AbstractIt was discovered in 1995 that, during the spring time, unexpectedly low concentrations of gaseous elemental
mercury (GEM) occurred in the Arctic air. This was surprising for a pollutant known to have a long residence time in the atmosphere; however conditions appeared to exist
in the Arctic that promoted this depletion of mercury (Hg).
This phenomenon is termed atmospheric mercury depletion
events (AMDEs) and its discovery has revolutionized our understanding of the cycling of Hg in Polar Regions while stimulating a significant amount of research to understand its
impact to this fragile ecosystem. Shortly after the discovery
was made in Canada, AMDEs were confirmed to occur
throughout the Arctic, sub-Artic and Antarctic coasts.