Secondary aerosol formation in winter haze over the Beijing-Tianjin-Hebei Region, China
- PDF / 587,580 Bytes
- 13 Pages / 595.276 x 785.197 pts Page_size
- 1 Downloads / 142 Views
REVIEW ARTICLE
Secondary aerosol formation in winter haze over the BeijingTianjin-Hebei Region, China Dongjie Shang1, Jianfei Peng2, Song Guo1, Zhijun Wu1, Min Hu (✉)1,3 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China 2 Department of Atmospheric Sciences, Texas A&M University, College Station, TX 77843, USA 3 Beijing Innovation Center for Engineering Sciences and Advanced Technology, Peking University, Beijing 100871, China
HIGHLIGHTS
GRAPHIC ABSTRACT
• Characteristics and interannual variation of aerosol pollution are illustrated. • Mechanisms of secondary aerosol formation in winter haze of North China are reviewed. • Directions in future studies of secondary aerosol formation are provided.
ARTICLE INFO Article history:
Received 15 April 2020 Revised 14 August 2020 Accepted 17 August 2020 Available online 8 October 2020 Keywords: Secondary aerosol formation Regional haze Photochemical reaction Aqueous reaction Chemical mechanism
ABSTRACT Severe haze pollution occurs frequently in the winter over the Beijing-Tianjin-Hebei (BTH) region (China), exerting profound impacts on air quality, visibility, and human health. The Chinese Government has taken strict mitigation actions since 2013 and has achieved a significant reduction in the annual mean PM2.5 concentration over this region. However, the level of secondary aerosols during heavy haze episodes showed little decrease during this period. During heavy haze episodes, the concentrations of secondary aerosol components, including sulfate, nitrate and secondary organics, in aerosol particles increase sharply, acting as the main contributors to aerosol pollution. To achieve effective control of particle pollution in the BTH region, the precise and complete secondary aerosol formation mechanisms have been investigated, and advances have been made about the mechanisms of gas phase reaction, nucleation and heterogeneous reactions in forming secondary aerosols. This paper reviews the research progress in aerosol chemistry during haze pollution episodes in the BTH region, lays out the challenges in haze formation studies, and provides implications and directions for future research. © Higher Education Press 2020
1
Introduction
Severe regional haze pollution, characterized by rapid increases of fine particulate matter (PM2.5) in the atmosphere (Liu et al., 2013), occurred frequently in winter over the Beijing-Tianjin-Hebei (BTH) region (China) in recent years, leading to serious visibility degradation and exerting
✉ Corresponding author E-mail: [email protected]
profound negative impacts on human health (Pöschl, 2005; Chen et al., 2013; Cao et al., 2014). Severe haze events usually occurred with extensive temporal and spatial coverage in the BTH region (Sun et al., 2016a). For example, in January 2013, a continuous and large scale haze event spread over more than 1 million km2 in Northern China with extraordinarily high PM2.5 concentrations (hou
Data Loading...
