| Title | Mercury in the Canadian Arctic terrestrial environment: an update |
| Author | Gamberg, M; Chételat, J; Poulain, A J; Zdanowicz, C; Zheng, J |
| Source | Science of the Total Environment vol. 509-510, 2015 p. 28-40, https://doi.org/10.1016/j.scitotenv.2014.04.070 (Open Access) |
| Year | 2015 |
| Alt Series | Earth Sciences Sector, Contribution Series 20140130 |
| Publisher | Elsevier BV |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Nunavut; Northwest Territories |
| NTS | 15; 16; 25; 26; 27; 36; 37; 38; 39; 120; 340; 560; 46; 47; 48; 49; 56; 57; 58; 59; 66; 67; 68; 69; 76; 77; 78; 79; 86; 87; 88; 89; 97; 98; 99 |
| Area | Canadian Arctic; Ellesmere Island; Devon Island; Baffin Island |
| Lat/Long WENS | -128.0000 -56.0000 85.0000 61.0000 |
| Subjects | environmental geology; mercury; mercury geochemistry; pollutants; heavy metals contamination; snow; glaciers; vegetation |
| Illustrations | drawings; plots; graphs; tables; location maps |
| Program | environmental impacts and adaptation in the northern environment, Environmental Geoscience |
| Abstract | Contaminants in the Canadian Arctic have been studied over the last twenty years under the guidance of the Northern Contaminants Program. This paper provides the current state of knowledge on mercury
(Hg) in the Canadian Arctic terrestrial environment. Snow, ice, and soils on land are key reservoirs for atmospheric deposition and, in turn, can become sources of mercury (Hg) through the melting of terrestrial ice and snow and via soil erosion. In
the Canadian Arctic, new data have been collected for snow and ice that provide more information on the flux of Hg to the cryosphere and its post-depositional fate. Terrestrial snow total Hg (THg) concentrations are highly variable but on average,
relatively low, while methylmercury (MeHg) levels in Arctic snow are lower still. Hg in snow may be affected by proximity to marine aerosols (and halogens), burial and redistribution within the snow pack. On average, THg concentrations on Arctic
glaciers of eastern Canada are much lower than those reported in Arctic snow. Regional accumulation rates of THg in glacier snow varied little during the past century but show evidence of an increasing north-to-south gradient. Temporal trends of THg
in glacier cores indicate an abrupt increase in the early 1990s followed by more stable levels. Reasons for the sustained higher THg concentrations are unclear. Although Arctic soils typically had low THg concentrations, the flux of Hg from coastal
erosion of permafrost soils is a significant source to the Arctic Ocean. Terrestrial Arctic wildlife typically have low levels of Hg, caribou (Rangifer tarandus) usually having the highest because they consume large amounts of lichen. Frequent
monitoring of the Yukon's Porcupine caribou herd indicates that THg concentrations vary among years but there has been no significant increase or decrease over the last two decades. |
| Summary | (Plain Language Summary, not published)
Contaminants in the Canadian Arctic have been studied over the last twenty years. This paper provides the current state of knowledge on mercury (Hg) in
the Canadian Arctic terrestrial environment. This update summarized the significant advances were achieved in understanding of dynamics of Hg in terrestrial environments of the Canadian Arctic. Total mercury (THg) and methyl mercury (MeHg) are found
at generally low levels within Arctic terrestrial environments, with the exception of lowland coastal areas where high snow THg concentrations may result from atmospheric mercury depletion events (AMDEs). Water-logged Arctic soils have the potential
to methylate mercury and the coastal erosion of permafrost is a significant source of Hg to the Arctic Ocean. Frequent monitoring of the Yukon¿s Porcupine caribou herd indicates that THg concentrations vary among years but there has been no
significant increase or decrease over the last two decades. |
| GEOSCAN ID | 294849 |
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