Evaluation of regional transport of PM2.5 during severe atmospheric pollution episodes in the western Yangtze River Delta, China. (1st September 2021)

• Record Type: Journal Article
• Authors: Sulaymon, Ishaq Dimeji; Zhang, Yuanxun; Hu, Jianlin; Hopke, Philip K.; Zhang, Yang; Zhao, Bin; Xing, Jia; Li, Lin; Mei, Xiaodong
• Is Part Of: Journal of environmental management. Volume 293(2021)
• Publication Date: 2021-09-01
• Subjects: PM2.5 flux -- Regional transport -- Atmospheric pollution episodes -- WRF-CMAQ -- Anhui province; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2021.112827
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: During winter 2018, the 16 prefecture-level cities in Anhui Province, Western Yangtze River Delta region, China had very high PM2.5 concentrations and prolonged pollution days. The impact of regional transport in the formation, accumulation, as well as dispersion of fine particulate matter (PM2.5 ) in Anhui Province was very significant. This study quantified and analyzed the vertical transport of PM2.5 in three major cities (Hefei, Fuyang, and Suzhou) of Anhui Province in January and July 2018 using the Weather Research and Forecasting (WRF) model coupled with the Community Multiscale Air Quality (CMAQ) model. The results of the inter-regional transport of PM2.5 revealed the dominant transport pathways for the three cities. The flux mainly flowed into Fuyang from Henan (2.23 and 1.42 kt/day in January and July, respectively) and Bozhou (1.96 and 1.21 kt/day in January and July, respectively), while the main flux from Fuyang flowed into Henan (−2.15 kt/day) and Lu'an (−1.91 kt/day) in January and Henan (−0.34 kt/day) and Bozhou (−0.29 kt/day) in July. In addition, the dominant transport pathways and the heights at which they occurred were identified: the northwest-southeast and northeast-south pathways in both winter and summer at both lower (˂300 m) and higher (≥300 m) levels for Fuyang; the northwest-south and northeast-southwest pathways in winter (at both lower and upper levels) and northwest-east and northeast-southwest pathways in summer at lower and upper levels for Hefei; and the northwest-southeast and northeast-south pathways in both winter (from 50 m up to the top level) and summer (between 100 and 300 m) for Suzhou. Furthermore, the intensities of daily PM2.5 transport fluxes in Fuyang during the atmospheric pollution episode (APE1) were stronger than the monthly average. These results show that joint emission controls across multiple cities along the identified pathways are urgently needed to reduce winter episodes. Graphical abstract: Image 1 Highlights: Anhui province had severe PM2.5 pollution during winter 2018. Fuyang and Hefei acted as the source of PM2.5 in winter. Regional transport was a major influence on PM2.5 pollution in Anhui. Major transport pathways and the heights at which they occurred were identified. Control of upstream sources could reduce PM2.5 and provide better air quality.