Impact of residual layer transport on air pollution in Beijing, China

A brown air pollution haze that forms over some international cities during the winter has been found to be associated with negative health outcomes and high surface air pollution levels. Previous research has demonstrated a well-established link between the structure of the atmospheric boundary layer (ABL) and surface air quality; however, the degree to which the structure of the ABL influences for formation of local-scale brown haze is unknown. Using continuous ceilometer data covering seven consecutive winters, we investigate the influence of the structure of the ABL in relation to surface air pollution and brown haze formation over an urban area of complex coastal terrain in the Southern Hemisphere city of Auckland, New Zealand. Our results suggest the depth and evolution of the ABL has a strong influence on severe brown haze formation. When days with severe brown haze are compared with those when brown haze is expected but not observed (based on favorable meteorology and high surface air pollution levels), days with severe brown haze are found to coincide with significantly shallower daytime convective boundary layers (~ 48% lower), and the nights preceding brown haze formation are found to have significantly shallower nocturnal boundary layers (~ 28% lower). On severe brown haze days the growth rate during the morning transition phase from a nocturnal boundary layer to a convective daytime boundary layer is found to be significantly reduced (70 m h-1) compared to days on which brown haze is expected but not observed (170 m h-1). Compared with moderate brown haze, severe brown haze conditions are found to be associated with a significantly higher proportion of days with a distinct residual layer present in the ceilometer profiles, suggesting the entrainment of residual layer pollutants may contribute to the severity of the haze. This study illustrates the complex interaction between the ABL structure, air pollution, and the presence of brown haze, and demonstrates the utility of a ceilometer instrument in understanding and predicting the occurrence of brown haze events.

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A dragon eating its own tail: public control of air pollution information in China

Environment and Development Economics ◽

10.1017/s1355770x18000414 ◽

2018 ◽

Vol 24 (1) ◽

pp. 1-22 ◽

Cited By ~ 1

Author(s):

Chiara Ravetti ◽

Tim Swanson ◽

Yana Jin ◽

Quan Mu ◽

Shiqiu Zhang

Keyword(s):

Air Pollution ◽

Labour Force ◽

Public Information ◽

Household Survey ◽

Government Control ◽

Alternative Source ◽

The Us ◽

The Media ◽

Public Signal ◽

Beijing China

AbstractThis paper analyses the implications of government control over public information about air pollution. First, we model the incentives for a local government with control over the media to affect popular perception concerning pollution. We argue that biased announcements can influence the inflows of labour force in a municipality beyond economic factors. Then, we examine some evidence on information misreporting in the context of Beijing, China. We show that official air pollution announcements diverge systematically from an alternative source of information, provided by the US Embassy. The results point at a manipulation of popular perception consistent with the motives indicated in our model. Furthermore, using an original household survey, we examine whether the distorted public signal affects agents' behaviour. We find that households that depend upon government-controlled media are significantly less responsive to pollution peaks.

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The Impact of “Coal to Gas” Policy on Air Quality: Evidence from Beijing, China

Energies ◽

10.3390/en13153876 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3876 ◽

Cited By ~ 2

Author(s):

Zhe Liu ◽

Xueli Chen ◽

Jinyang Cai ◽

Tomas Baležentis ◽

Yue Li

Keyword(s):

Air Pollution ◽

Particulate Matter ◽

Air Quality ◽

Energy Use ◽

Northern China ◽

Heating System ◽

Use Efficiency ◽

The Government ◽

The Impact ◽

Beijing China

Air pollution has become an increasingly serious environmental problem in China. Especially in winter, the air pollution in northern China becomes even worse due to winter heating. The “coal to gas” policy, which uses natural gas to replace coal in the heating system in winter, was implemented in Beijing in the year 2013. However, the effects of this policy reform have not been examined. Using a panel dataset of 16 districts in Beijing, this paper employs a first difference model to examine the impact of the “coal to gas” policy on air quality. Strong evidence shows that the “coal to gas” policy has significantly improved the air quality in Beijing. On average, the “coal to gas” policy reduced sulfur dioxide (SO2), nitrogen dioxide (NO2), particulate matter smaller than 10 µm (PM10), particulate matter smaller than 2.5 µm (PM2.5) and carbon monoxide (CO) by 12.08%, 4.89%, 13.07%, 11.94% and 11.10% per year, respectively. We find that the “coal to gas” policy is more effective in areas with less energy use efficiency. The finding of this paper suggests that the government should continue to implement the “coal to gas” policy, so as to alleviate the air pollution in Beijing, China.

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