Volume 16, No. 12, December 2016, Pages 3130-3141 PDF(3.47 MB)
Supplementary MaterialPDF (205 KB)
Variability in Transport Pathways and Source Areas of PM10 in Beijing during 2009–2012
Dan Liang1, Yun-Qi Wang1,2, Chao Ma1, Yu-Jie Wang1,2
1 School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
2 Beijing Engineering Research Center of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
- Main source areas of PM10 are the south and southeast of Beijing.
- The northwest airflow is a key factor in extreme pollution episodes.
- It is urgent to reduce PM10 transport from areas surrounding Beijing.
The transport pathways and source areas of PM10 in Beijing were examined on the basis of a model-assisted analysis. Computed back trajectories were used to trace the air history. The aim of this work was to study the main source areas of PM10, the variability of transport pathways, and potential source areas in Beijing. The results reveal that the major potential source areas of PM10 in Beijing were Hebei, Shandong, Tianjin, northwest of Inner Mongolia, and Outer Mongolia. The main source areas of PM10 have changed from the northwest to the south and southeast of Beijing during 2009–2012. During the study period, the regional contributions of PM10 from Shandong, Tianjin and Henan increased, whereas those from Inner Mongolia and Mongolia decreased compared with 2003–2009. The northwest airflow is a key factor in extreme pollution episodes. Sand storm partly contributed to the PM10 concentration in fast northwesterly transport paths. PM10 concentrations in winter and spring were higher than autumn and summer. In spring and summer, Beijing was strongly affected by long-range transport. Long-range transport had a weaker effect on PM10 concentrations during autumn and winter. The clustering of back-trajectories and PSCF results indicate the need to reduce PM10 transport from areas surrounding Beijing, particularly from the south of Beijing.
PM10; Back trajectories; Regional sources; Extreme pollution episodes.