M. Uematsu et al., Scavenging of insoluble particles from the marine atmosphere over the sub-Arctic North Pacific, J ATMOS CH, 35(2), 1999, pp. 151-164
Direct deposition measurements of atmospheric insoluble particles over the
sub-Arctic North Pacific indicate that the number of particles (6.4 +/- 3.8
) x 10(4) cm(-2) per rain event was fairly constant compared with the large
variation of the precipitation rate, which ranged from 0.16 to 18 mm per e
vent for 43 rain days during the period of March-September (total 109 days)
1996. This suggests that insoluble particles larger than 0.4 mu m in area
equivalent diameter are primarily removed at the margin of the rainfall are
a by wet scavenging processes below clouds in the marine atmosphere in sub-
Arctic regions. The frequency of rain events controls the fate of the tropo
spheric aerosols larger than sub-micrometer in diameter. Reflecting the sea
sonal long-range transport of Asian dust, mineral particles were dominant a
s insoluble particles in the spring rains, but carbonaceous particles were
dominant in the summer rains. The atmospheric deposition of insoluble parti
cles could be significant as a source of sediment particles over the sub-Ar
ctic North Pacific.