Marine aerosols were measured in real-time by an on-board signal particle aerosol mass spectrometer(SPAMS) over the Southeast China Sea. The chemical compositions and size distribution characteristics of aerosol particles were obtained, and the sources and ion spectra were analyzed. The results showed that particle number concentration decreased with the distance apart from the coastal area. In the coastal area, the aerosol compositions were mainly determined by the emissions of industry, such as vessel, traffic and coal combustion etc. When it was far from the continent, aerosols were mainly affected by the sea sources. Aerosol particles during the observation period disturbed singly with a peak diameter value of 0.5 μm. Most of the particles were in the size range of 0.2 μm to 0.8 μm. High signal intensity of EC with high K+ intensity in the positive spectrum and HSO4- intensity in negative spectrum was present in the marine aerosol over the coastal area. However, the signals of NO3- and NO2- were absent in the negative spectrum. The signal intensity of EC was weak in the marine aerosol over the sea area far from the coastal area. High signal intensity of Na+ and weak Mg+,Ca+ and NaCl+ signals were present in the positive spectrum, while high signal intensity of MSA-,CN-,O- and HSO4- were present in negative spectrum which was considered to be the special ions spectrum of marine biological sources. It indicated that ambient aerosols over the observation area were influenced not only by the anthropogenic emission sources but also affected by the marine aerosol formation.
Keywords: chemical compositions; marine aerosol; on-board observation; single particle aerosol mass spectrometer(SPAMS); size distribution.