Massive air pollutants originating in China and their trans-boundary transports are an international concern in East Asia. Despite its importance, details in the trans-boundary transport of air pollutants over East Asia and its impact on regional air quality remain to be clarified. This study presents an evidence which strong support that aerosols emitting in China play a major role in the occurrence of multi-day (≥4 days) severe air pollution episodes in cold seasons (October through March) for 2001-2013 in Seoul, Korea, where the concentration of PM10 (particulates with diameters≤10μm) exceeds 100μgm-3. Observations show that these multi-day severe air pollution episodes occur when a strong high-pressure system resides over the eastern China-Korea region. In such weather conditions, air pollutants emitted in eastern China/southwestern Manchuria are trapped within the atmospheric boundary layer, and gradually spread into neighboring countries by weak lower tropospheric westerlies. Understanding of trans-boundary transports of air pollutants will advance the predictability of local air quality, and will encourage the development of international measures to improve air quality.
Bibliographical noteFunding Information:
This work was funded by the Korea Ministry of Environment as ‘Climate Change Correspondence R&D Program’. Yong-Sang Choi was supported by the Korean Ministry of Environment as part of the Eco-Innovation Project. The funders had no role in the study design, data collection and analysis, decision to publish, or presentation of the manuscript. The authors wish to thank for Mrs. Chun Hee Jeoung for her assistance in data handling at the initial stages of our work. The authors are appreciative of helpful comments by two reviewers.
© 2015 Elsevier Ltd.
- PM episode
- Trans-boundary transport