Relationships of wind speed and precipitable water vapor with regional PM2.5 based on WRF-Chem model

Abstract

Air pollution, especially the particulate matter (PM2.5) remains to be a severe problem for the environmental managers and researchers because it causes many respiratory diseases even casualties and huge economic losses. Therefore, it is significant to study the distribution characteristics of regional PM2.5 and analyze the mutual influence relationship between it and some influencing factors including air humidity, wind speed, and atmospheric boundary conditions. Some scholars have studied the relationship between PM2.5 and the atmospheric planetary boundary layer or relative humidity. However, the relationships between air pollution and meteorological conditions in China has been extensively studied in recent years. Therefore, the association between the pollution and precipitation water vapor and wind speed in the northeast of China (e.g., Jilin and Heilongjiang province) could be strengthened. Considering all components in the atmosphere affecting each other and the ability of Weather Research and Forecast (WRF) and WRF-Chemistry (WRF-Chem) simulating all of the atmospheric parameters, we utilized the WRF and WRF-Chem to simulate the precipitable water vapor, wind speed, and PM2.5. Then first, the PM2.5 concentration values predicted from WRF-Chem are validated with those at the ground stations to evaluate the accuracy of WRF-Chem model. Second, the relationship analysis between the PM2.5 and wind speed or PWV was done. And the results demonstrate that the wind is helpful to decrease the severe air pollution in winter while the precipitable water vapor plays a small effect on the elimination of the particulate matter. WRF-Chem is a potential and effective tool for the study of air pollution.