SPATIAL AND TEMPORAL VARIATION OF POLYCYCLIC AROMATIC-HYDROCARBONS INTHE ARCTIC ATMOSPHERE

In the first multi-year arctic air sampling program, PAI-ls were sampl ed (vapor and particulate) every week at three locations in the Canadi an and Russian Arctic. Data are presented here for the years 1992-1994 . The geometric mean Sigma PAH concentrations (where Sigma=16 compound s) for 1993 ranged from 249 to 508 pg/m(3) for the three sites. Clear seasonality was evident with the highest concentrations occurring duri ng the colder months of October-April, coinciding with the arctic haze period. PAH concentrations during this period were highest in the ord er of Dunai (Russian) > Alert (high Arctic) > Tagish (Pacific). Air ma ss back trajectories computed for February 1994 revealed long-range tr ansport from Eurasia into the high Arctic. Short periods of high conce ntrations were also evident during the warmer months, most notably at the Tagish site, where elevated levels of retene (a marker for soft wo od combustion) matched forest fire records. Initial findings suggest t hat the gas/particle partitioning of some of the lighter PAHs, examine d during the colder haze period, is similar to remote temperate studie s and in reasonable agreement to the Junge-Pankow adsorption model.