Understanding the sources and transformations of mercury (Hg) in the free troposphere is a critical aspect of global Hg research. Here we present one year of observations of atmospheric Hg speciation and gaseous elemental Hg (GEM) isotopic composition at the high-altitude Pic du Midi Observatory (2860 m above sea level) in France. Biweekly integrated GEM from February 2012 to January 2013 revealed significant variations in delta Hg-202(GEM) (-0.04 parts per thousand to 0.52 parts per thousand) but not in Delta Hg-199(GEM) (-0.17 parts per thousand to -0.27 parts per thousand) or Delta Hg-200(GEM) (-0.10 parts per thousand to 0.05 parts per thousand). delta Hg-202(GEM) was negatively correlated with CO and reflected air mass origins from Europe (high CO, low delta Hg-202(GEM)) and from the Atlantic Ocean (low CO, high delta Hg-202(GEM)). We suggest that the delta Hg-202(GEM) variations represent mixing of recent low delta Hg-202(GEM) European anthropogenic emissions with high delta Hg-202(GEM) northern hemispheric background GEM. In addition, Atlantic Ocean free troposphere air masses showed a positive correlation between delta Hg-202(GEM) and gaseous oxidized Hg (GOM) concentrations, indicative of mass-dependent Hg isotope fractionation during GEM oxidation. On the basis of atmospheric delta Hg-202(GEM) and speciated Hg observations, we suggest that the oceanic free troposphere is a reservoir within which GEM is readily oxidized to GOM.
Jeroen E. Sonke,François Gheusi,Xun Wang,et al. Isotopic Composition of Gaseous Elemental Mercury in the Free Troposphere of the Pic du Midi Observatory, France[J]. Environmental Science & Technology,2016,50(11):5641-5650.
APA
Jeroen E. Sonke,François Gheusi,Xun Wang,Nicolas Marusczak,&Xuewu Fu.(2016).Isotopic Composition of Gaseous Elemental Mercury in the Free Troposphere of the Pic du Midi Observatory, France.Environmental Science & Technology,50(11),5641-5650.
MLA
Jeroen E. Sonke,et al."Isotopic Composition of Gaseous Elemental Mercury in the Free Troposphere of the Pic du Midi Observatory, France".Environmental Science & Technology 50.11(2016):5641-5650.
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