New positive feedback mechanism between boundary layer meteorology and secondary aerosol formation during severe haze events.

ABSTRACT: Severe haze events during which particulate matter (PM) increases quickly from tens to hundreds of microgram per cubic meter in 1-2 days frequently occur in China. Although it has been known that PM is influenced by complex interplays among emissions, meteorology, and physical and chemical processes, specific mechanisms remain elusive. Here, a new positive feedback mechanism between planetary boundary layer (PBL), relative humidity (RH), and secondary PM (SPM) formation is proposed based on a comprehensive field experiment and model simulation. The decreased PBL associated with increased PM increases RH by weakening the vertical transport of water vapor; the increased RH in turn enhances the SPM formation through heterogeneous aqueous reactions, which further enhances PM, weakens solar rad

SUBMITTER: Liu Q 

PROVIDER: S-EPMC5904139 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature