Bursting bubbles inject inorganic and organic seawater constituents into the atmosphere.Because these nascent aerosols undergo rapid (seconds) multiphase chemical and physical transformation,it is difficult to differentiate primary versus secondary characteristics based on measurements in ambient marine air.We designed a 20-cm-diameter glass and Teflon model air-sea interface to generate primary marine aerosols and to investigate their physical and chemical properties and associated transformations.Fresh marine aerosols were generated by bubbling zero air through a 1.3-m column of flowing seawater with an overlying humidity-controlled headspace.Measured size distributions revealed two discrete,log-normally distributed modes.The centriod for the submicron mode ranged from ~80 to 145 nm for relative humidities ranging from 33 to 95%,respectively and its dry mass was dominated by organic carbon (OC).