Simulating aerosol–radiation–cloud feedbacks on meteorology and air quality over eastern China under severe haze conditionsin winter

The aerosol-radiation-cloud feedbacks on meteorology and air quality over eastern China under severe winter haze conditions in January 2013 are simulated using the fully coupled online Weather Research and Forecasting/Chemistry (WRF-Chem) model. Three simulation scenarios including different aerosol configurations are undertaken to distinguish the aerosol's radiative (direct and semi-direct) and indirect effects. Simulated spatial and temporal variations of PM2.5 are generally consistent with surface observations, with a mean bias of −18.9 μg m−3 (−15.0%) averaged over 71 big cities in China. Comparisons between different scenarios reveal that aerosol radiative effects (direct effect and semi-direct effects) result in reductions of downward shortwave flux at the surface, 2 m temperature, 10 m wind speed and planetary boundary layer (PBL) height by up to 84.0 W m−2, 3.2°C, 0.8 m s−1, and 268 m, respectively. The simulated impact of the aerosol indirect effects is comparatively smaller. Through reducing the PBL height and stabilizing lower atmosphere, the aerosol effects lead to increases in surface concentrations of primary pollutants (CO and SO2). Surface O3 mixing ratio is reduced by up to 6.9 ppb (parts per billion) due to reduced incoming solar radiation and lower temperature, while the aerosol feedbacks on PM2.5 mass concentrations show some spatial variations. Comparisons of model results with observations show that inclusion of aerosol feedbacks in the model significantly improves model performance in simulating meteorological variables and improves simulations of PM2.5 temporal distributions over the North China Plain, the Yangtze River delta, the Pearl River delta, and central China. Although the aerosol–radiation–cloud feedbacks on aerosol mass concentrations are subject to uncertainties, this work demonstrates the significance of aerosol–radiation–cloud feedbacks for real-time air quality forecasting under haze conditions

A Modeling Study of PM2.5 Air Pollution in China: Primary and Secondary Inorganic Aerosols

Quantitative information on sources and source region contributions to particulate matter (PM) concentration in China is currently poorly understood but is urgently needed to make emission control strategies. In this study, source-oriented Community Multi-scale Air Quality (CMAQ) models are used to study the formation of and source contributions to primary and secondary PM in China. The results show that inter-regional transport of sulfate, nitrate and ammonium ion (SNA) occurs frequently, especially in the winter. The emissions from non-local regional can contribute 30-70% of the total SNA in different regions and seasons. It is also found that surface heterogeneous reactions of NO2 and SO2 and higher emissions of NH3 are needed to better reproduce the observed high concentrations of SNA in Beijing, and potentially in other areas. Residential sources account for significant fractions (19%-68% in Beijing and 6%-30% in Shanghai) of primary PM2.5, with higher contributions occur in winter. Industrial emissions are important throughout the year (15%-45% in Beijing and 39%-60% in Shanghai). Dust contributions can be as much as 20-30% in spring and fall seasons. Contributions to primary PM2.5 from other sources are relatively small. In Shanghai, local emissions account for 70-90 % of primary PM2.5. However, local emissions only contribute to 45%-55% of primary PM2.5 in Beijing. These suggest that inter-regional emission control strategies are necessary to reduce PM pollution in China. Source and source region contributions to primary PM2.5 components are determined using a novel multi-linear regression technique that combines the observation data and the source-oriented model predictions of primary PM2.5 mass concentrations

Assessment of China's virtual air pollution transport embodied in trade by using a consumption-based emission inventory

Substantial anthropogenic emissions from China have resulted in serious air pollution, and this has generated considerable academic and public concern. The physical transport of air pollutants in the atmosphere has been extensively investigated; however, understanding the mechanisms how the pollutant was transferred through economic and trade activities remains a challenge. For the first time, we quantified and tracked China's air pollutant emission flows embodied in interprovincial trade, using a multiregional input - output model framework. Trade relative emissions for four key air pollutants (primary fine particle matter, sulfur dioxide, nitrogen oxides and non-methane volatile organic compounds) were assessed for 2007 in each Chinese province. We found that emissions were significantly redistributed among provinces owing to interprovincial trade. Large amounts of emissions were embodied in the imports of eastern regions from northern and central regions, and these were determined by differences in regional economic status and environmental policy. It is suggested that measures should be introduced to reduce air pollution by integrating cross-regional consumers and producers within national agreements to encourage efficiency improvement in the supply chain and optimize consumption structure internationally. The consumption-based air pollutant emission inventory developed in this work can be further used to attribute pollution to various economic activities and final demand types with the aid of air quality models

A county-level estimate of PM2.5 related chronic mortality risk in China based on multi-model exposure data

BACKGROUND: Ambient fine particulate matter (PM2.5) pollution is currently a serious environmental problem in China, but evidence of health effects with higher resolution and spatial coverage is insufficient. OBJECTIVE: This study aims to provide a better overall understanding of long-term mortality effects of PM2.5 pollution in China and a county-level spatial map for estimating PM2.5 related premature deaths of the entire country. METHOD: Using four sets of satellite-derived PM2.5 concentration data and the integrated exposure-response model which has been employed by the Global Burden of Disease (GBD) to estimate global mortality of ambient and household air pollution in 2010, we estimated PM2.5 related premature mortality for five endpoints across China in 2010. RESULT: Premature deaths attributed to PM2.5 nationwide amounted to 1.27million in total, and 119,167, 83,976, 390,266, 670,906 for adult chronic obstructive pulmonary disease, lung cancer, ischemic heart disease, and stroke, respectively; 3995 deaths for acute lower respiratory infections were estimated in children under the age of 5. About half of the premature deaths were from counties with annual average PM2.5 concentrations above 63.61μg/m3, which cover 16.97% of the Chinese territory. These counties were largely located in the Beijing-Tianjin-Hebei region and the North China Plain. High population density and high pollution areas exhibited the highest health risks attributed to air pollution. On a per capita basis, the highest values were mostly located in heavily polluted industrial regions. CONCLUSION: PM2.5-attributable health risk is closely associated with high population density and high levels of pollution in China. Further estimates using long-term historical exposure data and concentration-response (C-R) relationships should be completed in the future to investigate longer-term trends in the effects of PM2.5

Concentration, source, and health risk assessment of polycyclic aromatic hydrocarbons: a pilot study in the Xuanwei lung cancer epidemic area, Yunnan Province, China

Polycyclic aromatic hydrocarbons (PAHs) are toxic and hazardous volatile environmental pollutants that have been studied as possible major causative agents of lung cancer in Xuanwei. In this paper, indoor and outdoor PM2.5 samples were collected from two homes at different time periods in Hutou, the lung cancer epidemic area in Xuanwei. The results showed that PAH pollution levels from coal combustion in Xuanwei lung cancer epidemic area were significant. The mass concentrations of total PAHs, major carcinogenic compounds, and benzo[a]pyrene-based equivalent concentration (BaPeq) were significantly higher in the coal-using home than in the electricity-using home. For the coal-using home, the PAHs were mainly derived from coal combustion. For the electricity-using home, the PAHs might have been a combination of traffic and coal combustion sources. The human health risk due to inhalation exposure to the PAHs was represented by the incremental lifetime cancer risk (ILCR) of the inhalation exposure. The results showed that the indoor cancer risk for the coal-using home in Xuanwei is higher than that of the electricity-using home and much higher than that of Chinese megacities such as Beijing and Tianjin. Long-term exposure to indoor coal-burning environments containing high levels of PAHs may be one of the main reasons for the high incidence of lung cancer in Xuanwei

Electric Vehicles in China: Emissions, Health Impacts, and Equity

E-bikes in China are the single largest adoption of alternative fuel vehicles in history, with more than 100 million e-bikes purchased in the past decade and vehicle ownership about 2× [time] larger for e-bikes as for conventional cars; e-cars sales, too, are rapidly growing. Electric vehicles (EVs) in China are being considered as a strategy to improve air quality, energy efficiency, and reduce health impacts due to transport emissions. Because EVs have different pollution sources, namely electric generating units (EGUs), quantitative analysis for health impacts requires understanding the exposure efficiency of related pollution sources. In this dissertation, EVs will be analyzed in the context of the impacts on the environment, the differences in exposure efficiency of pollutants, the impacts on health, and the distribution of those impacts among different sectors of the population. This study compares emissions (CO2 [Carbon Dioxide], PM2.5 [Particulate Matter], NOX [Nitrogen Oxide], HC [Hydrocarbon]) and environmental health impacts (primary PM2.5) from the use of conventional vehicles (CVs) and EVs in 34 major cities in China. CO2 emissions (g km-1) vary and are an order of magnitude greater for e-cars (135–274) and CVs (150-180) than for e-bikes (14–27). PM2.5 emission factors generally are lower for CVs (gasoline or diesel) than comparable EVs. However, intake fraction is often greater for CVs than for EVs because combustion emissions are generally closer to population centers for CVs (tailpipe emissions) than for EVs (EGU emissions). For most cities, the net result is that primary PM2.5 environmental health impacts per passenger-km are greater for e-cars than for gasoline cars (3.6× on average), lower for e-cars than for diesel cars (2.5× on average) and equal between e-cars and diesel buses. In contrast, e-bikes yield lower environmental health impacts per passenger-km than the three CVs investigated: gasoline cars (2×), diesel cars (10×), and diesel buses (5×). In addition, adoption of EVs could cause environmental equity problems in China at this time, since a vast majority (\u3e83%) of pollutant emissions inhaled and subsequent health effects due to urban EV use could be distributed to communities whose incomes are lower than the cities where EVs are promoted. The findings highlight the importance of considering exposures, and especially the proximity of emissions to people, when evaluating environmental health impacts and equity concerns for EVs

Air Quality Research Using Remote Sensing

Air pollution is a worldwide environmental hazard that poses serious consequences not only for human health and the climate but also for agriculture, ecosystems, and cultural heritage, among other factors. According to the WHO, there are 8 million premature deaths every year as a result of exposure to ambient air pollution. In addition, more than 90% of the world’s population live in areas where the air quality is poor, exceeding the recommended limits. On the other hand, air pollution and the climate co-influence one another through complex physicochemical interactions in the atmosphere that alter the Earth’s energy balance and have implications for climate change and the air quality. It is important to measure specific atmospheric parameters and pollutant compound concentrations, monitor their variations, and analyze different scenarios with the aim of assessing the air pollution levels and developing early warning and forecast systems as a means of improving the air quality and safeguarding public health. Such measures can also form part of efforts to achieve a reduction in the number of air pollution casualties and mitigate climate change phenomena. This book contains contributions focusing on remote sensing techniques for evaluating air quality, including the use of in situ data, modeling approaches, and the synthesis of different instrumentations and techniques. The papers published in this book highlight the importance and relevance of air quality studies and the potential of remote sensing, particularly that conducted from Earth observation platforms, to shed light on this topic

Simulating aerosol–radiation–cloud feedbacks on meteorology and air quality over eastern China under severe haze conditionsin winter

The aerosol-radiation-cloud feedbacks on meteorology and air quality over eastern China under severe winter haze conditions in January 2013 are simulated using the fully coupled online Weather Research and Forecasting/Chemistry (WRF-Chem) model. Three simulation scenarios including different aerosol configurations are undertaken to distinguish the aerosol's radiative (direct and semi-direct) and indirect effects. Simulated spatial and temporal variations of PM_2.5 are generally consistent with surface observations, with a mean bias of −18.9 μg m⁻³ (−15.0%) averaged over 71 big cities in China. Comparisons between different scenarios reveal that aerosol radiative effects (direct effect and semi-direct effects) result in reductions of downward shortwave flux at the surface, 2 m temperature, 10 m wind speed and planetary boundary layer (PBL) height by up to 84.0 W m⁻², 3.2°C, 0.8 m s⁻¹, and 268 m, respectively. The simulated impact of the aerosol indirect effects is comparatively smaller. Through reducing the PBL height and stabilizing lower atmosphere, the aerosol effects lead to increases in surface concentrations of primary pollutants (CO and SO₂). Surface O₃ mixing ratio is reduced by up to 6.9 ppb (parts per billion) due to reduced incoming solar radiation and lower temperature, while the aerosol feedbacks on PM_2.5 mass concentrations show some spatial variations. Comparisons of model results with observations show that inclusion of aerosol feedbacks in the model significantly improves model performance in simulating meteorological variables and improves simulations of PM_2.5 temporal distributions over the North China Plain, the Yangtze River delta, the Pearl River delta, and central China. Although the aerosol–radiation–cloud feedbacks on aerosol mass concentrations are subject to uncertainties, this work demonstrates the significance of aerosol–radiation–cloud feedbacks for real-time air quality forecasting under haze conditions

Size Specific Distribution Analysis of Perfluoroalkyl Substances In Atmosphere -Development and Verification

13301甲第4481号博士（学術）金沢大学博士論文本文Full 以下に掲載予定：Aerosol and Air Quality Research Taiwan Association for Aerosol Research. 共著者：Ge H, Yamazaki E, Yamashita N, Taniyasu S, Zhang T, Hata M, Furuuchi M

Air Pollution Control and Sustainable Development

This book brings together the latest research findings on the state of air pollution control and its impact on economic growth in different countries. The book has substantial content and rich discussion. It is suitable for students and researchers at different levels to learn the status of air pollution, governance policies and their effects, and the relationship between pollution control and economic growth in countries around the world