ARL News

Mercury in the Arctic

 

March 4, 2003

Even in winter, the coastal tundra at Barrow, AK emits gaseous elemental mercury (GEM) to the atmosphere. Mercury is annually deposited to the snowpack in spring before snowmelt. Snow melt produces the strongest return to the atmosphere, but much deposited mercury remains in the meltwater to be emitted slowly through the summer. Three months of flux measurement this winter show the process continuing despite Arctic night and new snow. The nearly continuous flux averaged 0.65 ng(Hg)m-2hr-1, two orders of magnitude below the peak emission at snow melt, but significant over the long term. This average flux agreed very well with the value of 0.82 ng(Hg)m-2hr-1 found in chamber measurements on the snowpack in January 2002.