HIGH BROMINE AEROSOL CONCENTRATIONS NEAR LAKE HURON FROM LONG-RANGE TRANSPORT FROM THE ARCTIC DURING POLAR SUNRISE

Aerosol samples were collected at the Burnt Island sampling station in the northern part of Lake Huron, Canada. These samples were analyzed for trace elements via neutron activation analysis and aerosol concent rations were determined for the time period from 1992 through 1994. Th e seasonal trends of these aerosols were investigated and the results for bromine indicated seasonal highs in the month of March. This was d ifferent from the trend displayed by sodium whose peak was not as pron ounced. Sodium was an indicator of the salt component of the aerosol t hat Br was associated with at this site. Wind trajectory end-point ana lysis was utilized to show that the high Br aerosol concentrations ori ginate from the Arctic where Br aerosols have seasonal highs in the sp ring due to the photo-induced production of particulate Br. This resea rch shows that the highest levels of the Br aerosol in the rural north Lake Huron area originate from the production of Br in the Arctic.