| Titre | Climate change and mercury in the Arctic: Abiotic interactions |
| |
| Auteur | Chételat, J; McKinney, M A; Amyot, M; Dastoor, A; Douglas, T A; Heimbürger-Boavida, L -E; Kirk, J; Kahilainen, K K; Outridge, P M ; Pelletier, N; Skov, H; St. Pierre, K; Vuorenmaa, J; Wang, F |
| Source | Science of the Total Environment vol. 824, 153715, 2022 p. 1-17, https://doi.org/10.1016/j.scitotenv.2022.153715  Accès ouvert |
| Image |  |
| Année | 2022 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20210697 |
| Éditeur | Elsevier |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1016/j.scitotenv.2022.153715 |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Sujets | mercure; géochimie du mercure; climat; pergélisol; Changement climatique |
| Illustrations | photographies; diagrammes |
| Programme | Géosciences environnementales Gestion du programme |
| Diffusé | 2022 02 09 |
| Résumé | (disponible en anglais seulement)
Dramatic environmental shifts are occuring throughout the Arctic from climate change, with consequences for the cycling of mercury (Hg). This review summarizes
the latest science on how climate change is influencing Hg transport and biogeochemical cycling in Arctic terrestrial, freshwater and marine ecosystems. As environmental changes in the Arctic continue to accelerate, a clearer picture is emerging of
the profound shifts in the climate and cryosphere, and their connections to Hg cycling. Modeling results suggest climate influences seasonal and interannual variability of atmospheric Hg deposition. The clearest evidence of current climate change
effects is for Hg transport from terrestrial catchments, where widespread permafrost thaw, glacier melt and coastal erosion are increasing the export of Hg to downstreamenvironments. Recent estimates suggest Arctic permafrost is a large global
reservoir of Hg, which is vulnerable to degradation with climate warming, although the fate of permafrost soil Hg is unclear. The increasing development of thermokarst features, the formation and expansion of thaw lakes, and increased soil erosion in
terrestrial landscapes are increasing river transport of particulate-bound Hg and altering conditions for aquatic Hg transformations. Greater organic matter transport may also be influencing the downstream transport and fate of Hg. More severe and
frequent wildfires within the Arctic and across boreal regions may be contributing to the atmospheric pool of Hg. Climate change influences on Hg biogeochemical cycling remain poorly understood. Seasonal evasion and retention of inorganic Hg may be
altered by reduced sea-ice cover and higher chloride content in snow. Experimental evidence indicates warmer temperatures enhance methylmercury production in ocean and lake sediments as well as in tundra soils. Improved geographic coverage of
measurements andmodeling approaches are needed to better evaluate net effects of climate change and long-term implications for Hg contamination in the Arctic. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Les preuves actuelles indiquent que les changements climatiques influencent considérablement certains aspects du cycle du mercure dans
l'Arctique. Le pergélisol arctique contient un réservoir de mercure d'importance mondiale, vulnérable à la dégradation et au rejet dans les cours d'eau. Le dégel du pergélisol, la fonte des glaciers et l'érosion côtière augmentent l'exportation de
mercure dans les lacs, les rivières et finalement l'océan Arctique. Des incendies de forêt plus graves et plus fréquents dans l'Arctique et dans les régions boréales pourraient contribuer à la concentration atmosphérique de mercure. Des expériences
montrent que des températures plus chaudes augmentent la production de méthylmercure dans les sédiments et les sols de l'Arctique, ce qui suggère la possibilité de concentrations de mercure plus élevées dans les poissons et la faune. Cependant, les
effets nets globaux du changement climatique sur la contamination par le mercure dans l'Arctique restent mal connus. |
| GEOSCAN ID | 329696 |
|
|