Sullivan John T, McGee Thomas J, Stauffer Ryan M, Thompson Anne M, Weinheimer Andrew, Knote Christoph, Janz Scott, Wisthaler Armin, Long Russell, Szykman James, Park Jinsoo, Lee Youngjae, Kim Saewung, Jeong Daun, Sanchez Dianne, Twigg Laurence, Sumnicht Grant, Knepp Travis, Schroeder Jason R
Atmospheric Chemistry and Dynamics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, 20771, USA.
Universities Space Research Association, Columbia, MD, 21046, USA.
Atmos Chem Phys. 2019;19(7):5051-5067. doi: 10.5194/acp-19-5051-2019.
During the May-June 2016 International Cooperative Air Quality Field Study in Korea (KORUS-AQ), light synoptic meteorological forcing facilitated Seoul metropolitan pollution outflow to reach the remote Taehwa Research Forest (TRF) site and cause regulatory exceedances of ozone on 24 days. Two of these severe pollution events are thoroughly examined. The first, occurring on 17 May 2016, tracks transboundary pollution transport exiting eastern China and the Yellow Sea, traversing the Seoul Metropolitan Area (SMA), and then reaching TRF in the afternoon hours with severely polluted conditions. This case study indicates that although outflow from China and the Yellow Sea were elevated with respect to chemically unperturbed conditions, the regulatory exceedance at TRF was directly linked in time, space, and altitude to urban Seoul emissions. The second case studied, occurring on 09 June 2016, reveals that increased levels of biogenic emissions, in combination with amplified urban emissions, were associated with severe levels of pollutions and a regulatory exceedance at TRF. In summary, domestic emissions may be causing more pollution than by trans-boundary pathways, which have been historically believed to be the major source of air pollution in South Korea. The case studies are assessed with multiple aircraft, model (photochemical and meteorological) simulations, in-situ chemical sampling, and extensive ground-based profiling at TRF. These observations clearly identify TRF and the surrounding rural communities as receptor sites for severe pollution events associated with Seoul outflow, which will result in long-term negative effects to both human health and agriculture in the affected areas.
在2016年5月至6月于韩国开展的国际合作空气质量实地研究（KORUS-AQ）期间，微弱的天气尺度气象强迫促使首尔都市圈的污染物外流至偏远的太白山研究林（TRF）站点，并导致该站点24天出现臭氧超标情况。其中两次严重污染事件得到了全面研究。第一次事件发生在2016年5月17日，追踪到来自中国东部和黄海的跨界污染传输，穿过首尔都市圈（SMA），然后在下午时分以严重污染的状况抵达TRF。该案例研究表明，尽管与化学未受扰动的情况相比，来自中国和黄海的外流污染物有所增加，但TRF的监管超标情况在时间、空间和高度上与首尔市区的排放直接相关。所研究的第二个案例发生在2016年6月9日，结果显示生物源排放的增加，再加上城市排放的放大，与TRF的严重污染水平和监管超标情况有关。总之，国内排放可能比跨界路径造成了更多污染，而跨界路径在历史上一直被认为是韩国空气污染的主要来源。通过多架飞机、模型（光化学和气象）模拟、现场化学采样以及在TRF进行的广泛地面剖面测量对这些案例进行了评估。这些观测结果清楚地表明，TRF及周边农村社区是与首尔外流相关的严重污染事件的受体站点，这将对受影响地区的人类健康和农业产生长期负面影响。
