Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 4 9/10 2004 10.5194/acp-4-2251-2004 http://www.atmos-chem-phys.net/4/2251/2004/ http://www.atmos-chem-phys.net/4/2251/2004/acp-4-2251-2004.html http://www.atmos-chem-phys.net/4/2251/2004/acp-4-2251-2004.pdf 2251 2257 2004-11-22 Modelling of Mercury in the Arctic with the Danish Eulerian Hemispheric Model J. H. Christensen J. Brandt L. M. Frohn H. Skov National Environmental Research Institute, Frederiksborgvej 399, 4000 Roskilde, Denmark A new 3-D mercury model has been developed within the Danish Arctic Monitoring and Assessment Programme (AMAP). The model is based on the Danish Eulerian Hemispheric Model, which in the original version has been used to study the transport of SO₂, SO₄^2- and Pb into the Arctic. It was developed for sulphur in 1990 and in 1999 also lead was included. For the current study a chemical scheme for mercury has been included and the model is now applied to the mercury transport problem. Some experiments with the formulation of the mercury chemistry during the Polar Sunrise are carried out in order to investigate the observed depletion. Some of the main conclusions of the work described in this paper are that atmospheric transport of mercury is a very important pathway into the Arctic and that mercury depletion in the Arctic troposphere during the Polar Sunrise contributes considerably to the deposition of mercury in the Arctic.