Greenhouse Gases In China Research Articles

Greenhouse gas emissions embedded in US-China fuel ethanol trade: A comparative well-to-wheel estimate

Abstract The US-China biofuel trade has experienced exponential growth in the past few years. This study conducts life cycle analysis on the US-China fuel ethanol trade and compares the greenhouse gas (GHG) emissions from ethanol produced in China with ethanol imported from the U.S. We conduct lifecycle analysis for five China ethanol production pathways – corn, cassava, sweet sorghum, corn stover, and corncob, using the GREET (Greenhouse gases, Regulated Emissions and Energy use in Transportation) model. The well-to-pump (WTP) GHG emissions are estimated to be 54–234 gCO 2e /MJ. The WTP emissions of ethanol imported from the U.S. are lower than starch- and sugar-based ethanol in China. By building vehicle pathways for passenger cars in China, we estimate the well-to-wheel emissions to be 184–253 gCO 2e /km for spark-ignition (SI) engine vehicles. Overall, importing ethanol from the U.S. is estimated to reduce emissions by 34.21 gCO 2e /MJ on average, suggesting great potential of imported ethanol on curbing China's GHG emissions.

Challenges to addressing non-CO2 greenhouse gases in China’s long-term climate strategy

ABSTRACTUnder the Paris Agreement, countries are encouraged to submit long-term low greenhouse gas emissions development strategies. Such strategies will merge emissions goals with socio-economic objectives and enable countries to increase their ambition over time, thus offering an opportunity to close the gap between the current emissions trajectory and the Agreement’s ‘well below 2°C’ target. China is in the process of preparing its own long-term strategy. We argue in this article that non-CO2 greenhouse gases (NCGGs) should be an essential component of China’s long-term low-emissions strategy. To incorporate NCGGs into China’s long-term low-emissions development strategy, key scientific and institutional challenges should be addressed, such as uncertainty about the accuracy of NCGG emissions inventories; uncertainty about future projections of NCGG emissions; and institutional coordination deficits and imbalanced policy approaches. Overcoming these barriers will have significant implications for climate change mitigation and can open a path for the development of concrete follow-up actions.Key policy insightsNon-CO2 greenhouse gases (NCGGs) make up around 17% of China’s GHG emissions, but China has no quantified target to limit or reduce these gases.NCGG emissions mitigation should be an essential component of China's long-term low-emissions strategy, which is currently under development.Considerable uncertainty exists over both historical NCGG emissions data and forecasts. This poses challenges to developing a comprehensive multi-gas strategy.Institutional challenges must also be addressed, such as fragmentation of responsibility for NCGGs.

Estimation of greenhouse gas emissions in China 1990–2013

AbstractConsidering the little attention given to building China's greenhouse gas (GHG) emission inventories, a long timescale and detailed GHG inventory is presented based on the latest released official statistical data in China from 1990 to 2013. GHG emissions estimated by different versions of statistical data are compared and analyzed, and the effects of data adjustment on GHG emission reduction targets are discussed. The inventory covers the sources of energy activities, industrial processes, agricultural activities, waste treatments, and reports four types of GHGs: CO2, CH4, N2O, and F‐GHGs. The total GHG emissions in China increased from 3487.7 Mt CO2‐eq in 1990 to 12550.2 Mt CO2‐eq in 2013. As the largest emission source, energy activities increased its share from 77.8% to 82.1% during the period. In GHG gas type, CO2 emissions accounted for 86.2% of the total in 2013, followed by CH4 (8.1%), N2O (3.3%) and F‐GHGs (2.4%). CO2 emissions were mainly emitted from energy activities, while the total CH4 emissions were essentially determined by sources of coal mining, enteric fermentation and rice cultivation. Both direct emission from agricultural lands and adipic acid production accounted for over 50% of N2O emissions. China's F‐GHG emissions increased by 129.3 times during the period. In addition, after the energy data revision, CO2 emissions from energy activities was estimated significantly larger than most previous studies. The data revision also had a profound effect on the accomplishment of CO2 emission reduction target in relative quantity. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd.

Comparison of emissions inventories of anthropogenic air pollutants and greenhouse gases in China

Abstract. Anthropogenic air pollutant emissions have been increasing rapidly in China, leading to worsening air quality. Modelers use emissions inventories to represent the temporal and spatial distribution of these emissions needed to estimate their impacts on regional and global air quality. However, large uncertainties exist in emissions estimates. Thus, assessing differences in these inventories is essential for the better understanding of air pollution over China. We compare five different emissions inventories estimating emissions of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), and particulate matter with an aerodynamic diameter of 10 µm or less (PM10) from China. The emissions inventories analyzed in this paper include the Regional Emission inventory in ASia v2.1 (REAS), the Multi-resolution Emission Inventory for China (MEIC), the Emission Database for Global Atmospheric Research v4.2 (EDGAR), the inventory by Yu Zhao (ZHAO), and the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS). We focus on the period between 2000 and 2008, during which Chinese economic activities more than doubled. In addition to national totals, we also analyzed emissions from four source sectors (industry, transport, power, and residential) and within seven regions in China (East, North, Northeast, Central, Southwest, Northwest, and South) and found that large disagreements exist among the five inventories at disaggregated levels. These disagreements lead to differences of 67 µg m−3, 15 ppbv, and 470 ppbv for monthly mean PM10, O3, and CO, respectively, in modeled regional concentrations in China. We also find that all the inventory emissions estimates create a volatile organic compound (VOC)-limited environment and MEIC emissions lead to much lower O3 mixing ratio in East and Central China compared to the simulations using REAS and EDGAR estimates, due to their low VOC emissions. Our results illustrate that a better understanding of Chinese emissions at more disaggregated levels is essential for finding effective mitigation measures for reducing national and regional air pollution in China.

The impact of urbanization on GHG emissions in China: The role of population density

Urbanization directly drives rural to urban population migration and indirectly causes west to east migration in China, two phenomena that may significantly impact China's greenhouse gas emissions given its huge population and vast difference between the west rural and east urban areas. We analyzed these two phenomena by turning emissions into a per capita term, and extending the impact from the traditional urbanization rate effect to include population density effect. Our results show that population density has actually been the dominant demographic player in changing per capita emissions for the past two decades in China, and its elasticity changed from positive in economically less-developed provinces to negative for the developed provinces. This study therefore provides a new perspective in the study of the relationship between urbanization and greenhouse gas emissions, and our results indicate that population density change should be taken into account to accurately assess the impact of urbanization.

Apples to kangaroos: A framework for developing internationally comparable carbon emission factors for crop and livestock products

Consumption-based greenhouse gas accounting, which encompasses emissions from a nation's domestic final consumption as well as emissions embodied in imports, is gaining favor in the climate change literature for its effectiveness and consideration of equity. Unfortunately, the calculation of emissions embodied in the trade of agricultural food products is hindered by a lack of consistent and comparable emission factors.Food import quantities for every country are readily available through the United Nations Food and Agriculture Organization. Unfortunately, the carbon emission factors necessary to calculate the embodied emissions in imported foods are largely unavailable or unreliable for many countries. On top of this, different methodologies for determining carbon emission factors provide varying estimates based on different assumptions. The differences in these assumptions and methodologies can mean that attempts to compare and combine emissions based on factors from different countries become less of a comparison of apples-to-apples and more of an apples-to-oranges or even apples-to-kangaroos exercise.This study proposes a method to combine the Food and Agriculture Organization's available greenhouse gas data, production data, and agricultural yields and scaling it against benchmarks in the literature to estimate a time-series of crop and livestock carbon emission factors that are internally consistent within the Food and Agriculture Organization's data set and comparable from nation to nation. The framework provided is then used to produce a sample set of carbon emission factors for Chinese agricultural import suppliers to determine the embodied greenhouse gases in China's food imports.

Assessment of China's Greenhouse Gas Emission Reduction Target for 2030: Possibility of Earlier Peaking

Whether China's Greenhouse Gas (GHG) emission reduction target “to peak around 2030” is “fair, ambitious and adequate” or not depends on how much emphasis be placed on the historical responsibilities. However, China's peak in coal consumption may come earlier than expected, thereby advancing the peak of CO2 emission to come before 2030. In fact, the calculation based on the recent data from the National Bureau of Statistics of China released indicates that its coal consumption and CO2 emission (from fossil fuels) have almost flatted in 2014. Moreover, National Bureau of Statistics of China has upwardly adjusted the data for energy consumption and coal consumption in 2013, which led to confusion in its interpretation. Although it is difficult to say anything definite at this moment, the issue of upward adjustment of statistical data until 2013 and the recent declining trend of coal consumption and, possibly CO2 emission (from fossil fuels) can be discussed separately. All things considered, it seems more appropriate to assume that, in China, the coal consumption and CO2 emission are not likely to show significant increases in the future.

Discourse on climate change in China: A public sphere without the public

In 2007 China passed the United States to become the greatest emitter of carbon dioxide (CO2). In the same year a report was published by the United Nations Intergovernmental Panel on Climate Change. Following this report, the Chinese media began to make a link between human activity and climate change. To analyse the climate discourse that has emerged since the publication of the report, this article draws on the argument of Guobin Yang and Craig Calhoun that China has a green public sphere. In China amid the messages to consume more are messages broadcast for the masses by the Chinese state and foreign non-governmental organizations (NGOs) advocating ‘green’ and ‘low-carbon’ lifestyles with little mention of climate change or questioning of existing policies. Smaller spaces or publics exist and are primarily occupied by governmental and non-governmental elites that debate and discuss climate change in serious and playful manners. Yet it is in spaces that are not public where policies are being crafted which influence the emissions of greenhouse gases in China, while citizens focus on their economic livelihood.

Seasonal and spatial dynamics of greenhouse gas emissions under various vegetation covers in a coastal saline wetland in southeast China

Coastal saline wetlands are recognized as prominent sources of greenhouse gas emissions. However, insufficient attention has been paid to the effect of coastal wetlands in mitigating global warming caused by greenhouse gases in China. This study aims to investigate how vegetation and soil parameters affect greenhouse gas emissions in a coastal saline wetland. Fluxes of CO2, CH4, and N2O were measured simultaneously in situ using the closed static chamber technique in four different coastal tidal flats, namely, mud flat, Spartina alterniflora flat, Suaeda glauca flat, and grass flat. The measurements were obtained from September 2012 to August 2013 in the Yancheng coastal wetland, southeast China. The average fluxes across all seasons and flats varied from 10.7 to 2297.6mgCO2m−2h−1 (ecosystem respiration), from −0.368 to 4.959mgCH4m−2h−1, and from 1.5 to 65.7μgN2Om−2h−1. Higher CO2 and CH4 fluxes were observed during the summer and autumn seasons. However, the seasonal change of the N2O fluxes was complicated. For the S. alterniflora and grass flats, the highest emissions were observed during summer. For the mud and S. glauca flats, the emissions peaked during winter. The spatial variations of the three greenhouse gas fluxes in the coastal saline wetland primarily depended on vegetation type. The greenhouse gas fluxes from the three tidal flats with vegetation covers (S. alterniflora, S. glauca, and grass flats) were higher than those from the mud flat. Higher CO2 emissions were observed in the S. alterniflora flat than those in the other flats because of the higher carbon sequestration rate, together with higher net primary production and aboveground biomass. However, CH4 and N2O emissions were highest in the grass flat, followed by the S. alterniflora flat. The effects of tidal flats on the CH4 and N2O emissions differed according to the season. The S. alterniflora invasion increased the CO2 emission while slightly lowering the CH4 fluxes, compared with that of native plant communities dominated by Phragmites. Results also suggested that S. alterniflora had the highest global warming potential among the tidal flats in the coastal saline wetland.

China's 2020 clean energy target: Consistency, pathways and policy implications

China has proposed its 2020 clean energy target together with the climate change target of reducing CO2 intensity of the economy by 40–45% below the 2005 level. This article investigates the feasibility of these targets by testing their consistency under possible economic development scenarios. We analyse these targets from two perspectives: consistency with the overall economic growth and consistency with the international society's expectation on China's greenhouse gas (GHG) abatement responsibilities. The main findings are: under the recently announced 2020 target of gross domestic product (GDP) that is double the 2010 level, the adoption of a 15% clean energy target could result in excessive primary energy demand; and then with 40–45% GDP CO2 intensity reduction, CO2 emissions in 2020 could substantially exceed the International Energy Agency (IEA) 450ppm scenario for China. Thus we propose a 17% clean energy target that can reconcile the domestic plan with international expectation. Our article also outlines the pathways to realise clean energy development into 2020 and proposes policy recommendations.

Greenhouse gas emission from the total process of swine manure composting and land application of compost

Greenhouse gas (GHG) emissions from animal manure management are of great concern in China. However, there are still great uncertainties about China's GHG inventory due to the GHG emission factors partly used default values from the Intergovernmental Panel of Climate Change (IPCC) guidelines. The purpose of this study was to use a case study in Beijing to determine the regional GHG emission factors based on the combination of swine manure composting and land application of the compost with both on-site examination and a life cycle assessment (LCA). The results showed that the total GHG emission factor was 240 kgCO2eq tDS−1 (dry solids), including the direct GHG emission factor of 115 kgCO2eq tDS−1 for swine manure composting and 48 kgCO2eq tDS−1 for land application of the compost. Among the total GHG emissions of 5.06 kgCH4 tDS−1 and 0.13 kgN2O tDS−1, the swine manure composting contributed approximately 89% to CH4 emissions while land application accounted for 92% of N2O emission. Meanwhile, the GHG emission profile from the full process in Beijing in 2015 and 2020 was predicted by the scenario analysis. The composting and land application is a cost-effective way for animal manure management in China considering GHG emissions.

Study on the Cooperation Mechanism among Supply Network Enterprises in Low Carbon Economy

China's greenhouse gas emission is very critical, how to develop a low-carbon economy, build a resource-saved and environment-friendly society become the key problems. This paper study on the key issues which influence the low carbon economy, explore new cooperation mechanisms among network enterprises, and construct a green economic develop model.

Bioethanol and Biodiesel as Alternative Transportation Fuels in China: Current Status, Future Potentials, and Life Cycle Analysis

China's road transport sector is expected to be a major factor affecting national and global oil availability and prices, and is a major contributor to China's greenhouse gas emission increase and urban air pollution. Reasons for bioethanol and biodiesel to be considered as promising alternatives to conventional transportation fuels in China include energy security and environmental concerns. The present article analyzes the current status and future potential of bioethanol and biodiesel development in China, as well as the energy demand and emissions for different feedstock options from a life cycle perspective.

The Current and Future Trends in Chinese Environmental and Energy Law and Policy

In the period from 1979 to 2003, the yearly average growth rate of Gross Domestic Product (GDP) in China was 9.4 percent, and at the same time sixteen of the world's twenty most air-polluted cites were in China, according to the World Health Organization. China recently moved into second place (behind the United States) among the world's largest energy consumers. China is by far the world's largest coal consumer, devouring almost 40 percent of total global coal production annually. Oil demand is also surging within this decade. Now, China has become the third largest oil importer in the world (after the U.S. and Japan). China's current greenhouse gas emissions rank second in the world, lagging only behind the United States. The World Bank estimates that China's greenhouse gas emissions will surpass the U.S. by the year 2015, ranking China first in the world. Also, according to the U.S. Energy Information Administration (EIA), China's emission of carbon dioxide, the main by-product of fossil fuel combustion, which is regarded as the chief pollutant implicated in global warming, is likely to surpass the U.S. as the world's number one carbon dioxide emitter within two decades. As a responsible country, China is the contracting party of UN Framework of the Convention of Climate Change (UNFCCC ) and The Kyoto Protocol. The trends of China's environmental and energy law and policy have attracted and will continue to attract the attention of the countries around the world. Therefore, I would like to offer the following ideas on how to judge the current and future development trends of China's environmental and energy law and policy.

Systematical strategies for wastewater treatment and the generated wastes and greenhouse gases in China

China now faces double challenges of water resources shortage and severe water pollution. To resolve Chinese water pollution problems and reduce its impacts on human health, economic growth and social development, the situation of wastewater treatment was investigated. Excess sludge and greenhouse gases (GHGs) emitted during wastewater treatment were also surveyed. It is concluded that Chinese water pollution problems should be systematically resolved with inclusion of wastewater and the solid waste and GHGs generated during wastewater treatment. Strategies proposed for the wastewater treatment in China herein were also adequate for other countries, especially for the developing countries with similar economic conditions to China.

China's Greenhouse Gas emissions’ dynamic effects in the process of its urbanization: A perspective from shocks decomposition under long-term constraints

Abstract This paper is about to quantify the effect of China's urbanization on greenhouse gas (GHG) emissions by separating the part driven by the economic growth from the whole effect. In order to be accurate to estimate unknown parameters, this paper follows the method of Blanchard & Quah (1989), in which identifying conditions are set by assuming some shocks have no long-term effect on corresponding explained variables. We conclude that 1) Urbanization shock has an inverted hump-shaped effect on GHG emissions, in other words, nowadays the process of China's urbanization has been accompanied with saving energy and reducing emissions; 2) The growth rate of GHG emissions, owning to the GDP shock, can be raised by almost 1.53% annually and the urbanization level approximately contributes to 18% of the change of CO2 emissions based on empirical results; 3) China's emission reductions, in the short run, are actualy in expense of decreasing economic growth and delaying the p rocess of its urbanization.

Potential CO2 Emission Reduction by Development of Non-Grain-Based Bioethanol in China

Assessment of the potential CO(2) emission reduction by development of non-grain-based ethanol in China is valuable for both setting up countermeasures against climate change and formulating bioethanol policies. Based on the land occupation property, feedstock classification and selection are conducted, identifying sweet sorghum, cassava, and sweet potato as plantation feedstocks cultivated from low-quality arable marginal land resources and molasses and agricultural straws as nonplantation feedstocks derived from agricultural by-products. The feedstock utilization degree, CO(2) reduction coefficient of bioethanol, and assessment model of CO(2) emission reduction potential of bioethanol are proposed and established to assess the potential CO(2) emission reduction by development of non-grain-based bioethanol. The results show that China can obtain emission reduction potentials of 10.947 and 49.027 Mt CO(2) with non-grain-based bioethanol in 2015 and 2030, which are much higher than the present capacity, calculated as 1.95 Mt. It is found that nonplantation feedstock can produce more bioethanol so as to obtain a higher potential than plantation feedstock in both 2015 and 2030. Another finding is that developing non-grain-based bioethanol can make only a limited contribution to China's greenhouse gas emission reduction. Moreover, this study reveals that the regions with low and very low potentials for emission reduction will dominate the spatial distribution in 2015, and regions with high and very high potentials will be the majority in 2030.

China greenhouse gas emissions from agricultural activities and its mitigation strategy

China greenhouse gas emissions from agricultural activities and its mitigation strategy

Emission Inventories of Carbon-containing Greenhouse Gases in China and Technological Measures for Their Abatement

Abstract The report summarizes surveys on carbon inventories and initiatives on sustainable carbon cycling taken by the Research Center for Eco-Environmental Sciences, where the authors work/worked. The first part of the report, which appeared in the preceding issue of this journal, deals with the concept of sustainable carbon cycling, the historic evolution of carbon cycling processes in China, carbon pool enhancement, value addition, carbon sequestration and carbon balance. This very paper, as the second part of the report, covers the results of carbon dynamics modeling, emission inventories of various carbon-containing greenhouse gases and their potential abatement measures.

Climate change. Recent reductions in China's greenhouse gas emissions.

Using the most recent energy and other statistical data, we have estimated the annual trends in China9s greenhouse gas emissions for the period 1990 to 2000. The authors of this Policy Forum calculate that COemissions declined by 7.3% between 1996 and 2000, while CHemissions declined by 2.2% between 1997 and 2000. These reductions were due to a combination of energy reforms, economic restructuring, forestry policies, and economic slowdown. The effects of these emission changes on global mean temperatures are estimated and compared with the effects of concurrent changes in two aerosol species, sulfate and black carbon.