Analysis of the Variation of Atmospheric Composition in the Upper Troposphere during a Strong Convection in Eastern China in Summer
我国东部夏季一次强对流活动过程中对流层上部大气成分变化的分析

The distribution of atmospheric composition, including carbon monoxide (CO), ozone (O3), water vapor (H2O), and ice water content (IWC), during a strong convective weather occurring in the Jianghuai areas is investigated based on measurements by the MLS (Microwave Limb Sounder) on the Aura satellite. Results show that the increase of CO mixing ratio at 200 hPa is 0.12 ppm, the decrease of O3 mixing ratio at 70 hPa is about 0.30 ppm, and the increase of H2O mixing ratio at 250 hPa is 400 ppm. The value of IWC has a sharp growth before the surface heavy rain occurs, and its maximum at 200 hPa is about 0.03 g/m3. The consistency variation between vertical velocity and mixing ratio of CO and O3 indicates that the vertical transport is a conceivable mechanism changing the distribution of atmospheric composition in the upper troposphere and the lower stratosphere. Besides, H2O mixing ratio and IWC also increase obviously when the convection is triggered, but the growth is limited below the tropopause. This suggests that not only the vertical transport but also the microphysical processes in the convection system decide the quality and phase of water in the upper troposphere.