We use daily aerosol particulate matter<10 μm (PM) concentration data from 2006 to 2016 in Shanghai along with meteorological elements (wind and temperature), atmospheric stability, temperature inversion, and upper atmosphere circulation data, to analyze the variation characteristics of the PM concentrations and differences of the winter climate background. We establish a multivariate linear stepwise regression equation, and also compare and analyze differences in the upper atmospheric circulation by selecting the years with the highest and lowest PM concentrations. The results showed an oscillating downward trend in the annual average concentrations of PM in Shanghai, whereas seasonally, PM concentrations were relatively high in winter and showed two peaks with a low in between. PM concentrations were negatively correlated with the daily average wind speed and the daily mixing layer height at 20:00, and positively correlated with the frequency of northwest wind, the mean daily temperature, and the frequency of stable weathers and thermal inversion at 20:00. When the 500 hPa height field in the northern part of China was a positive anomaly in winter, a warm winter prevailed and led to high PM concentrations. When the 500 hPa height field was a negative anomaly, cold air frequently moved southward to result in relatively low temperatures, which caused relatively low PM concentrations. When the wind field at 850 hPa was easterly, the wind speed was relatively large and resulted in relatively low PM concentrations.
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http://dx.doi.org/10.13227/j.hjkx.201904219 | DOI Listing |
Environ Res
January 2025
Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA; The Department of Geography and Environmental Development, Ben-Gurion University of the Negev, Beer Sheva, Israel.
Air-pollution monitoring is sparse across most of the United States, so geostatistical models are important for reconstructing concentrations of fine particulate air pollution (PM) for use in health studies. We present XGBoost-IDW Synthesis (XIS), a daily high-resolution PM machine-learning model covering the contiguous US from 2003 through 2023. XIS uses aerosol optical depth from satellites and a parsimonious set of additional predictors to make predictions at arbitrary points, capturing near-roadway gradients and allowing the estimation of address-level exposures.
View Article and Find Full Text PDFEnviron Pollut
January 2025
State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address:
Ammonia (NH) is crucial in fine particulate matter (PM) formation, but past estimations on industrial NH emissions remain highly uncertain. In this study, the flow of NH within air pollution control devices (APCDs) were investigated basing on material flow analysis with in-situ measurements of NH concentrations at the inlets and outlets of each APCD. Then, by combing emission factors updated with recent in-situ measurements and provincial-level activity data from statistical yearbooks and associated reports, NH emissions from various industrial sources, as well as their spatial distribution across China in 2020, were evaluated.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Lung Biology, Department of Experimental Medical Sciences, Lund University, 221 84 Lund, Sweden.
Particulate matter (PM) is a major component of ambient air pollution. PM exposure is linked to numerous adverse health effects, including chronic lung diseases. Air quality guidelines designed to regulate levels of ambient PM are currently based on the mass concentration of different particle sizes, independent of their origin and chemical composition.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong SAR 999077, China.
Chlorine radicals (Cl) are highly reactive and affect the fate of air pollutants. Several field studies in China have revealed elevated levels of daytime molecular chlorine (Cl), which, upon photolysis, release substantial amounts of Cl but are poorly represented in current chemical transport models. Here, we implemented a parametrization for the formation of daytime Cl through the photodissociation of particulate nitrate in acidic environments into a regional model and assessed its impact on coastal air quality during autumn in South China.
View Article and Find Full Text PDFSci Total Environ
January 2025
School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Rd., Shanghai 200240, China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, 800 Dongchuan Rd., Shanghai 200240, China; Shanghai Urban Forest Ecosystem Research Station, National Forestry and Grassland Administration, 800 Dongchuan Rd., Shanghai 200240, China; Key Laboratory for Urban Agriculture, Ministry of Agriculture and Rural Affairs, 800 Dongchuan Rd., Shanghai 200240, China. Electronic address:
Biogenic volatile organic compounds (BVOCs) are emitted by urban vegetation and can interact with anthropogenic pollutants to generate secondary organic aerosols (SOA) that are atmospheric pollutants in urban environments. In urban forests, SOA comprise up to 90 % of all fine aerosols (particulate matter smaller than 1 μm [PM]) in the summer. PM can greatly affect urban air quality and public health.
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