Seasonal changes in pollutant transport to the North Pacific: the relative importance of Asian and European sources.

The industrialization of south-east Asia invokes interest in the export path of the associated pollution into the global atmosphere. During the winter the meteorology of this area is dominated by the Siberian anticyclone. Polluted air is typically kept in the planetary boundary layer by the large-scale subsidence and moved southwards. This contrasts with the summer when it can be lifted to the upper troposphere and transported across the Pacific by the aloft. This seasonal variation is investigated using trajectory calculations. Then the influence of pollution from the. European region on south-east Asia is investigated. During the winter up to 40% of the tropospheric air entering south-east Asia may have been polluted by Europe. Finally, we propose an extended monitoring program over central Asia to separate south-east Asian pollution from the general pollution found in the Northern Hemisphere, and, to understand the effects of this industrialization.