ELEMENTAL COMPOSITIONS OF INDIVIDUAL AEROSOL-PARTICLES COLLECTED OVERTHE SOUTHERN-OCEAN - A CASE-STUDY

Marine aerosols have been sampled from the boundary layer over the Sou thern Ocean. By means of X-ray spectrometry, elemental compositions of individual particles have been studied, The data reveal the occurrenc e of two chemical processes over the Southern Ocean: (1) modification of sea salts by acidic materials, where Cl- is replaced by SO42- and/o r NO3-, and (2) fractional recrystallization within evaporating seawat er drops followed by shattering. The effects of these phenomena appear to be simultaneously enhanced when there is mass transfer from the fr ee troposphere.