On the relationship between the Hadley circulation and the tropospheric ozone Change in East asian and West Pacific region

Based on analyzing the ozone mixing ratio (ρ3) and wind field data,and by applying the backward trajectory method,the effect of Hadley circulation on the distribution of tropospheric ozone over the East Asia and West Pacific region has been explored in this paper.The probability on each direction of the four key-points'backward trajectories has been calculated.Meanwhile,the correlation coefficient between the probability and ρ3 has been computed.As a result the influence of Hadley circulation's horizontal advection on the tropospheric ozone distribution has been found out.The results show that:firstly,at the low-level troposphere over Qinghai-Tibet Plateau region,Hadley circulation's horizontal advection leads to the reducing of the mixing ratio of ozone,while at the high-level of the corresponding southern hemisphere,its overall effect is to increase the ozone. Secondly,at the low-level troposphere over West Pacific region,its role is to reduce the mixing ratio of ozone and corresponding to the high-level troposphere of southern hemisphere,and its impact is weaker. What's more,the horizontal advection of the East Asian monsoon may have an effect on the ozone distribution which is worth further studying.