A noticeable phenomenon of Asian dust particles during their trans-Pacific transport is that in cases where there is no precipitation, the mode diameters at different surface sites are approximately the same, about 3–4 microns for number distributions (particle number via particle size in per cubic unit of air) or a little larger for mass and volume distributions. This can be confirmed by comparing published data obtained in coastal areas of China, the Korean peninsula, Japanese islands, and the west coast of the United States.
While significant progress in the study of mineral dust particles in the atmosphere has been made, this phenomenon is not yet understood. Recent studies [e.g.,Zhang and Iwasaka, 2004] suggest that the interaction between dust particles and sea salt is a significant process involved in the changes of dust particles in size and composition in the marine boundary layer. This process can lead to the growth of dust particles and is likely responsible for the consistency of the mode diameters at different sites.