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Abstract: This dataset contains integrated hydrochemical and mercury measurements from a glacially fed river near Narsarsuaq, southern Greenland, collected to quantify how ice melt-driven hydrology controls mercury transport and speciation in an Arctic catchment. It includes daily time series of discharge, precipitation, suspended sediment concentration, and supporting geochemical analytes (including dissolved organic carbon and major and minor nutrients), alongside filtered and unfiltered total mercury, monomethylmercury, particulate mercury, and mercury stable isotope measurements. In addition to the daily time series, the file contains data from synoptic samples collected across the region for assessment of changing mercury sources; continuous hydrological records across the melt season; and atmospheric mercury measurements collected across the catchment from active mercury air samplers. Quality-control tables for mercury isotope standards (including repeated analyses of National Institute of Standards and Technology (NIST) reference materials) are included to document analytical precision and accuracy and to support reuse of the isotope data. Field blanks and blanks from geochemical data are also provided. Collectively, these data offer a detailed basis for evaluating coupled hydrological and biogeochemical controls on mercury cycling in a changing environment and for comparative analyses with other cryospheric and high-latitude river systems.
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Geochemical data from Mercury biogeochemical cycling and Export from Greenland to the Arctic (MEGA) project (Southwest Greenland, 2023)
Abstract: This dataset contains integrated hydrochemical and mercury measurements from a glacially fed river in Kangerlussuaq, Greenland, collected to quantify how ice melt-driven hydrology controls mercury transport and speciation in an Arctic catchment. It includes daily time series of discharge, precipitation, suspended sediment concentration, and supporting geochemical analytes (including dissolved organic carbon and major and minor nutrients), alongside filtered and unfiltered total mercury, monomethylmercury, particulate mercury, and sequential particulate mercury extractions. The file also provides derived variables such as instantaneous flux estimates, enabling reconstruction of concentration-discharge relationships. In addition to the daily time series, the file contains data from synoptic samples collected across the Kangerlussuaq catchment for assessment of changing mercury sources; mercury stable isotope ratios from the daily river sampling site; continuous suspended sediment and specific conductivity records across the melt season; atmospheric mercury measurements collected across the catchment from mercury air samplers; and fjord hydrography, including filtered and particulate mercury concentrations across fjord surface waters and depths. Quality-control tables for mercury isotope standards (including repeated analyses of National Institute of Standards and Technology (NIST) reference materials) are included to document analytical precision and accuracy and to support reuse of the isotope data. Field blanks and blanks from sequential particulate mercury extractions are also provided. Collectively, these data offer a detailed basis for evaluating coupled hydrological and biogeochemical controls on mercury cycling in a changing environment and for comparative analyses with other cryospheric and high-latitude river systems.
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- Award ID(s):
- 2232980
- PAR ID:
- 10704197
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Mercury Biogeochemistry Cryosphere Glacier Time series Mercury stable isotopes Fjords Southwest Greenland Kangerlussuaq
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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