Based on the meteorological data and the mass concentration monitoring data of major atmospheric pollutants of Xi'an in 2017, the climate change, air pollution status and temporal and spatial evolution characteristics of pollutant mass concentration in Xi'an City were comprehensively analyzed in this study. The results show that the annual average wind speed in Xi'an is 2.43 m/s, the average temperature is 19.00 °C, and the total precipitation is 649 mm. The mass concentration of PM2.5
in winter and spring is generally higher than that in summer and autumn. Using SPSS to analyze the correlation between pollutants and meteorological factors, it is suggested that the changes of concentration of particulate matter and of such gaseous pollutants as CO and SO2
are negatively correlated with average temperature, precipitation and wind speed, while O3
is positively correlated with average temperature, precipitation, and wind speed. In addition, the Lagrange hybrid particle trajectory model is used to simulate the backward trajectory of the airflow in Xi'an for 48 hours. Combining the concentration data of PM2.5
with air mass backward trajectories, a potential source contribution function model (PSCF) and a concentration-weighted trajectory method (CWT) are used to analyze the influence of PM2.5
concentration and potential source area distribution characteristics in Xi'an. The results show that more than 50% of the airflow backward trajectory comes from the Northwest direction, and the main potential sources of PM2.5
of Xi'an are the cities of southern Shaanxi and the border regions of neighboring provinces to southern Shannxi.