Abstract: To explore the characteristics of PM2.5 and PM10 in Chengdu, China, and their relationship with meteorological factors, monthly average concentrations of PM2.5 and PM10 in Chengdu from 2015 to 2018 were collected, and their relationships with meteorological factors were analyzed by using Pearson correlation analysis method. The results show that: (1) Pue to the implementation of a series of air pollution control measures since 2015, the average annual concentration of PM2.5, PM10 in Chengdu shows a slowly decreasing trend year by year. And the seasonal PM2.5, PM10 concentration in Chengdu from 2015 to 2018 decreased in the order of winter, spring, autumn and summer. (2) Different meteorological factors have different effects on the monthly average concentration of PM2.5 and PM10 in Chengdu. The concentrations of PM2.5 and PM10 show a high negative linear correlation with temperature and precipitation, which indicates that temperature and precipitation are two key factors affecting the monthly average concentrations of PM2.5 and PM10 in Chengdu. Sunshine duration, monthly average wind speed and relative humidity are also negatively correlated with PM2.5 and PM10 monthly average concentrations. However, compared with precipitation and temperature, the linear correlation between sunshine duration, monthly average wind speed and PM2.5, PM10 is lower, while the linear correlation between relative humidity and PM2.5, PM10 is even weaker, and less significant, indicating that the change of relative humidity has little effect on the accumulation and diffusion of PM2.5 and PM10 in Chengdu.

Key words: fine particulate matter, inhalable particles, temperature, precipitation, wind speed