We investigated the influence of long-range transboundary transport (LRTT) on the aerosol concentrations in the Korean peninsula using the ground- and satellite-based remote sensing with back-trajectory calculations during the Korea-United States Air Quality (KORUS-AQ) campaign. Specifically, aerosol optical depth (AOD) observations from a geostationary satellite can directly provide the progression and evolution of aerosol plume transport. During high pollution cases in western Korea, we found the AOD enhancement over the Yellow Sea and east-central China, at maximum >200% over the pathway of LRTT compared to the mean condition. Particularly, high AOD in the Shandong peninsula appears coincidentally with the high AOD over South Korea in a day, revealing the strong influence of the east-central Chinese emission. Back-trajectory patterns remarkably capture the movement of high AOD bands detected by the geostationary satellite monitoring. LRTT cases through the inside of boundary layer at east-central China usually contribute to the high AOD in Korea, while air-masses above the boundary layer in north China and Mongolia do not much relate to the Korean pollution, showing the importance for both the direction and height of the air-mass movement. Travel speed is another significant factor to describe the LRTT effect. Despite the large effect of LRTT to both urban and rural sites in Korea, sometimes urban sites are more affected by the domestic emission when the air-mass travels shorter than ∼250 km per day, notifying that the effect of Korean domestic emission cannot be negligible as well. Our findings reveal that usage of geostationary satellite observations enables us to better evaluate the influence of LRTT on the local air pollution.
Bibliographical noteFunding Information:
This subject was funded by Korea Ministry of Environment (MOE) as the Public Technology Program based on Environmental Policy (2017000160001). We thank all the AERONET principal investigators and their staff for establishing and maintaining the 19 AERONET sites used in this study. We also appreciate the contribution of Korea U.S.-Air Quality (KORUS-AQ) campaign ( https://doi.org/10.567/Suborbital/KORUSAQ/DATA01 ). We also thank the MODIS science team for providing valuable data for this research. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model and READY website ( http://www.ready.noaa.gov ) used in this publication. The authors would like to thank ECMWF and NCEP/NCAR for providing meteorological reanalysis data. MC's work was undertaken as a private enterprise and not in the author’s capacity as an employee of the Jet Propulsion Laboratory, California Institute of Technology.
© 2019 Elsevier Ltd
All Science Journal Classification (ASJC) codes
- Environmental Science(all)
- Atmospheric Science