Abstract
Assessment of spatial distribution and variation of optical properties and chemical species in atmospheric aerosols is essential to estimate the direct climate forcing. In the western North Pacific, where pollutants are transported from the East Asia, there are few aerosol measurements available to estimate the climate forcing. In this study the aerosol optical and chemical properties were measured during June-July 2000 (MR00-K04 cruise) and May 2001 (MR01-K02 cruise) in the western North Pacific on board the research vessel Mirai during the ACE-Asia campaign. During MR00-K04 cruise, in the southern area of 30°N, it was found that the area was under marine background condition. The single scattering albedo (ω) ranged from 0.95 to 0.99. On the other hand, during MR01-K02 cruise, it was found that anthropogenic aerosols and soil particles originating from the Asian Continent were transported. Then, the ω ranged from 0.82 to 0.95 were measured, which were absorptive aerosols.