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Climatic Factors and Their Availability in Estimating Long‐Term Variations of Fine Particle Distributions Over East China

Concerns about air pollutions in China have made fine particulate matter (PM2.5) estimation a hot research topic in recent years. Using satellite‐based PM2.5 data obtained over East China in 2000–2015, climatic factors affecting the PM2.5 variability were revealed in different seasons. Relevant climatic factors were used to estimate seasonal PM2.5 distributions by combining empirical orthogonal function with stepwise regression. The assessment results indicate a greater impact by climatic factors on PM2.5 variability in western East China than over coastal areas, and more significant influence by climatic factors on PM2.5 variability also occurs in summer and autumn than spring and winter. Our favorable results for PM2.5 estimation in 2016 further validate the capability of the estimation method for PM2.5 distributions based on climatic factors. Individual contributions of dominant climatic factors to PM2.5 variability over East China during the past 16 years range from 5% to 30%. In conclusion, climatic factors play nonnegligible roles in modulating PM2.5 concentrations, and they can feasibly be considered as predictors in the estimation of PM2.5 concentrations in East China. Our work underscores the importance of climate change impacts on air pollutions and improves air quality forecasts over East China.