FORURENS: Occurence and fate of springtime atmospheric deposition of mercury in the Arctic

Deposition of mercury (Hg) from the atmosphere to the sensitive polar ecosystems is of particular interest in the Arctic. This is because studies have indicated the possibility of large depositional fluxes of Hg occurring during the polar spring (so-calle d Hg Atmospheric Depletion Events or AMDEs. While the ecological importance of AMDEs in cold environments is now accepted by the scientific community, several uncertainties remain in our understanding of the AMDE phenomenon. Through several field campai gns at Ny-Ålesund during spring and summer, this study will provide data to assess how much mercury is transported to the Arctic by the air and how much falls on the snow/ground. The project will also contribute to the understanding of the chemical and p hysical processess of AMDE, as well as contribute towards a possible future warning system for atmospheric mercury deposition episodes on the basis of operationally available meteorological data.