HALOGENS IN AEROSOLS IN CENTRAL ALASKA

High volume filter samples were collected at Poker Flats in central Al aska, between 1984 and 1987, and analysed for a comprehensive suite of elements. In this report we focus on the results for the halogen elem ents Br, Cl and I, and their correlations with other selected elements (Al, As, Na, Se, and V). Seasonal cycles were observed for the haloge ns, including a pronounced spring peak in Br and a weak fall peak, pro nounced spring and fall peaks in I, and increased winter/spring Cl. A significant correlation between Br and Se was shown to be partly due t o common transport pathways, and possibly some common sources. Iodine showed enrichments of three orders of magnitude over sea water composi tion. Correlations to marine elements suggested a marine biogenic sour ce. Chlorine evidently originated from sea salt aerosols, but showed e vidence of substantial volatilization, correlated to the degree of pol lution of the air mass.