[Characteristics of Aerosol Particulate Concentrations and Their Climate Background in Shanghai During 2007-2016]

We use daily aerosol particulate matter<10 μm (PM₁₀) 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 PM₁₀ 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 PM₁₀ concentrations. The results showed an oscillating downward trend in the annual average concentrations of PM₁₀ in Shanghai, whereas seasonally, PM₁₀ concentrations were relatively high in winter and showed two peaks with a low in between. PM₁₀ 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 PM₁₀ 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 PM₁₀ concentrations. When the wind field at 850 hPa was easterly, the wind speed was relatively large and resulted in relatively low PM₁₀ concentrations.