Antarctic winter mercury and ozone depletion events over sea ice
During atmospheric mercury and ozone depletion events in the springtime in polar regions gaseous elemental mercury and ozone undergo rapid declines. Mercury is quicldy transformed into oxidation products, which are subsequently removed by deposition. Here we show that such events also occur during A...
Published in: | Atmospheric Environment |
---|---|
Main Authors: | , , , , , , , , |
Language: | unknown |
Published: |
2016
|
Subjects: | |
Online Access: | https://doi.org/10.1016/j.atmosenv.2016.01.023 https://research.chalmers.se/en/publication/233394 |
id |
ftchalmersuniv:oai:research.chalmers.se:233394 |
---|---|
record_format |
openpolar |
spelling |
ftchalmersuniv:oai:research.chalmers.se:233394 2023-05-15T14:01:58+02:00 Antarctic winter mercury and ozone depletion events over sea ice Nerentorp, Michelle Gårdfeldt, Katarina Jourdain, B. Abrahamsson, Katarina Granfors, Anna Ahnoff, Martin Dommergue, A. Mejean, G. Jacobi, H. W. 2016 text https://doi.org/10.1016/j.atmosenv.2016.01.023 https://research.chalmers.se/en/publication/233394 unknown http://dx.doi.org/10.1016/j.atmosenv.2016.01.023 https://research.chalmers.se/en/publication/233394 Chemical Sciences Environmental Sciences elemental mercury ozone Antarctica surface Mercury Depletion event springtime depletion molecular halogens dissolved gaseous mercury tropospheric bro polar sunrise coastal antarctica Sea ice arctic-ocean Meteorology & Atmospheric Sciences Environmental Sciences & Ecology atmospheric mercury 2016 ftchalmersuniv https://doi.org/10.1016/j.atmosenv.2016.01.023 2022-12-11T06:52:19Z During atmospheric mercury and ozone depletion events in the springtime in polar regions gaseous elemental mercury and ozone undergo rapid declines. Mercury is quicldy transformed into oxidation products, which are subsequently removed by deposition. Here we show that such events also occur during Antarctic winter over sea ice areas, leading to additional deposition of mercury. Over four months in the Weddell Sea we measured gaseous elemental, oxidized, and particulate-bound mercury, as well as ozone in the troposphere and total and elemental mercury concentrations in snow, demonstrating a series of depletion and deposition events between July and September. The winter depletions in July were characterized by stronger correlations between mercury and ozone and larger formation of particulate-bound mercury in air compared to later spring events. It appears that light at large solar zenith angles is sufficient to initiate the photolytic formation of halogen radicals. We also propose a dark mechanism that could explain observed events in air masses coming from dark regions. Br-2 that could be the main actor in dark conditions was possibly formed in high concentrations in the marine boundary layer in the dark. These high concentrations may also have caused the formation of high concentrations of CHBr3 and CH2I2 in the top layers of the Antarctic sea ice observed during winter. These new findings show that the extent of depletion events is larger than previously believed and that winter depletions result in additional deposition of mercury that could be transferred to marine and terrestrial ecosystems. Other/Unknown Material Antarc* Antarctic Antarctica Arctic Arctic Ocean Sea ice Weddell Sea Chalmers University of Technology: Chalmers research Antarctic Arctic Arctic Ocean The Antarctic Weddell Weddell Sea Atmospheric Environment 129 125 132 |
institution |
Open Polar |
collection |
Chalmers University of Technology: Chalmers research |
op_collection_id |
ftchalmersuniv |
language |
unknown |
topic |
Chemical Sciences Environmental Sciences elemental mercury ozone Antarctica surface Mercury Depletion event springtime depletion molecular halogens dissolved gaseous mercury tropospheric bro polar sunrise coastal antarctica Sea ice arctic-ocean Meteorology & Atmospheric Sciences Environmental Sciences & Ecology atmospheric mercury |
spellingShingle |
Chemical Sciences Environmental Sciences elemental mercury ozone Antarctica surface Mercury Depletion event springtime depletion molecular halogens dissolved gaseous mercury tropospheric bro polar sunrise coastal antarctica Sea ice arctic-ocean Meteorology & Atmospheric Sciences Environmental Sciences & Ecology atmospheric mercury Nerentorp, Michelle Gårdfeldt, Katarina Jourdain, B. Abrahamsson, Katarina Granfors, Anna Ahnoff, Martin Dommergue, A. Mejean, G. Jacobi, H. W. Antarctic winter mercury and ozone depletion events over sea ice |
topic_facet |
Chemical Sciences Environmental Sciences elemental mercury ozone Antarctica surface Mercury Depletion event springtime depletion molecular halogens dissolved gaseous mercury tropospheric bro polar sunrise coastal antarctica Sea ice arctic-ocean Meteorology & Atmospheric Sciences Environmental Sciences & Ecology atmospheric mercury |
description |
During atmospheric mercury and ozone depletion events in the springtime in polar regions gaseous elemental mercury and ozone undergo rapid declines. Mercury is quicldy transformed into oxidation products, which are subsequently removed by deposition. Here we show that such events also occur during Antarctic winter over sea ice areas, leading to additional deposition of mercury. Over four months in the Weddell Sea we measured gaseous elemental, oxidized, and particulate-bound mercury, as well as ozone in the troposphere and total and elemental mercury concentrations in snow, demonstrating a series of depletion and deposition events between July and September. The winter depletions in July were characterized by stronger correlations between mercury and ozone and larger formation of particulate-bound mercury in air compared to later spring events. It appears that light at large solar zenith angles is sufficient to initiate the photolytic formation of halogen radicals. We also propose a dark mechanism that could explain observed events in air masses coming from dark regions. Br-2 that could be the main actor in dark conditions was possibly formed in high concentrations in the marine boundary layer in the dark. These high concentrations may also have caused the formation of high concentrations of CHBr3 and CH2I2 in the top layers of the Antarctic sea ice observed during winter. These new findings show that the extent of depletion events is larger than previously believed and that winter depletions result in additional deposition of mercury that could be transferred to marine and terrestrial ecosystems. |
author |
Nerentorp, Michelle Gårdfeldt, Katarina Jourdain, B. Abrahamsson, Katarina Granfors, Anna Ahnoff, Martin Dommergue, A. Mejean, G. Jacobi, H. W. |
author_facet |
Nerentorp, Michelle Gårdfeldt, Katarina Jourdain, B. Abrahamsson, Katarina Granfors, Anna Ahnoff, Martin Dommergue, A. Mejean, G. Jacobi, H. W. |
author_sort |
Nerentorp, Michelle |
title |
Antarctic winter mercury and ozone depletion events over sea ice |
title_short |
Antarctic winter mercury and ozone depletion events over sea ice |
title_full |
Antarctic winter mercury and ozone depletion events over sea ice |
title_fullStr |
Antarctic winter mercury and ozone depletion events over sea ice |
title_full_unstemmed |
Antarctic winter mercury and ozone depletion events over sea ice |
title_sort |
antarctic winter mercury and ozone depletion events over sea ice |
publishDate |
2016 |
url |
https://doi.org/10.1016/j.atmosenv.2016.01.023 https://research.chalmers.se/en/publication/233394 |
geographic |
Antarctic Arctic Arctic Ocean The Antarctic Weddell Weddell Sea |
geographic_facet |
Antarctic Arctic Arctic Ocean The Antarctic Weddell Weddell Sea |
genre |
Antarc* Antarctic Antarctica Arctic Arctic Ocean Sea ice Weddell Sea |
genre_facet |
Antarc* Antarctic Antarctica Arctic Arctic Ocean Sea ice Weddell Sea |
op_relation |
http://dx.doi.org/10.1016/j.atmosenv.2016.01.023 https://research.chalmers.se/en/publication/233394 |
op_doi |
https://doi.org/10.1016/j.atmosenv.2016.01.023 |
container_title |
Atmospheric Environment |
container_volume |
129 |
container_start_page |
125 |
op_container_end_page |
132 |
_version_ |
1766272036084121600 |