Trace constituents in oceanic cloud water and their origin

Samples of oceanic cloud water collected during periods of varying rates of sea salt aerosol production have been analyzed for chloride, sodium, magnesium, calcium, and sulfate ions. For each of the ions, the portions originating from sea salt, chemical fractionation, and advected materials were calculated. Enrichment by chemical fractionation of sea salt was detected only in the case of magnesium. Considerable contributions of calcium and sulfate from origins other than sea salt were observed. Evidence indicates that excess chloride occurs erratically, and originates from volcanic activity.