Processes driving aerosol composition in the remote marine boundary layer

Abstract:

Arctic warming and decreasing sea ice extent are impacting atmospheric composition through changes in ocean-atmosphere interactions. Sea ice thinning and loss have complex, chemically and biologically mediated implications for aerosol and cloud properties, which are in part driven by aerosol source strengths and the relative contribution of primary and secondary aerosol sources in the marine boundary layer. Observations made during the NETCARE project in the Canadian High Arctic Archipelago provide evidence for frequent new particle formation and growth in the summertime marine boundary layer, driven by a combination of marine-derived sulfur, semi-volatile organic compounds, and amines. This talk will summarize airborne observations of aerosol composition, and highlight connections with surface-based observations and modelling efforts to understand aerosol sources in the Arctic marine boundary layer.

Field observations of these ambient aerosol systems motivate process level studies of multiphase atmospheric chemistry. This talk will also summarize laboratory studies of pH impacts on the rates and mechanisms of heterogeneous oxidation by ozone in aqueous aerosol.