Possible Influence of the Antarctic Oscillation on Haze Pollution in North China

Abstract

In this study, the possible influence of the Antarctic oscillation (AAO) on winter haze pollution (indicated by atmospheric visibility after rain, fog, dust, snowstorms, etc. are removed) in North China (NC) was investigated. The results show that the mean winter visibility (December­January­February visibility) throughout most of eastern China is negatively correlated with the preceding AAO (August­September­ October (ASO)­AAO), especially in NC. The interannual correlation coefficient between DJF­VIS in NC and the ASO­AAO is ？0.52, which is significant at the 99% level. The negative correlation suggests that an enhancing (weakening) ASO­AAO could be conducive to increases (decreases) of haze pollution in NC in boreal winter. The responses of local and regional meteorological conditions to the ASO­AAO support the relationship between the ASO­AAO and winter air pollution in NC. A preliminary mechanism analysis shows that a positive ASO­AAO may induce a sea surface temperature warming tendency in the Northwestern Southern Indian Ocean. This warming then causes a wave train­like pattern in the upper troposphere along the jet stream and an anomalous zonal cell that weakens the regional Hadley circulation from the Maritime continents to East Asia. All of these factors are favorable to the formation of anomalous southerly and haze pollution in NC.