Study: Gases from burning biomass react within clouds, forming secondary organic aerosols

Phys.org  July 24, 2024
A team of researchers in the US (Pacific Northwest National Laboratory, UC Davis) developed a stand-alone box model to investigate four phenolic compounds, i.e., phenol, guaiacol, syringol, and guaiacyl acetone (GA), which represent some of the key potential sources of aqSOA from biomass burning in clouds. They predicted that the aqSOA formation potential (defined as aqSOA formed per unit dissolved organic gas concentration) of these phenols was higher than that of isoprene-epoxydiol (IEPOX), a well-known aqSOA precursor. Their simulations suggested that highly soluble and reactive multifunctional phenols like GA would predominantly undergo cloud chemistry within cloud layers, while gas-phase chemistry is likely to be more important for less soluble phenols. But in the absence of clouds, the condensation of low-volatility products dominates SOA formation, while the SOA formed through aqueous aerosol chemistry increases with relative humidity (RH). According to the researchers their model can be readily implemented in regional and global atmospheric chemistry models to investigate the aqueous aerosol and cloud chemistry of biomass-burning organic gases in the atmosphere… read more. TECHNICAL ARTICLE