to prepare emission inputs for the U.S. EPA’s Models-3/CMAQ. An emission inventory of Taiwan, TEDS 4.2, was used as the anthropogenic emission inventory. Biogenic emission modeling was accomplished by BEIS-2 in SMOKE, with improvement of local LULC data and revised emission factors. Research findings show that the majority of biogenic VOC emissions occur in the mountainous areas and farmlands. However, the modeling outputs show that downwind of the most heavily populated and industrialized areas, these biogenic VOC emissions have less impact on air quality than do anthropogenic emissions.     

Stress of urban energy consumption on air environment

With rapid urbanization and heavy industrialization as well as the rapid increase of cars in China, the effect of energy consumption on urban air environment is increasingly becoming serious, and has become a hot topic for both scholars and decision-makers. This paper explores the effect mechanism and regulation of urban energy consumption on the air environment, and summarizes the framework of the stress effect relationship and the evolutionary process. In accordance with the effect relationship of the internal factors between the two, analytic approaches studying the stress effect of urban energy consumption on air environment are proposed, including the analysis of air environment effects caused by urban energy consumption structure change, and the analysis of air environment effects caused by urban energy economic efficiency change, as well as a decomposition analysis of air pollutant emission caused by urban energy consumption. Applying the above-mentioned approaches into a case study on Beijing City, this paper analyzes the effect relationship among urban energy consumption structure improvement, energy economic efficiency increase and air quality change since the period when Beijing City officially proposed to bid for the 2008 Olympic Games in 1998. In addition, it further analyzes the effect and contribution of urban industrial activity level, industrial economic structure, industrial energy intensity, and industrial energy structure as well as emission coefficients on the change in industrial SO₂ emission, which can provide valuable information to the government for making comprehensive environmental policies, with the use of the logarithmic mean Divisia index (LMDI) method. It is shown that under the precondition that the industrial economy maintain a continuous and rapid increase, improvements in energy intensity and a decline in emission coefficients are the main means for reducing Beijing’s industrial SO₂ emissions.     

个人终端消费导向的碳足迹研究框架——支撑我国环境外交的碳排放研究新思路

碳足迹揭示了终端消费领域人类活动对于全球气候变化的影响,是碳排放研究从生产层面转向消费层面的重要标志。开展碳足迹研究可以揭示人类终端消费活动导致的碳排放以及消费能力、消费结构与碳足迹的关系,并最终服务于我国的环境外交。在分析传统生产层面碳排放研究、总结碳足迹研究最新进展的基础上,从气候变化研究领域中就人类活动进行研究的3大核心命题——“规律、权益、策略”出发,提出了碳足迹研究的基本理念、基本假设和基本判断,总结了相应的原则。最后,对生存型、发展型和奢侈型消费及相应碳排放进行了初步的判断和核算。     

Assessing the synergistic reduction effects of different energy environmental taxes: the case of China

Imposing any tax among carbon tax, sulfur tax and nitrogen tax on fossil fuels will also reduce the other two air pollutants. Neglecting the synergistic effect of each energy environmental tax and levying carbon tax, sulfur tax and nitrogen tax at the same time will overestimate the abatement cost of air emissions. This study adopts a partial equilibrium model which uses linear demand and supply curves to illustrate the emission reductions in carbon tax, sulfur tax and nitrogen tax. The synergistic reduction effects of CO₂, SO₂ and NO _x are firstly evaluated under the implicit tax scenario of resource tax and consumption tax on fossil fuels. Then it is compared with the synergistic reduction effects of CO₂, SO₂ and NO _x under different explicit tax scenarios of increasing tax rate on carbon tax, sulfur tax and nitrogen tax. If the synergistic reduction effect of explicit environmental taxes is better, this research aims to find one kind of environmental tax among carbon tax, sulfur tax and nitrogen tax with the best synergistic reduction effect and to provide a decision support for the policy makers of energy environmental taxes. The results indicate that explicit environmental taxes have better synergistic reduction effects compared with the current implicit environmental taxes. And explicit sulfur tax can lead to the largest synergistic reduction effects of CO₂, SO₂ and NO _x . Therefore, the policy makers of energy environmental taxes could consider adopting the explicit sulfur tax to reduce various environmental air emissions at the largest amount.     

Multi-peril risk assessment for business downtime of industrial facilities

The chemical industry is one of the most important industry sectors in terms of energy consumption and CO₂ emissions in China. However, few studies have undertaken accounting of the CO₂ emissions in the chemical industry. In addition, there are some shortcomings in the traditional accounting method as a result of poor data availability, such as the incomplete consideration of emission sources and overestimation of actual emissions. Based on the traditional accounting method and the actual situation of the chemical industry, this study proposes a method called the Emission Accounting Model in the Chemical Industry, which covers fossil energy-related emission, indirect emission generated by electricity and heat, carbonate-related process emission and the reuse of CO₂. In particular, fossil energy used as feedstock is included. By applying the Emission Accounting Model in the Chemical Industry in China, the calculated CO₂ emissions would be 19–30% less than the result from the traditional method. In addition, it is found that the indirect CO₂ emissions generated by electricity and heat account for 67% of the total amount, the fossil energy-related emissions account for approximately 37%, the process-related emissions accounted for 2%, and reuse of CO₂ accounts for ??6% in 2016. The production of ammonia, ethylene and calcium carbide generated approximately half of the total CO₂ emissions in 2016. In addition, in view of emission sources and carbon source flow, two other bottom-up accounting methods are proposed that can take effect when the chemical plant-level data are available.

     

The quantification of atmospheric emissions from complex configuration sources using reverse dispersion modelling

Reverse dispersion modelling was employed to quantify sulphur dioxide (SO₂) and nitrogen dioxide (NO₂) emissions from brick firing clamp kilns and spontaneous combustion from a coal discard dump. Reverse dispersion modelling technique integrates ambient monitoring and dispersion simulation to calculate actual emission rates from an assumed rate of 1 g per second (g/s). Emission rates and emission factors were successfully quantified for SO₂, but not for NO₂, due to the influence of external sources and the complexity regarding the varying proportion of nitrogen oxides released from the kiln. Quantified emission factor for clamp kiln firing ranged from 1.91–3.24 g of SO₂ per brick fired and 0.67–1.14 g of SO₂ per kilogram of bricks fired. The variation in SO₂ emission factors was linked to high variability in energy input. The source configuration input to the dispersion model, assumed to represent the kiln, was changed from a volume source to a more effective “bi-point” source situated at the top of the kiln, with buoyancy calculated from the carbon combustion rate. In addition, SO₂ emission rate for spontaneous combustion from the discard dump was quantified as 0.35 g/s. 274 tons of discard material was estimated to burn annually, assuming that the emission rate is consistent over a year. Consequently, the reverse dispersion modelling and the elevated “bi-point” source technique may be considered a novel approach for quantifying emissions from combustion of materials or mixture of materials where knowledge of source parameters is limited.     

Forecasting hourly particulate matter concentrations based on the advanced multivariate methods

In this study, several multivariate methods were used for forecasting hourly PM₁₀ concentrations at four locations based on SO₂ and meteorological data from the previous period. According to the results, boosted decision trees and multi-layer perceptrons yielded the best predictions. The forecasting performances were similar for all examined locations, despite the additional PM₁₀ spatio-temporal analysis showed that the sites were affected by different emission sources, topographic and microclimatic conditions. The best prediction of PM₁₀ concentrations was obtained for industrial sites, probably due to the simplicity and regularity of dominant pollutant emissions on a daily basis. Conversely, somewhat weaker forecast accuracy was achieved at urban canyon avenue, which can be attributed to the specific urban morphology and most diverse emission sources. In conclusion to this, the integration of advanced multivariate methods in air quality forecasting systems could enhance accuracy and provide the basis for efficient decision-making in environmental regulatory management.     

Investigating the sensitivity factors of household indirect CO<Subscript>2</Subscript> emission from the production side

Indirect emission from household consumption, which is affected by technologies of production sectors, is the significant contributor to national CO₂ emission. Input–output model is preferred when direct and indirect transactions and emissions are considered simultaneously. Based on input–output model, this study applies the sensitivity analysis to indirect emission from rural and urban domestic consumption, respectively. It allows us to investigate the influences of the technology change both at the transaction level and at the sector level. In addition, multi-years symmetrical input–output tables are adopted to obtain dynamic analysis in order to study the variation trend of the influences. At the transaction level, the technology change of production and supply of electric power and heat power self-supplied intermediate inputs exerts the most significant influence on indirect emission from both rural and urban consumption. At the sector level, indirect emissions from rural and urban consumption are both the most sensitive to the technology change of chemistry industry. Furthermore, there are more key transactions selected under consideration of rural domestic consumption compared with the urban. Additionally, the influencing degree and variation trends of the same technology change would be different between rural and urban situation. According to the above findings, policy recommendations aiming at achieving emission abatement from household consumption are provided in detail.     

The impact of inter-industry R&amp;D technology spillover on carbon emission in China

Based on input–output table to measure inter-industry R&D technology spillover, this paper introduces inter-industry R&D technology spillover into panel econometric model for carbon dioxide (CO₂) emissions factor analysis. Using the panel data of 34 industrial sectors in China from 2005 to 2014, the results reveal that there is an inverted “U-shaped” nonlinear relationship between R&D technology spillover (intensity) and carbon emission; it is estimated that R&D technology spillover can reduce carbon emission currently; the indirect impact of R&D technology spillovers or spillovers intensity through R&D intensity on carbon emissions is also beneficial to carbon emission reduction; at last, this study suggests that industrial sectors should improve R&D intensity and strengthen technical exchanges and cooperation with other related sectors for the purpose of R&D technology spillover increase and CO₂ emissions reduction.     

Research on China export structure adjustment: an embodied carbon perspective

This paper calculated the embodied carbon in China export and its distribution in each industrial sector. The calculation results showed the total carbon emission of export experienced an increase before 2007 and then a decrease till 2010. The ratio of export embodied carbon accounting for the total carbon emission in China also increased from 31 % in 2002 to 52 % in 2007 and then declined to 40 % in 2010. As for distribution, the export embodied carbon emission of the following industries such as machinery and equipment manufacturing, metal products manufacturing industry, chemical industry, textile, clothing and leather products manufacturing industry ranked the highest. According to the calculation and analysis of the main driving factors of embodied carbon growth, we analyzed the structure effect, scale effect and technological effect’s influence on embodied carbon growth, respectively. We also calculated the trade competitiveness index of 17 export industries. Through research, we found that the products with strong international competitiveness belong to high-carbon-emission categories, which was the main reason of high carbon emission in China export. Finally, we proposed related policy suggestions to promote China’s export trade structural readjustment and optimization and China’s low carbon development in export.

     

Serviceability-related reliability for mainshock-damaged reinforced concrete piers considering the aftershock-induced seismic hazards

To investigate the impact of carbon emission reduction paths on energy demand and CO₂ emissions in China, in this study, quantitative carbon emission reduction paths in the period 2014–2020 are established by decomposing the target for emissions reduction. An optimization model of energy demand, into which reduction paths are incorporated, is then constructed from a goal-oriented perspective. The results suggest that energy consumption varies under different emission reduction paths. Coal demand is found to be much more sensitive to the choice of emission reduction path than other forms of energy; in particular, it responds strongly to the decreasing reduction path. We conclude that the decreasing reduction path is a better means than the increasing reduction path of achieving China’s emission reduction target for 2020 with the least amount of energy and the least amount of CO₂ emissions.     

The impact of energy consumption on environment and public health in China

Fossil energy consumption is one of the main reasons for the deterioration of environmental pollution and decline in public health. This paper tests for the long-run and short-run relationship among energy consumption, environment pollution and public health using the autoregressive-distributed lag approach in China for the period 1985–2014. The study used energy consumption variables (i.e., the proportion of coal consumption, that of oil and clean energy, abbreviated as PCC, POIL and PCE, respectively), environmental pollution ones (i.e., SO₂ emissions, abbreviated SO₂, soot and dust emissions,), two health proxies (i.e., the proportion of cardiovascular and respiratory diseases mortality, abbreviated as PCD and PRD, respectively). These variables were selected due to vital importance in China. The overall results indicate that there was co-integration relationship under the study with statistically significantly positive relationship between environmental pollution and energy consumption, public health and environmental pollution in the short and long run. Comparing the long-run and short-run coefficients of energy use variable with respect to SO₂ and soot indicates that the long-run coefficients are the same as the short-run. The long-run coefficients of soot and dust emissions with respect to PCD and PRD, respectively, are higher than the short-run coefficients. This implies that environment pollution level is found to worsen with respect to fossil energy use presently and over time, while public health level descending with reference to soot and dust emission over time in China. The Granger causality results suggested a unidirectional Granger causality between energy use and environment pollution, environment pollution and public health. The results emphasized the importance of energy transformation and sustainable development policies that help to adjust the structure of energy consumption and to improve public health level.     

Industrial sources of CO2 emissions in Poland in the light of underground storage possibilities

Industrial sectors responsible for large part of CO₂ emissions in Poland are characterized from the point of view of possibilities of sequestration of this gas by underground storage. On the basis of official statistics and data obtained from local administration and individual plants, attempt was made to evaluate the magnitude of emissions from selected categories, sub-categories and sectors of the industry (in accordance with methodology of IPCC), concentration of CO₂ in combustion gases and those emitted by industry, and to identify major point sources of emission of this gas in Poland. A special attention was paid to those sectors of industry that may be the first to act as a source of carbon dioxide for sequestration by underground storage in the nearest future. To cite this article: R. Tarkowski, C. R. Geoscience 337 (2005).     

Black carbon and organic carbon emissions from wildfires in Mexico

In Mexico, approximately 7650 wildfires occur annually, affecting 263 115 hectares of land. In addition to their impact on land degradation, wildfires cause deforestation, damage to ecosystems and promote land use change; apart from being the source of emissions of toxic substances to the environment (i.e., hydrogen cyanide, black carbon and organic carbon). Black carbon is a short-lived greenhouse pollutant that also promotes snow and ice melting and decreased rainfall; it has an estimated global warming potential close to 5000.¹ We present an estimate of the black carbon and organic carbon emissions from wildfires in Mexico from 2000 to 2012 using selected emission factors from the literature and activity data from local agencies. The results show average emissions of 5955 Mg/yr for black carbon and 62 085 Mg/yr for organic carbon. Black carbon emissions are estimated to be 14 888 Gg CO₂ equivalent (CO₂ eq) per year on average. With proper management of wildfires, such emissions can be mitigated. Moreover, improved air quality, conservation of ecosystems, improvement of visibility and maintenance of land use are a subset of the related co-benefits. Mitigating forest organic carbon emissions, which are ten times higher than black carbon emissions, would also prevent the morbidity and mortality impacts of toxic organic compounds in the environment.     

Tracking volcanic sulfur dioxide clouds for aviation hazard mitigation

Satellite measurements of volcanic sulfur dioxide (SO₂) emissions can provide critical information for aviation hazard mitigation, particularly when ash detection techniques fail. Recent developments in space-based SO₂ monitoring are discussed, focusing on daily, global ultraviolet (UV) measurements by the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite. OMI’s high sensitivity to SO₂ permits long-range tracking of volcanic clouds in the upper troposphere and lower stratosphere (UTLS) and accurate mapping of their perimeters to facilitate avoidance. Examples from 2006 to 2007 include eruptions of Soufriere Hills (Montserrat), Rabaul (Papua New Guinea), Nyamuragira (DR Congo), and Jebel at Tair (Yemen). A tendency for some volcanic clouds to occupy the jet stream suggests an increased threat to aircraft that exploit this phenomenon. Synergy between NASA A-Train sensors such as OMI and the Atmospheric Infrared Sounder (AIRS) on the Aqua satellite can provide critical information on volcanic cloud altitude. OMI and AIRS SO₂ data products are being produced in near real-time for distribution to Volcanic Ash Advisory Centers (VAACs) via a NOAA website. Operational issues arising from these improved SO₂ measurements include the reliability of SO₂ as proxy for co-erupted ash, the duration of VAAC advisories for long-lived volcanic clouds, and the potential effects of elevated concentrations of SO₂ and sulfate aerosol in ash-poor clouds on aircraft and avionics (including cumulative effects after multiple inadvertent transits through dilute clouds). Further research is required in these areas. Aviation community assistance is sought through continued reporting of sulfurous odors or other indications of diffuse volcanic cloud encounters, in order to validate the satellite retrievals.     

Chemistry and sulfur isotopic composition of precipitation at Bologna, Italy

Individual and monthly precipitation samples from the polluted atmosphere of Bologna (Emilia-Romagna province) were collected during March 1996 to May 1997 and analyzed for major ions in solution and S isotopes in dissolved SO₄.Weighted mean enrichment factors relative to seawater are found to be 1.0 for Na, 15.2 for K, 105 for Ca, 3.3 for Mg, 17.3 for SO₄ and 663 for HCO⁻₃. Very good positive correlations are observed for the Ca²⁺–Mg²⁺–HCO⁻₃–SO²⁻₄–NO⁻₃ system, indicating that dissolution of Ca (±Mg)-carbonate particles by H₂SO₄ and HNO₃ from combustion of oil and gas is a major process controlling the chemical composition of rain and snow. Na⁺ and Cl⁻ in monthly precipitation derive essentially from sea spray, but the contribution of Na⁺ from continental sources is appreciable in a number of individual rains. NH⁺₄ appears to be on average more abundant in spring and summer precipitation, its main sources being microbial activity in soils and application of fertilizers. K⁺ is probably of continental origin from soil dust.The S isotopic composition of SO₄ is systematically positive, with mean δ³⁴S values of +3.2±1.6‰ (n=40) in individual precipitation and +2.8±1.4‰ (n=12) in monthly precipitation. These isotopic compositions are interpreted in terms of a dominant contribution of S from anthropogenic emissions and subordinate contributions from biogenic and marine sources. Pollutant SO₄ is estimated to have a δ³⁴S value in the range +2.5 to +4.5‰, whereas a distinctive δ³⁴S of −4.5‰ or lower indicates SO₄ from oxidation of biogenic gases.The isotopic and chemical compositions of SO₄ do not depend on wind direction, thus testifying to a mostly local source for pollutant S in the Bologna atmosphere.     

Impact of household expenditures on CO2 emissions in China: Income-determined or lifestyle-driven?

The aim of this paper is to analyze the relationship between household expenditure and CO₂ emissions among different income groups of urban and rural households in China. Having employed the 2007 Social Accounting Matrix of China, this study examines the direct and indirect CO₂ emissions caused by household demand. The results show that within both urban and rural households, the higher the income level is, the higher the per capita emissions are; the CO₂ emissions per unit expenditure due to savings and taxes are generally much larger than those from consumption of goods and services; and these emissions per unit consumption expenditures mainly come from indirect emissions. To deeply explore the relationships between consumption patterns and CO₂ emissions, two scenarios are established to eliminate the differences in income level and consumption propensity among different groups step by step. Main results indicate that (1) the income gap is the primary cause of the significant differences in emission levels among each group; (2) the difference in consumption propensity is also a notable reason; and (3) the rural higher income groups spend a larger share of their income on those carbon-intensive goods (e.g., electricity, transportation, energy products), thus making their consumption patterns more carbon-intensive, while for the urban, the consumption patterns of lower income groups are more carbon-intensive. Finally, policy recommendations on the reduction of household emissions are also made.

     

Driving forces of indirect carbon emissions from household consumption in China: an input–output decomposition analysis

Human activities have become a major source of Earth’s climate change, which brings the rise of surface air temperature and subsurface ocean temperature. Therefore, promoting sustainable consumption and production patterns is imperative to minimize the use of natural resources and reduce emissions of pollutants. This study uses Economic Input–Output Life-Cycle Assessment method and structural decomposition model to identify the driving forces that influence the changes in carbon emissions from China’s residential consumption in the context of sustainable consumption. The findings of the study are as follows: (1) indirect carbon emissions from Chinese household consumption increase rapidly over time; (2) the largest carbon dioxide emitting sector turns from agriculture sector in 1992 into service sector in 2007; (3) the consumption level and the emission intensity are the main drivers that influence the change in indirect carbon emissions; and (4) the factor of consumption level presents positive effect on the emissions, while the emission intensity effect plays a negative role. Besides, the factors of urbanization, production structure, population size and consumption structure also promote the rapid increase in carbon emissions.