Relationship between air pollution and synoptic scale weather in South Korea

East Asia, including South Korea, has become a regional hot spot for the deteriorating air quality in recent years. During winter and spring, Particulate Matter (PM) is a dominant air pollutant. On the other hand, ozone becomes a major issue during summer season. In this talk, we’d like to show how synoptic scale weather pattern affects both PM and ozone in South Korea. Particularly, spatial synoptic classification (SSC) data are used to analyze characteristics of PM and ozone concentration according to synoptic weather patterns. During winter, dry moderate (DM) types occur frequently alongside high PM cases. The composite weather map showed a weak northwesterly wind field as a potential cause. On the contrary, it is interesting to note that dry polar (DP) types can be associated with low PM cases as well as high PM depending on near-surface wind speed. On the other hand, we found that DM, DT, and MT are commonly associated with high ozone; dry tropical (DT) produces ozone with the greatest efficiency, especially high levels of concentration. This finding implies a strong connection between surface ozone and climate change, because the occurrence of DT weather has increased by more three times over the past fifty years in South Korea.