基于VAR模型对武汉PM_(2.5)及其影响因素的研究

Study on the Relationship Between PM_(2.5) and Its Influencing Factors in Wuhan Based on VAR

基于武汉市城区2017年1月1日～2017年12月31日空气质量指标和气象指标的观测数据,建立了一个自回归模型(VAR)模型,用以分析相关指标对PM_(2.5)的影响作用,并运用广义脉冲函数和方差分解方法对建立的VAR模型进行了分析。实证表明:武汉市PM_(2.5)与其影响因素所构成的系统是稳定的,当二氧化硫(SO2)、一氧化碳(CO)、臭氧(O3)、气温、风速受到一个正向变化冲击时,则PM_(2.5)浓度会增加,降水量的正向变化会引起PM_(2.5)浓度的降低,其中降水量、温度和SO2是影响PM_(2.5)浓度的主要因素。

A VAR model was created based on the observational data of air quality and meteorological conditions in the urban areas in Wuhan from January 1,2017 to December 31,2017 and used to make an analysis of the effect of the related indexes on the local PM2.5.In addition,this paper also analyzed the VAR model by means of variance decomposition and generalized impulse response function.The empirical results showed that the system composed of PM2.5 and its influencing factors was stable.The concentration of PM2.5 would increase when SO2,CO,O3,temperature and wind were affected by apositive change.A positive change in the rainfall might lead to a decrease in PM2.5 concentration.Rainfall,temperature and SO2 were the main factors that affected the concentration of PM2.5 in the urban areas of Wuhan.