Dynamic oxidation of gaseous mercury in the Arctic troposphere at polar sunrise.
Gaseous elemental mercury (Hg0) is a globally distributed air toxin with a long atmospheric residence time. Any process that reduces its atmospheric lifetime increases its potential accumulation in the biosphere. Our data from Barrow, AK, at 71 degrees N show that rapid, photochemically driven oxidation of boundary-layer Hg0 after polar sunrise, probably by reactive halogens, creates a rapidly depositing species of oxidized gaseous mercury in the remote Arctic troposphere at concentrations in excess of 900 pg m(-3). This mercury accumulates in the snowpack during polar spring at an accelerated rate in a form that is bioavailable to bacteria and is released with snowmelt during the summer emergence of the Arctic ecosystem. Evidence suggests that this is a recent phenomenon that may be occurring throughout the earth's polar regions.
Lindberg
Steve E
SE
Environmental Sciences Division, Oak Ridge National Laboratory, Tennessee 37831-6038, USA. Lindbergse@ornl.gov
Brooks
Steve
S
Lin
C J
CJ
Scott
Karen J
KJ
Landis
Matthew S
MS
Stevens
Robert K
RK
Goodsite
Mike
M
Richter
Andreas
A
D000393:Air Pollutants / Q000032:analysis*; D001110:Arctic Regions; D001419:Bacteria; D001682:Biological Availability; D017753:Ecosystem; D004784:Environmental Monitoring; D005740:Gases; D008628:Mercury / Q000032:analysis / Q000737:chemistry*; D010084:Oxidation-Reduction; D010507:Periodicity; D010777:Photochemistry; D012914:Snow
D000393:Air Pollutants; D005740:Gases; D008628:Mercury