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ON THE ORIGIN AND TRANSPORT OF THE WINTER ARCTIC AEROSOL *

Results of a systematic study of the winter aerosol at Barrow, Alaska, are presented which show that the atmosphere of arctic Alaska contains an abundance of pollution-derived aerosol, particularly during the winter half-year, and that Europe, rather than the U.S., appears to be primarily responsible for the winter arctic aerosol. It is found that the aerosol is an order of magnitude more concentrated in winter than in summer throughout most of the troposphere, is gray in winter but colorless in summer, is much more enriched in pollution-derived constituents (such as V, Mu, and SO/sub 4/) in winter than in summer, and appears to be highly secondary in nature. A simple transport model is described, and it is demonstrated that the actual concentrations of V, SO/sub 4/, and Pb-210 at Barrow are quantitatively consistent with polluted European air masses as the source, followed by transport over the European USSR and then to the north.