Understanding the underlying mechanisms governing the linkage between atmospheric oxidative capacity and ozone precursor sensitivity in the Yangtze River Delta, China: A multi-tool ensemble analysis

Kaihui Zhao; Yonghua Wu; Zibing Yuan; Jianping Huang; Xuehui Liu; Wei Ma; Danni Xu; Rongsheng Jiang; Yusen Duan; Qingyan Fu; Wei Xu

doi:10.1016/j.envint.2021.107060

Understanding the underlying mechanisms governing the linkage between atmospheric oxidative capacity and ozone precursor sensitivity in the Yangtze River Delta, China: A multi-tool ensemble analysis

Environ Int. 2022 Feb:160:107060. doi: 10.1016/j.envint.2021.107060. Epub 2021 Dec 21.

Authors

Kaihui Zhao¹, Yonghua Wu², Zibing Yuan³, Jianping Huang⁴, Xuehui Liu¹, Wei Ma¹, Danni Xu¹, Rongsheng Jiang⁵, Yusen Duan⁶, Qingyan Fu⁶, Wei Xu⁷

Affiliations

¹ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
² The City College of New York (CCNY), New York, NY 10031, USA; NOAA-Cooperative Science Center for Earth System Sciences and Remote Sensing Technologies, New York, NY 10031, USA.
³ School of Environment and Energy, South China University of Technology, Guangzhou 510006, China. Electronic address: zibing@scut.edu.cn.
⁴ NOAA-NCEP Environmental Modeling Center and IM System Group Inc., College Park, MD 720740, USA; Yale-NUIST Center on Atmospheric Environment, Nanjing University of Information Science & Technology, Nanjing 210044, China.
⁵ Jiangsu Meteorological Service Center, Nanjing 210008, China.
⁶ Shanghai Environmental Monitoring Center, Shanghai 200235, China.
⁷ Xianyang Meteorological Bureau, Xianyang 712000, China.

PMID: 34952358
DOI: 10.1016/j.envint.2021.107060

Abstract

Continued exacerbation of ozone (O₃) pollution in China has driven the urgent need for an emission control strategy that efficiently reduces O₃ levels. Determining O₃ precursor sensitivity (OPS) and its driving factors is a prerequisite for formulating effective O₃ control strategies. In this study, we proposed an atmospheric oxidative capacity-based indicator, HO₂/OH, and demonstrated its effectiveness in indicating OPS over the Yangtze River Delta (YRD) of China by applying a localized comprehensive air quality model with extensions (CAMx) coupled with the Weather Research and Forecasting (WRF) model. A strong correlation was discovered between HO₂/OH and OPS, and HO₂/OH showed the best performance in separating NO_x- and VOC-limited regimes in comparison with other commonly used indicators. A comprehensive analysis with ensemble diagnostic tools revealed the spatial heterogeneity of NO_x and VOC emissions and the impact of regional transport controlling the relationship between OPS variations and the HO₂/OH indicator over the YRD. The process analysis results show that days with higher contributions from horizontal advection favored OPS transitions in Shanghai, Nanjing, Hefei, Suzhou, and Wuhu, while vertical advection caused OPS transitions in Hangzhou and Ningbo. O₃ source apportionment technology analysis indicated that the regional contributions from Zhejiang and Jiangsu/Anhui corresponded well to the NO_x-limited and VOC-limited regimes, respectively. Our results provide a better understanding of the underlying mechanisms of the relationship between OPS and the HO₂/OH indicator and can help guide contingency control measures for O₃ despiking over the YRD and other photochemically active regions worldwide.

Keywords: HO(2)/OH; Ozone pollution; Photochemical indicator; WRF-CAMx; Yangtze River Delta.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Air Pollutants* / analysis
Air Pollution* / analysis
China
Environmental Monitoring
Oxidative Stress
Ozone* / analysis
Rivers
Seasons

Substances

Air Pollutants
Ozone