Mercury in Arctic air: The long-term trend

The long-term (1974–2000) time trend of total filterable mercury (TFM) in the air in the Canadian Arctic is reported. The concentration of TFM had declined by (3.0 ± 0.8) % and (3.1 ± 0.9) % per year in the summer and fall, respectively, over the 27 years, which coincided with the calculated reduction rate of world-wide mercury emission (~ 3.3% per year) from human activities between 1983 and 1995. The time trend for winter and early spring was not statistically significant as the variability of TFM was very large, partly due to Arctic Mercury Depletion Events and partly due to Arctic haze.