Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa
Mercury (Hg) contamination is ubiquitous. In order to assess its emissions, transport, atmospheric reactivity, and deposition pathways, worldwide Hg monitoring has been implemented over the past 10–20 years, albeit with only a few stations in the Southern Hemisphere. Consequently, little is known ab...
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ftcopernicus:oai:publications.copernicus.org:acp83144 2023-05-15T13:31:39+02:00 Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa Bieser, Johannes Angot, Hélène Slemr, Franz Martin, Lynwill 2020-09-08 application/pdf https://doi.org/10.5194/acp-20-10427-2020 https://acp.copernicus.org/articles/20/10427/2020/ eng eng doi:10.5194/acp-20-10427-2020 https://acp.copernicus.org/articles/20/10427/2020/ eISSN: 1680-7324 Text 2020 ftcopernicus https://doi.org/10.5194/acp-20-10427-2020 2020-09-14T16:22:14Z Mercury (Hg) contamination is ubiquitous. In order to assess its emissions, transport, atmospheric reactivity, and deposition pathways, worldwide Hg monitoring has been implemented over the past 10–20 years, albeit with only a few stations in the Southern Hemisphere. Consequently, little is known about the relative contribution of marine and terrestrial Hg sources, which is important in the context of growing interest in effectiveness evaluation of Hg mitigation policies. This paper constitutes Part 2 of the study describing a decade of atmospheric Hg concentrations at Cape Point, South Africa, i.e. the first long-term ( > 10 years) observations in the Southern Hemisphere. Building on the trend analysis reported in Part 1, here we combine atmospheric Hg data with a trajectory model to investigate sources and sinks of Hg at Cape Point. We find that the continent is the major sink, and the ocean, especially its warm regions (i.e. the Agulhas Current), is the major source for Hg. Further, we find that mercury concentrations and trends from long-range transport are independent of the source region (e.g. South America, Antarctica) and thus indistinguishable. Therefore, by filtering out air masses from source and sink regions we are able to create a dataset representing a southern hemispheric background Hg concentrations. Based on this dataset, we were able to show that the interannual variability in Hg concentrations at Cape Point is not driven by changes in atmospheric circulation but rather due to changes in global emissions (gold mining and biomass burning). Text Antarc* Antarctica Copernicus Publications: E-Journals Atmospheric Chemistry and Physics 20 17 10427 10439 |
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Copernicus Publications: E-Journals |
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English |
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Mercury (Hg) contamination is ubiquitous. In order to assess its emissions, transport, atmospheric reactivity, and deposition pathways, worldwide Hg monitoring has been implemented over the past 10–20 years, albeit with only a few stations in the Southern Hemisphere. Consequently, little is known about the relative contribution of marine and terrestrial Hg sources, which is important in the context of growing interest in effectiveness evaluation of Hg mitigation policies. This paper constitutes Part 2 of the study describing a decade of atmospheric Hg concentrations at Cape Point, South Africa, i.e. the first long-term ( > 10 years) observations in the Southern Hemisphere. Building on the trend analysis reported in Part 1, here we combine atmospheric Hg data with a trajectory model to investigate sources and sinks of Hg at Cape Point. We find that the continent is the major sink, and the ocean, especially its warm regions (i.e. the Agulhas Current), is the major source for Hg. Further, we find that mercury concentrations and trends from long-range transport are independent of the source region (e.g. South America, Antarctica) and thus indistinguishable. Therefore, by filtering out air masses from source and sink regions we are able to create a dataset representing a southern hemispheric background Hg concentrations. Based on this dataset, we were able to show that the interannual variability in Hg concentrations at Cape Point is not driven by changes in atmospheric circulation but rather due to changes in global emissions (gold mining and biomass burning). |
format |
Text |
author |
Bieser, Johannes Angot, Hélène Slemr, Franz Martin, Lynwill |
spellingShingle |
Bieser, Johannes Angot, Hélène Slemr, Franz Martin, Lynwill Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa |
author_facet |
Bieser, Johannes Angot, Hélène Slemr, Franz Martin, Lynwill |
author_sort |
Bieser, Johannes |
title |
Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa |
title_short |
Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa |
title_full |
Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa |
title_fullStr |
Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa |
title_full_unstemmed |
Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa |
title_sort |
atmospheric mercury in the southern hemisphere – part 2: source apportionment analysis at cape point station, south africa |
publishDate |
2020 |
url |
https://doi.org/10.5194/acp-20-10427-2020 https://acp.copernicus.org/articles/20/10427/2020/ |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
eISSN: 1680-7324 |
op_relation |
doi:10.5194/acp-20-10427-2020 https://acp.copernicus.org/articles/20/10427/2020/ |
op_doi |
https://doi.org/10.5194/acp-20-10427-2020 |
container_title |
Atmospheric Chemistry and Physics |
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20 |
container_issue |
17 |
container_start_page |
10427 |
op_container_end_page |
10439 |
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1766019700520648704 |