The origin and seasonal characteristics of tropospheric ozone observed over Pohang, Korea

In this study, we present the analysis of vertical ozone sounding data observed over Pohang, Korea, and investigate to understand the governing mechanisms for seasonal ozone maximum in June. The vertical ozone profiles in June show that the ozone enhancement is clearly shown in the middle and upper troposphere. We have found that the June maximum is associated with the transport of ozone rich air from the stratosphere and polluted continental air mass. This is different from the previous studies shown that the regionally polluted continental air mass, influenced by the intense anthropogenic activities m northeast Asia during transport, is responsible for the ozone maximum in spring.