K. Matsumoto et al., SEASONAL CHARACTERISTICS OF ORGANIC AND INORGANIC SPECIES AND THEIR SIZE DISTRIBUTIONS IN ATMOSPHERIC AEROSOLS OVER THE NORTHWEST PACIFIC-OCEAN, Atmospheric environment, 32(11), 1998, pp. 1931-1946
In order to investigate the chemical properties of marine aerosols and
the long-distance transport of continental aerosols to remote oceanic
regions, simultaneous measurements of chemical compounds in atmospher
ic aerosols, cloud condensation nuclei (CCN) and associated species we
re conducted From December 1994 to January 1997 at Hahajima, the Ogasa
wara Islands, in the northwest Pacific Ocean, being located on the lee
of the large east Asian polluted region. Clear change of air quality,
caused by air mass alternation, are found. Concentrations of CCN and
aerosol chemical species, such as non-sea-salt sulfate, nitrate, and o
xalate, are low under the marine background conditions, whereas largel
y increased under the continentally affected conditions. It is ascerta
ined that long-distance transport of these species to the remote ocean
continues during half year periods. Seasonal characteristics and size
distributions of particulate organic acids, previously not well under
stood in earlier studies, are clarified. It is found that formate and
acetate could have marine biogenic sources, mostly existing as coarse
particles, whereas the oxalate was influenced by continental anthropog
enic activity, displaying a relative predominance in the accumulation
mode. (C) 1998 Elsevier Science Ltd. All rights reserved.