Large mercury release from the Greenland Ice Sheet invalidated

• DOI: 10.1126/sciadv.adi7760
• Publication Date: 2024-01-26T18:58:19Z
• Authors: Christian Juncher...; Jens Søndergaard; Martin Mørk Larsen; Kristian Kjelleru...; Diogo Rosa; Sarah Elise Sapper; Lars-Eric Heimbür...; Stephen G. Kohler; Feiyue Wang; Zhiyuan Gao; Debbie Armstrong; Christian Nyrop A...
• Keywords: 0301 basic medicine; 0303 health sciences; Earth, Environmental, Ecological, and Space Sciences; [SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDU.STU.OC] Sciences of the Universe [physics]/Earth Sciences/Oceanography; [SDU.STU.GL] Sciences of the Universe [physics]/Earth Sciences/Glaciology

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.