On-road mobile mapping of spatial variations and source contributions of ammonia in Beijing, China.

Ammonia (NH) measurements were performed with a mobile platform deploying a cavity ring-down spectroscopy NH analyzer in Beijing. The transect and loop sampling strategy revealed that the Beijing urban area is more strongly affected by NH emissions than surrounding areas. Although average enhancements of on-road NH were small compared to background levels, traffic emissions clearly dominated city enhancements of NH, carbon dioxide (CO), acetaldehyde and acetone.

Long-term declining in carbon monoxide (CO) at a rural site of Beijing during 2006-2018 implies the improved combustion efficiency and effective emission control.

Carbon monoxide (CO) is primarily the result of incomplete combustion, which has important impacts on the atmospheric chemical cycle and climate. Improved quantitative characterization of long-term CO trends is important for both atmospheric modeling and the design and implementation of policies to efficiently control multiple pollutants. Due to the limitations of high time-resolution and high-quality long-term observational data, studies on long-term trends in the CO concentration in China are quite limited.

Multilevel air quality evolution in Shenyang: Impact of elevated point emission reduction.

Visibility observed at different altitudes is favorable to understand the causes of air pollution. We conducted 4-years of observations of visibility at 2.8 and 60 m and particulate matter (PM) concentrations from 2015 to 2018 in Shenyang, a provincial city in Northeast China.

[Application of ARIMA Model for Mid- and Long-term Forecasting of Ozone Concentration].

Ozone pollution has recently become a severe air quality issue in the Beijing-Tianjin-Hebei region. Due to the lack of a precursor emission inventory and complexity of physical and chemical mechanism of ozone generation, numerical modeling still exhibits significant deviations in ozone forecasting. Owing to its simplicity and low calculation costs, the time series analysis model can be effectively applied for ozone pollution forecasting.

Regional transport and urban emissions are important ammonia contributors in Beijing, China.

Measuring ammonia (NH) is important for understanding the role of NH in secondary aerosol formation and the atmospheric deposition of reactive N. In this study, NH was measured in an urban area, a background region, and a tunnel in Beijing. The average NH concentrations between September 2017 and August 2018 were 24.

Acute and Cumulative Effects of Haze Fine Particles on Mortality and the Seasonal Characteristics in Beijing, China, 2005-2013: A Time-Stratified Case-Crossover Study.

We observed significant effects of particulate matter (PM) on cause-specific mortality by applying a time-stratified case-crossover and lag-structure designs in Beijing over a nine-year study period (2005-2013). The year-round odds ratio (OR) was 1.005 on the current day with a 10 μg/m increase in PM for all-cause mortality.

[Using Multiple Linear Regression Method to Evaluate the Impact of Meteorological Conditions and Control Measures on Air Quality in Beijing During APEC 2014].

Meteorological conditions have important impact on the diffusion and transport of air pollutants, thus separating and quantifying the impact of meteorological factors is a prerequisite for evaluation of air pollution control measures. Using observation data on SO, NO, NO, NO, CO, PM, PM, and PM as well as meteorological factors at the Chaoyang site, an urban site in Beijing, we evaluated the impact of meteorological conditions and control measures on air quality in Beijing during APEC 2014 (from 15 October to 30 November, 2014) by the multiple linear regression method. The simulation performance of a multivariate linear regression model based on the parameters of meteorological factors for predicting pollutant concentration assuming constant emission conditions were ideal, produced a range of determination coefficient () of 0.

Long-term trend of chemical composition of atmospheric precipitation at a regional background station in Northern China.

Understanding the trend of chemical composition of precipitation is of great importance for air pollution control strategies in Northern China. A comprehensive study on the long-term chemical compositions of precipitation was carried out from 2003 to 2014 at the Shangdianzi (SDZ) regional background station in northern China. All samples were analyzed for pH, electrical conductivity and major ions (F, Cl, NO, SO, NH, Mg, Ca, K and Na).