State Key Laboratory of Severe Weather, Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing 100081, China.
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China.
Sci Total Environ. 2019 Feb 10;650(Pt 1):288-296. doi: 10.1016/j.scitotenv.2018.09.032. Epub 2018 Sep 4.
China suffers from high levels of PM pollution, which is often exacerbated by unfavorable planetary boundary layer (PBL) structures. Partly due to a lack of appropriate observations, the PBL-aerosol linkages in China are not clearly understood. Thus, we investigated these linkages from a national perspective using sounding data collected from 2014 to 2017. Correlation analyses revealed a significant anti-correlation between monthly boundary layer height (BLH) and aerosol pollution that was ubiquitous across China, indicating the important role of the PBL in regulating the seasonal variations of pollution in China. Besides, the day-to-day variations in pollution were modulated by the daily variabilities in the PBL structure. During winter, highly polluted days in most of the Chinese cities studied were associated with a low BLH, strong thermal stability, and weak PBL winds. In the North China Plain and Northeast China, the wintertime heavy pollution was often related to southerly winds and moister PBL. This study has important implications for understanding the crucial role that the PBL plays in modulating aerosol pollution in China.
中国遭受着高水平的 PM 污染，而这种污染往往因不利的行星边界层 (PBL) 结构而加剧。部分由于缺乏适当的观测，中国的 PBL-气溶胶联系还没有被清楚地理解。因此，我们使用 2014 年至 2017 年期间收集的探空数据，从全国范围的角度研究了这些联系。相关分析表明，在中国普遍存在的月度边界层高度 (BLH) 和大气污染之间存在显著的反相关关系，这表明 PBL 在调节中国污染的季节性变化方面发挥着重要作用。此外，污染的日变化受 PBL 结构的日变化调节。在冬季，中国大部分城市污染严重的日子与 BLH 低、热力稳定强和 PBL 风弱有关。在中国华北平原和东北地区，冬季的重度污染往往与南风和更潮湿的 PBL 有关。本研究对于理解 PBL 在调节中国气溶胶污染方面所起的关键作用具有重要意义。
