[SunkenCiv]

In the 1 March issue of Environmental Science & Technology, the team concludes that most of the methylmercury in Arctic ice comes from water vapor that’s evaporating from the ocean through openings in the sea ice, not from precipitation. They know this, geologist and co-author Joel Blum of the University of Michigan, Ann Arbor, said in an e-mail, because they also condensed out mercury from vapors collected from open ocean waters. As far as the ultimate sources of the mercury, Blum says they remain unknown.

Thanks nd. I think the mercury comes from thermometers of the Franklin expedition. /rimshot