Mercury content and isotopic composition of frost flower, surface snow and brine samples near Barrow, Alaska

Fuente: PANGAEA
Salvato in:
Dettagli Bibliografici
Autori principali: Sherman, Laura S, Blum, Joel D, Douglas, Thomas A, Steffen, Alexandra
Natura: Dataset Open Access
Lingua:en
Pubblicazione: PANGAEA 2012
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1867168562923175936
author Sherman, Laura S
Blum, Joel D
Douglas, Thomas A
Steffen, Alexandra
author_facet Sherman, Laura S
Blum, Joel D
Douglas, Thomas A
Steffen, Alexandra
collection Datos científicos de ciencias marinas y ambientales
contents Frost flowers are ice crystals that grow on refreezing sea ice leads in Polar Regions by wicking brine from the sea ice surface and accumulating vapor phase condensate. These crystals contain high concentrations of mercury (Hg) and are believed to be a source of reactive halogens, but their role in Hg cycling and impact on the fate of Hg deposited during atmospheric mercury depletion events (AMDEs) are not well understood. We collected frost flowers growing on refreezing sea ice near Barrow, Alaska (U.S.A.) during an AMDE in March 2009 and measured Hg concentrations and Hg stable isotope ratios in these samples to determine the origin of Hg associated with the crystals. We observed decreasing Delta199Hg values in the crystals as they grew from new wet frost flowers (mean Delta199Hg = 0.77 ± 0.13 per mil, 1 s.d.) to older dry frost flowers (mean Delta199Hg = 0.10 ± 0.05 per mil, 1 s.d.). Over the same time period, mean Hg concentrations in these samples increased from 131 ± 6 ng/L (1 s.d.) to 180 ± 28 ng/L (1 s.d.). Coupled with a previous study of Hg isotopic fractionation during AMDEs, these results suggest that Hg initially deposited to the local snowpack was subsequently reemitted during photochemical reduction reactions and ultimately accumulated on the frost flowers. As a result of this process, frost flowers may lead to enhanced local retention of Hg deposited during AMDEs and may increase Hg loading to the Arctic Ocean.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_809260
institution PANGAEA
language en
publishDate 2012
publisher PANGAEA
record_format pangaea
spellingShingle Mercury content and isotopic composition of frost flower, surface snow and brine samples near Barrow, Alaska
Sherman, Laura S
Blum, Joel D
Douglas, Thomas A
Steffen, Alexandra
Barrow, Alaska, USA; Barrow2009_OASIS; International Polar Year (2007-2008); IPY; SNOW; Snow/ice sample
Frost flowers are ice crystals that grow on refreezing sea ice leads in Polar Regions by wicking brine from the sea ice surface and accumulating vapor phase condensate. These crystals contain high concentrations of mercury (Hg) and are believed to be a source of reactive halogens, but their role in Hg cycling and impact on the fate of Hg deposited during atmospheric mercury depletion events (AMDEs) are not well understood. We collected frost flowers growing on refreezing sea ice near Barrow, Alaska (U.S.A.) during an AMDE in March 2009 and measured Hg concentrations and Hg stable isotope ratios in these samples to determine the origin of Hg associated with the crystals. We observed decreasing Delta199Hg values in the crystals as they grew from new wet frost flowers (mean Delta199Hg = 0.77 ± 0.13 per mil, 1 s.d.) to older dry frost flowers (mean Delta199Hg = 0.10 ± 0.05 per mil, 1 s.d.). Over the same time period, mean Hg concentrations in these samples increased from 131 ± 6 ng/L (1 s.d.) to 180 ± 28 ng/L (1 s.d.). Coupled with a previous study of Hg isotopic fractionation during AMDEs, these results suggest that Hg initially deposited to the local snowpack was subsequently reemitted during photochemical reduction reactions and ultimately accumulated on the frost flowers. As a result of this process, frost flowers may lead to enhanced local retention of Hg deposited during AMDEs and may increase Hg loading to the Arctic Ocean.
title Mercury content and isotopic composition of frost flower, surface snow and brine samples near Barrow, Alaska
topic Barrow, Alaska, USA; Barrow2009_OASIS; International Polar Year (2007-2008); IPY; SNOW; Snow/ice sample
url https://doi.org/10.1594/PANGAEA.809260