Iodine, bromine, and chlorine in winter aerosols and snow from Barrow, Alaska

Abstract

Iodine, bromine, and chlorine have been determined in atmospheric aerosols and in snow collected in Barrow, Alaska, during January, 1965, by means of neutron activation analysis. Aerosols collected using both an aircraft collector by impaction and a ground-based 1. 0 , ~ Type EA Millipore filter collector show concentrations of C1 to be much more variable than either Br or I, and I/Br points cluster at 0.1-0.2 gI/gBr for the filter samples. C1 varies from <0.02 to 4 pg Cl/m$STP in the filter samples, and the aircraft concentrations agree with those taken by filter on the same days. Filter Br is 1-30 ngBr/mSSTP and I is 0.3-10 ngI/m3STP, and the ratios I/Cl and Br/CI increase sharply with decreasing C1. Snow samples from the ground have Br/CI somewhat greater than in sea water, although all halogen concentrations decrease with increasing distance from the sea up to 10 km. Assuming a mixture of undifferentiated sea salt and a more permanent atmospheric component, we estimate for the atmospheric component in the snows I/Br=0.2. Sea water, sea ice, and related samples were analyzed, and I/C1=4 x 10-6 gI/gCI is normal for sea water, although Br/C1= 3.8 x gBr/gCl stands a little high.