Sources of black carbon during severe haze events in the Beijing-Tianjin-Hebei region using the adjoint method

Yu-Hao Mao; Xincheng Zhao; Hong Liao; Delong Zhao; Ping Tian; Daven K Henze; Hansen Cao; Lin Zhang; Jiandong Li; Jing Li; Liang Ran; Qiang Zhang

doi:10.1016/j.scitotenv.2020.140149

Sources of black carbon during severe haze events in the Beijing-Tianjin-Hebei region using the adjoint method

Sci Total Environ. 2020 Oct 20:740:140149. doi: 10.1016/j.scitotenv.2020.140149. Epub 2020 Jun 11.

Authors

Yu-Hao Mao¹, Xincheng Zhao², Hong Liao³, Delong Zhao⁴, Ping Tian⁴, Daven K Henze⁵, Hansen Cao⁵, Lin Zhang⁶, Jiandong Li², Jing Li⁶, Liang Ran⁷, Qiang Zhang⁸

Affiliations

¹ Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control/Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology (NUIST), Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/International Joint Research Laboratory on Climate and Environment Change (ILCEC), NUIST, Nanjing 210044, China. Electronic address: yhmao@nuist.edu.cn.
² Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control/Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology (NUIST), Nanjing 210044, China.
³ Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control/Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology (NUIST), Nanjing 210044, China; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/International Joint Research Laboratory on Climate and Environment Change (ILCEC), NUIST, Nanjing 210044, China.
⁴ Beijing Weather Modification Office, Beijing 100089, China.
⁵ Department of Mechanical Engineering, University of Colorado, Boulder, CO 80309, USA.
⁶ Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100081, China.
⁷ Key Laboratory of Middle Atmosphere and global Environment Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; Xianghe Observatory of Whole Atmosphere, Institute of Atmospheric Physics, Chinese Academy of Sciences, Xianghe 065400, China.
⁸ Ministry of Education Key Laboratory for Earth System Modeling, Center for Earth System Science, Tsinghua University, Beijing 100084, China.

PMID: 32563001
DOI: 10.1016/j.scitotenv.2020.140149

Abstract

The Beijing-Tianjin-Hebei (BTH) region in China has been frequently suffering from severe haze events (observed daily mean surface fine particulate matter PM_2.5 concentrations larger than 150 μg m^-3) partially caused by certain types of large-scale synoptic patterns. Black carbon (BC), as an important PM_2.5 component and a primarily emitted species, is a good tracer for investigating sources and formation mechanisms leading to severe haze pollutions. We apply GEOS-Chem model and its adjoint to quantify the source contributions to BC concentrations at the surface and at the top of the planetary boundary layer (PBL) during typical types of severe haze events for April 2013-2017 in BTH. Four types of severe haze events, mainly occurred in December-January-February (DJF, 62.3%) and in September-October-November (SON, 26.3%), are classified based on the associated synoptic weather patterns using principal component analysis. Model results reasonably capture the daily variations of BC measurements at three ground sites in BTH. The adjoint method attributes BC concentrations to emissions from different source sectors and from local versus regional transport at the model spatial and temporal resolutions. By source sectors, the adjoint method attributes the daily BC concentrations during typical severe haze events (in winter heating season) in Beijing largely to residential emissions (48.1-62.0%), followed by transportation (16.8-25.9%) and industry (19.1-29.5%) sectors. In terms of regionally aggregated source influences, local emissions in Beijing (59.6-79.5%) predominate the daily surface BC concentrations, while contributions of emissions from Beijing, Hebei, and outside BTH regions are comparable to the daily BC concentrations at the top of PBL (~200-400 m). Our adjoint analyses would provide a scientific support for joint regional and targeted control policies on effectively mitigating the particulate pollutions when the dominant synoptic weather patterns are predicted.

Keywords: Adjoint method; Black carbon; Severe particulate pollution in China; Source attribution; Synoptic weather patterns.