Characterizing role of particle-water in processing of biomass burning emissions and SOA formation
EMSL Project ID
51355
Abstract
Secondary organic aerosol (SOA) formed by multiphase chemical reactions in the atmosphere greatly contribute to fine particulate matter and organic aerosols (OA). Despite mounting evidence, aqueous- and cloud-phase SOA formation remains one of the least understood aspects of OA formation in the atmosphere [1-3]. The role of particle-phase water is, perhaps, the leading uncertainty in the evolution of moist biomass burning aerosols. This role can be considered to comprise of following key factors: (1) uptake of water vapor into the particle phase; (2) participation of water in facilitating particle phase separation; and (3) role of water in particle-phase chemistry. None of these three processes is sufficiently well understood currently to be predictive in the evolution and aging of biomass burning aerosols. The most challenging aspect is the role of water in particle-phase chemistry. The key science question that will be addressed in the proposed work is to determine the extent to which gas- and aqueous-phase chemistry involving water-soluble biomass burning volatile organic compounds (VOCs) leads to formation of highly oxidized products and SOA. To address this science question, we propose an integrated experimental and modeling study to unravel aqueous-phase processes of biomass-burning organic aerosols using a combination of unique EMSL analytical capabilities e.g. the single particle mass spectrometer (SPLAT), high resolution mass spectrometry (LTQ-Orbitrap-MS instruments) and microscopy techniques. Our study will help to elucidate how photooxidation of biomass burning VOCs under different humidity conditions and presence of aerosol-water changes SOA formation yields, and the physical and chemical processing of SOA (volatility, oxygen to carbon (O:C) ratio, oligomer content, and phase separation). We will derive the first direct measurements of kinetics of aqueous-biomass-burning-SOA formation and evolution of their properties for incorporation in modeling studies to understand how these highly uncertain aqueous-phase processes affect aerosol-cloud-radiation interactions in the atmosphere.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2020-10-01
End Date
N/A
Status
Active
Released Data Link
Team
Principal Investigator
Team Members