Characterization of atmospheric aerosols and of suspended particles in seawater in the western Pacific Ocean

Aerosol samples were collected to study the variabilities of marine aerosols at different times and in different ocean areas. The samples were collected during the first three cruises (December 12, 1985, to February 21, 1986; November 11, 1986, to March 1, 1987; September 27 to November 4, 1987) operated by the cooperative program between the United States and the People's Republic of China. The concentrations of crustal and pollution elements in aerosols were high over the ocean area close to the China coast and decreased very rapidly with increasing distance from land. For the third cruise, in the ocean area northeast of the Philippines, the concentrations of crustal and pollution elements in aerosols were high, especially Fe, whose values reached 3.15 × 10−5 g m−3. For all three cruises, the mass size distributions of crustal elements and pollution elements in aerosols showed more large particles. The morphology and elemental composition of aerosol particles showed that sea‐salt particles may conglomerate with small crustal and pollution particles from land to form large particles. The size distributions of suspended particles (d > 0.3 μm) in surface seawater approximately fitted the Junge size distribution. The concentration of suspended particles in surface seawater decreased with increasing distance from land except at the equator, where particle concentrations were high. In addition, results from rain chemistry show that the relative importance between wet deposition and dry deposition varies with trace elements.