Mercury mobilization and export from the Greenland Ice Sheet using an ice-to-ocean approach
Abstract The Greenland Ice Sheet (GrIS) is a poorly constrained source of mercury (Hg) to Arctic ecosystems. We measured Hg concentrations and stable isotopes along an ice-to-ocean continuum to identify controls on GrIS Hg export. Early-season permafrost melt and rainfall produced high filtered total mercury (fTHg, ~17 pM) and monomethylmercury (MMHg, ~2 pM). As subglacial drainage evolved, particulate Hg doubled (from ~8 to 17 pM) and MMHg production remained elevated, indicating Hg mobilization from subglacial environments. Shifts in Hg stable isotope ratios and $$\Delta$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Δ</mml:mi> </mml:math> 199 Hg mass balance show supraglacial sources contribute 20–48% of exported Hg, suggesting subglacial inputs dominate the seasonal Hg flux. Fjord waters were enriched in fTHg ( ~ 10 pM) and MMHg ( ~ 2 pM) relative to rivers, consistent with particulate Hg transformations and terrestrial Hg inputs. The estimated GrIS Hg yield ( ~ 23 mmol km −2 yr −1 ) is similar to that of Arctic rivers and will likely increase with climate-driven mass loss.
Authors
- Ian Delaney (ORCID: https://orcid.org/0000-0003-1722-0600)
- Guillaume Lamarche‐Gagnon (ORCID: https://orcid.org/0000-0002-3444-7834)
- Sarah E. Janssen (ORCID: https://orcid.org/0000-0003-4432-3154)
- Michael T. Tate (ORCID: https://orcid.org/0000-0003-1525-1219)
- Marek Stibal (ORCID: https://orcid.org/0000-0002-9998-5086)
- Johannes West (ORCID: https://orcid.org/0000-0002-2856-7549)
- Amina T. Schartup (ORCID: https://orcid.org/0000-0002-9289-8107)
- Brett A. Poulin (ORCID: https://orcid.org/0000-0002-5555-7733)
- Jon Hawkings (ORCID: https://orcid.org/0000-0003-4813-8474)
- Jack G. Murphy (ORCID: https://orcid.org/0000-0002-7579-6213)
- Marjolein Gevers (ORCID: https://orcid.org/0000-0002-5866-7436)
- Eva L. Doting (ORCID: https://orcid.org/0000-0002-2195-8299)
- Iris Kübler-Dudgeon
- Jade Hatton (ORCID: https://orcid.org/0000-0002-9408-7981)
- David McCabe
- Amina Youssef (ORCID: https://orcid.org/0009-0000-5229-407X)
- Abe Doroshow
- Emma K. Ferrer (ORCID: https://orcid.org/0009-0007-5320-3409)
- Marissa Despins
- Carl Lamborg
- Leah M. Hopf
Institutions
- United States Geological Survey (US)
- Scripps Institution of Oceanography (US)
- University of California, Santa Cruz (US)
- Charles University (CZ)
- UK Centre for Ecology & Hydrology (GB)
- Centre for Arctic Gas Hydrate, Environment and Climate (NO)
- Norwegian Institute for Nature Research (NO)
- UiT The Arctic University of Norway (NO)
- University of Pennsylvania (US)
- University of California, Davis (US)
- University of Lausanne (CH)
Publication Details
- Journal
- Communications Earth & Environment
- Published
- 2026-07-16
- DOI
- https://doi.org/10.1038/s43247-026-03818-z
- Primary Topic
- Mercury impact and mitigation studies
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- University of Pennsylvania
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Norges Forskningsråd
- U.S. Geological Survey