A combination of experimental, molecular dynamics, and kinetics modeling
studies is applied to a system of concentrated aqueous sodium chloride
particles suspended in air at room temperature with ozone, irradiated
at 254 nanometers to generate hydroxide. Measurements of the observed
gaseous chlorine product are explainable only if reactions at the 
air-water interface are dominant. Molecular dynamics simulations show the 
availability of substantial amounts of chloride ions for reaction at the
interface, and quantum chemical calculations predict that in the gas phase
chloride ions will strongly attract hydroxide. Model extrapolation to the
marine boundary layer yields daytime chlorine atom concentrations that are
in good agreement with estimates based on field measurements of the decay
of selected organics over the Southern Ocean and the North Atlantic. Thus,
ion-enhanced interactions with gases at aqueous interfaces may play a more
generalized and important role in the chemistry of concentrated inorganic
salt solutions than was previously recognized.