A numerical study of contributions to air pollution in Beijing during CAREBeijing-2006

Abstract

Abstract. An online air pollutant tagged module has been developed in the Nested Air Quality Prediction Model System (NAQPMS) to investigate the impact of local and regional sources on the air pollutants in Beijing during the Campaign of Air Quality Research in Beijing 2006(CAREBeijing-2006). The NAQPMS model shows high performance in simulating sulfur dioxide (SO 2 ), particulate matter (PM 10 ), nitrogen dioxide (NO 2 ), and ozone (O 3 ) with overall better agreements with the observations at urban sites than rural areas. With the tagged module, the air pollutant contributions from local and regional sources to the surface layer (about 30 m) and the upper layer (about 1.1 km) in Beijing are differentiated and estimated. The air pollutants at the surface layer in Beijing are dominated by the contributions from local sources, accounting for 65 % of SO 2 , 75 % of PM 10 and nearly 90 % of NO 2 , respectively, comparatively, the 1.1 km layer has large source contributions from the surrounding regions (e.g., southern Beijing), accounting for more than 50 % of the SO 2 and PM 10 concentrations. County scale analysis is also performed and the results suggest that Tianjin is the dominant source of SO 2 in Pinggu County, and Langfang, Hebei is the most important regional contributor to PM 10 in Beijing. Moreover, the surrounding regions show larger impact on SO 2 , PM 10 and NO 2 in the eastern counties of Beijing (e.g., Pinggu, Tongzhou and Daxing) than those in western Beijing, which is likely due to the Beijing's semi-basin topography and the summer monsoon. Our results indicate that the efforts to control the air pollutants in Beijing should focus on controlling both local and regional emissions.

Gravity-Current-Driven Transport of Haze from the North China Plain to Northeast China in Winter 2010-Part 2: Model Simulation with Tagged Tracers

“…Similar analyses have been employed in previous studies (Davis et al 2003;Kondo et al 2004;Sudo and Akimoto 2007;Li et al 2008). The study by Wu et al (2011) provides more details on the tagged method. This study tagged 23 emissions regions in the model domain on the basis of data from the regional administrative system and the position relative to four representative sites in NE China (Fig.…”

“…Most air pollution studies to date have focused on more developed mega cities such as Beijing, Shanghai, and Pearl River Delta (PRD), whose population constitutes solely 10% of the total population (Gao et al 2011). Several review papers have discussed the challenges encountered in mitigating the deterioration of urban air quality (He et al 2001;Shao et al 2006;Chan and Yao 2008).…”

“…It adversely affects not only human health and the environment (Salma et al 2002;Tie and Cao 2009) but also the regional-or global-scale climate by altering solar and infrared radiation in the atmosphere (Chen and Wu 2011;Han et al 2012). Recently, satellite observations have suggested that haze, which is one of the most disastrous weather events in Chinese cities, has been found to more frequently occur on a large scale, covering areas up to several thousand square kilometers, suggesting that air pollution is no longer limited to mega cities (Gao et al 2011).…”

Investigation of Particulate Matter Regional Transport in Beijing Based on Numerical Simulation

“…Strong turbulence enhances the local contribution in the upper atmosphere and results in a large near-surface TBCR. The TBCR exhibits significant change in vertical direction (Wu et al, 2011). With increasing altitude, the TBCR increases rapidly from 10% to 90% below 3 km, implying that local contributions and regional transport are more significant at the near-surface and upper atmosphere, respectively.…”

A Quantitatively Operational Judging Method for the Process of Large Regional Heavy Haze Event Based on Satellite Remote Sensing and Numerical Simulations

“…Numerical simulation technology has been widely used to predict the pollutant PM 2.5 concentration and also to analyze the process of haze in recent years [24,25] since it is characteristic of high time frequency and good regional coverage, but regarding the accuracy of the pollution source list, the atmospheric field results and its inter physical and chemical mechanism, it has relatively low accuracy. Under normal conditions, its accuracy is 40%, when in heavy pollution days, low estimations often occur.…”