1 Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), Joint International Research Laboratory of Climate and Environment Change (ILCEC), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing, Jiangsu 210044, China
2 Qianshan Meteorological Bureau, Anqing, Anhui 246300, China
3 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
Cite this article: Zhang, Y., Zhu, B., Gao, J., Kang, H., Yang, P., Wang, L. and Zhang, J. (2017). The Source Apportionment of Primary PM2.5 in an Aerosol Pollution Event over Beijing-Tianjin-Hebei Region using WRF-Chem, China.
Aerosol Air Qual. Res.
17: 2966-2980. https://doi.org/10.4209/aaqr.2016.10.0442
We coupled the WRF-Chem model with a primary PM2.5 source-apportionment method.
We effectively simulated a severe haze episode in the Beijing-Tianjin-Hebei region.
Synoptic conditions, terrain, and the boundary layer contributed to PM2.5 levels.
Significant pollution moved into the region via long-distance transport.
The Weather Research and Forecasting model coupled to Chemistry (WRF-Chem model) was modified with an online primary PM2.5 source-apportionment method to simulate a severe aerosol pollution episode that occurred over the Beijing-Tianjin-Hebei (BTH) region of China from October 29 to November 8, 2015. The temporal and spatial distributions and transport characteristics of this episode were examined, and the quantified primary PM2.5 contributions by various geographical source regions to the BTH region were also analyzed in this study. The results showed that pollution in this region was mainly due to the combined effects of the synoptic conditions, terrain, and boundary layer characteristics. Before the heavy pollution event, the most parts of the BTH region were controlled by northwest wind, and the local primary PM2.5 contribution to the BTH region accounted for 90.7%. During the heavy pollution period, the BTH region was under isobaric synoptic conditions with light horizontal winds and a stable temperature stratification structure and a lower PBLH, allowing pollutants to accumulate easily in the region. Large quantities of pollutants were transported to the BTH region from Shandong, Jiangsu, Anhui, and Henan provinces via the southerly wind, accounting for 11.6%, 9.2%, 6.7%, 11.8%, respectively. Furthermore, pollutants accumulated more significantly under a stable boundary layer structure and the northwest-southeast terrain structure. Therefore, regional contributions increased, and other polluted areas, especially the long-distance transport from a source in the Yangtze River Delta city group region, contributed about 15.9%. It should be noted that the percentage of primary PM2.5 within the total PM2.5 in the study period almost exceeded 50%, and in the BTH region nearly surpassed 60%. To a certain extent, primary PM2.5 can help characterize total PM2.5.