华北冬季地面环流型对不同城市大气能见度的影响研究

Influence of Surface Circulation Types on Visibility of Different Cities in North China in Winter

采用Lamb-Jenkinson客观环流分型方法,对华北地区2014年-2018年冬季日均海平面气压场进行分型,并分析了不同环流型下不同城市冬季能见度的分布特征。结果表明A型、N型、NE型、AN型、E型、ANE型、C型、AE型和SE型等9种环流出现频率超过3%,为主要环流型;其中C、E、SE型为全区性低能见度环流型,A、N、AN型为全区性高能见度环流型,NE、AE、ANE型对不同城市能见度的影响存在局地差异;低能见度环流型对应高相对湿度、高PM2.5浓度,而高能见度环流型对应低相对湿度、低PM2.5浓度。

By using Lamb-Jenkinson objective circulation classification method,the daily average sea level pressure fields in North China during the winter of 2014-2018 are classified,and the distribution characteristics of visibility in different cities under different circulation types are analyzed.The results show that the main circulation types are A,N,NE,AN,E,ANE,C,AE and SE.The frequencies of these circulation types are more than 3%.Among them,C,E and SE are the low visibility circulation types in the whole region.A,N and AN are the high visibility circulation types in the whole region.Type NE,AE and ANE have local differences in their effects on visibility of different cities.The low visibility circulation types correspond to high relative humidity and high PM2.5,while the high visibility circulation types correspond to low relative humidity and low PM2.5.