Large mercury release from the Greenland Ice Sheet invalidated

• Published in: Science Advances
• Main Authors: Jørgensen, Christian Juncher, Søndergaard, Jens, Larsen, Martin Mørk, Kjeldsen, Kristian Kjellerup, Rosa, Diogo, Sapper, Sarah Elise, Heimbürger-Boavida, Lars-Eric, Kohler, Stephen G., Wang, Feiyue, Gao, Zhiyuan, Armstrong, Debbie, Albers, Christian Nyrop
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Association for the Advancement of Science (AAAS) 2024
• Subjects: Arctic; Greenland; Ice Sheet
• Online Access: http://dx.doi.org/10.1126/sciadv.adi7760; https://www.science.org/doi/pdf/10.1126/sciadv.adi7760

The major input of mercury (Hg) to the Arctic is normally ascribed to long-range transport of anthropogenic Hg emissions. Recently, alarming concentrations of Hg in meltwater from the Greenland Ice Sheet (GrIS) were reported with bedrock as the proposed source. Reported Hg concentrations were 100 to 1000 times higher than in known freshwater systems of Greenland, calling for independent validation of the extraordinary concentrations and conclusions. Here, we present measurements of Hg at 21 glacial outlets in West Greenland showing that extreme Hg concentrations cannot be reproduced. In contrast, we find that meltwater from below the GrIS is very low in Hg, has minor implications for the global Hg budget, and pose only a very limited risk for local communities and the natural environment of Greenland.