11:30 AM - 11:45 AM
[ACG52-10] Linkages between atmospheric organic aerosols and surface seawater during phytoplankton blooms in spring
Keywords:Atmospheric organic aerosols, Phytoplankton bloom, Biogeochemical linkage between atmosphere and ocean
Observational study during the R/V Hakuho-maru cruise from March 6 to 26, 2015, investigated the contribution of microbial activity in surface seawater to the formation of atmospheric organic aerosols by direct comparison of chemical/biogeochemical characteristics of organics aerosol with those of particulate/dissolved organics in surface seawater. On average, organics accounted for the majority (~40%) of the submicron particle mass, which was attributable to dissolved organic carbon (DOC) and particulate organic carbon (POC) in the sea surface based on the measurement of stable carbon isotopic ratios of water-soluble organic carbon (WSOC) aerosols (δ13CWSOC). We present a general overview of atmospheric observations during the cruise and discuss (1) chemical characterization of ocean-derived submicron WSOC compared with biogeochemical characterization of DOC measured by excitation emission matrix (EEM) fluorescence, and (2) comparison between organic aerosol mass and the fraction of POC linked to the development/aging of diatom bloom.