Size Distributions of Atmospheric Aerosols in Kitakyushu City, from 1974 to 1976

Abstract

Mass-size distributions of atmospheric aerosols in Kitakyushu city were measured by use of Andersen sampler, and their trends in past three years (1974-1976) were investigated. The results showed that the distributions of aerosols are divided near 1-2μm into two groups, coarse and fine particles, regardless of sampling stations, seasons or years. Since differences in total aerosol concentration among sampling stations are due mainly to particles larger than 1μm (coarse particles), this particles are considered to begenerated artificially. For seasonal variations, the concentration of the coarse particles at the reference station also tends to increase in spring.
Therefore, different meteorological conditions and natural phenomena in addition to artificial sources may take part in an increase of the coarse particles. The division of the aerosols into two groups implies that the coarse and fine particles differ in their sources, formation mechanisms and removal processes.