CHEMICAL COMPOSITION OF KOSA AEROSOL (YELLOW SAND DUST) COLLECTED IN JAPAN

Abstract

Typical Kosa aerosol was simultaneously collected at several sampling sites in Japan, during spring, 1988. After the sample was separated for water soluble fraction and insoluble fraction, many elements and ions in both fractions were determined by ICP-AES and IC. The higher atmospheric concentrations of crustal elements and NO₃^- and Non-sea-salt(nss)SO₄^2- were measured in Kosa aerosol than those in non-Kosa aerosol. It can be estimated the surface deposition of NO₃^- and nssSO₄^2- during transport to Japan from Chinese arid areas, because of the difference of the concentration ratios against Al in the Kosa aerosol at two remote sampling sites. Though Kosa aerosol is expected to act as a carrier of acidic materials, its alkaline nature may help to mitigate the damage of acid rain in Japan.