[A-CG44] Biogeochemical linkages between the surface ocean and atmosphere

[ACG44-06] Characterization of Adhesivity of marine organic aerosols by atomic force microscopy

*Kohei Ono¹, Ayumi Iwata², Takeshi Fukuma³, Yoko Iwamoto⁴, Koji Hamasaki⁵, Atsushi Matsuki⁶ (1.Graduate School of Natural Science and Technology, Kanazawa University, 2.Faculty of Science and Technology, Keio University, 3.Nano Life Science Institute, Kanazawa University, 4.Graduate School of Integrated Sciences for Life, Hiroshima University, 5.Atmosphere and Ocean Research Institute, The University of Tokyo, 6.Institute of Nature and Environmental Technology, Kanazawa University)

Keywords:Sea Spray Aerosol, Sea Foam, Atomic Force Microscopy (AFM), Adhesion Force, Deposition

Aerosol particles can trigger various environmental issues even after their deposition at the interface with the atmosphere. For example, sea spray aerosols (SSA) can deposit on the surfaces and cause corrosion of infrastructures such as electrical power cables and tower, as well as related polymer insulators especially in coastal areas. The adhesion force is the force by which aerosol particles continue to remain in contact with the deposition surface. The adhesion behavior of ambient aerosol particles is largely controlled by this force but has not earned enough attention. The aim of this study was to evaluate the physical property of SSA by measuring adhesion forces of simulated SSA on an individual particle basis using atomic force microscopy (force-distance curve mapping method). In order to simulate an organic enriched SSA, aerosols were generated using a bulk sea foam sample collected at Noto Peninsula during the Sea Surface Microlayer-Aerosol Project (SSMAP). The adhesion force of sea foam particles was compared with that of standard monosaccharide (glucose and fucose), artificial sea salt (ASS), as well as ambient SS particles. Mono saccharide particles showed significantly larger adhesion forces than ASS and SS. In addition, it was found that a few of sea foam particles and ambient SS particles showed similar adhesion forces and morphological features as the pure mono saccharides, suggesting that organic (e.g. mono saccharides) enriched SSA can be significantly more adhesive than the inorganic salts. Therefore, in the case of evaluating adhesive property of SSA, it is necessary to consider the presence of organics such as saccharides.