The impact of mixing states on the physical properties of atmospheric aerosols: Cases from individual particle analyses on sea spray aerosols

Abstract

Sea spray aerosols (SSA) are generated when sea spray is released into the atmosphere through the bursting of bubbles caused by strong winds and breaking waves. Conventionally, SSA has been considered to consist mainly of inorganic salts derived from seawater, such as NaCl and MgCl₂. However, recent studies have highlighted that the sea-surface microlayer (SML), which includes marine microorganisms and their exudates, plays a crucial role in the formation of SSA enriched in organic matter, thus significantly altering the morphology and composition of SSA. The physical properties and the proportion of diverse organic substances derived from SML present in individual particles may result in atmospheric behavior that is markedly different from SSA composed solely of inorganic salts. In this presentation, we focus on the mixing state at the individual particle level and introduce several case studies evaluating the impact of organic matter on the physical properties of SSA.