Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222
We discuss remote terrestrial influences on boundary layer air over the Southern Ocean and Antarctica, and the mechanisms by which they arise, using atmospheric radon observations as a proxy. Our primary motivation was to enhance the scientific community's ability to understand and quantify the...
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ftunivwollongong:oai:ro.uow.edu.au:smhpapers1-1498 2023-05-15T13:57:48+02:00 Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 Chambers, Scott Preunkert, Susanne Weller, Rolf Hong, Sang-Bum Humphries, Ruhi S Tositti, Laura Angot, Helene Legrand, Michel Williams, Alastair G Griffiths, Alan Crawford, Jagoda Simmons, Jack B Choi, Taejin Krummel, Paul B Molloy, Suzie B Loh, Zoe Galbally, Ian E Wilson, Stephen R Magand, Olivier Sprovieri, Francesca Pirrone, Nicola Dommergue, Aurelien 2018-01-01T08:00:00Z application/pdf https://ro.uow.edu.au/smhpapers1/486 https://ro.uow.edu.au/cgi/viewcontent.cgi?article=1498&context=smhpapers1 unknown Research Online https://ro.uow.edu.au/smhpapers1/486 https://ro.uow.edu.au/cgi/viewcontent.cgi?article=1498&context=smhpapers1 Faculty of Science, Medicine and Health - Papers: Part B article 2018 ftunivwollongong 2021-08-23T22:25:11Z We discuss remote terrestrial influences on boundary layer air over the Southern Ocean and Antarctica, and the mechanisms by which they arise, using atmospheric radon observations as a proxy. Our primary motivation was to enhance the scientific community's ability to understand and quantify the potential effects of pollution, nutrient or pollen transport from distant land masses to these remote, sparsely instrumented regions. Seasonal radon characteristics are discussed at 6 stations (Macquarie Island, King Sejong, Neumayer, Dumont d'Urville, Jang Bogo and Dome Concordia) using 1-4 years of continuous observations. Context is provided for differences observed between these sites by Southern Ocean radon transects between 45 and 67◦S made by the Research Vessel Investigator. Synoptic transport of continental air within the marine boundary layer (MBL) dominated radon seasonal cycles in the mid-Southern Ocean site (Macquarie Island). MBL synoptic transport, tropospheric injection, and Antarctic outflow all contributed to the seasonal cycle at the sub-Antarctic site (King Sejong). Tropospheric subsidence and injection events delivered terrestrially influenced air to the Southern Ocean MBL in the vicinity of the circumpolar trough (or "Polar Front"). Katabatic outflow events from Antarctica were observed to modify trace gas and aerosol characteristics of the MBL 100-200 km off the coast. Radon seasonal cycles at coastal Antarctic sites were dominated by a combination of local radon sources in summer and subsidence of terrestrially influenced tropospheric air, whereas those on the Antarctic Plateau were primarily controlled by tropospheric subsidence. Separate characterization of long-term marine and katabatic flow air masses at Dumont d'Urville revealed monthly mean differences in summer of up to 5 ppbv in ozone and 0.3 ng m−3 in gaseous elemental mercury. These differences were largely attributed to chemical processes on the Antarctic Plateau. A comparison of our observations with some Antarctic radon simulations by global climate models over the past two decades indicated that: (i) some models overestimate synoptic transport to Antarctica in the MBL, (ii) the seasonality of the Antarctic ice sheet needs to be better represented in models, (iii) coastal Antarctic radon sources need to be taken into account, and (iv) the underestimation of radon in subsiding tropospheric air needs to be investigated. Article in Journal/Newspaper Antarc* Antarctic Antarctica Ice Sheet Macquarie Island Southern Ocean University of Wollongong, Australia: Research Online Antarctic Bogo ENVELOPE(9.783,9.783,63.095,63.095) Dumont d'Urville ENVELOPE(140.017,140.017,-66.667,-66.667) Dumont-d'Urville ENVELOPE(140.013,140.013,-66.667,-66.667) Neumayer Southern Ocean The Antarctic |
institution |
Open Polar |
collection |
University of Wollongong, Australia: Research Online |
op_collection_id |
ftunivwollongong |
language |
unknown |
description |
We discuss remote terrestrial influences on boundary layer air over the Southern Ocean and Antarctica, and the mechanisms by which they arise, using atmospheric radon observations as a proxy. Our primary motivation was to enhance the scientific community's ability to understand and quantify the potential effects of pollution, nutrient or pollen transport from distant land masses to these remote, sparsely instrumented regions. Seasonal radon characteristics are discussed at 6 stations (Macquarie Island, King Sejong, Neumayer, Dumont d'Urville, Jang Bogo and Dome Concordia) using 1-4 years of continuous observations. Context is provided for differences observed between these sites by Southern Ocean radon transects between 45 and 67◦S made by the Research Vessel Investigator. Synoptic transport of continental air within the marine boundary layer (MBL) dominated radon seasonal cycles in the mid-Southern Ocean site (Macquarie Island). MBL synoptic transport, tropospheric injection, and Antarctic outflow all contributed to the seasonal cycle at the sub-Antarctic site (King Sejong). Tropospheric subsidence and injection events delivered terrestrially influenced air to the Southern Ocean MBL in the vicinity of the circumpolar trough (or "Polar Front"). Katabatic outflow events from Antarctica were observed to modify trace gas and aerosol characteristics of the MBL 100-200 km off the coast. Radon seasonal cycles at coastal Antarctic sites were dominated by a combination of local radon sources in summer and subsidence of terrestrially influenced tropospheric air, whereas those on the Antarctic Plateau were primarily controlled by tropospheric subsidence. Separate characterization of long-term marine and katabatic flow air masses at Dumont d'Urville revealed monthly mean differences in summer of up to 5 ppbv in ozone and 0.3 ng m−3 in gaseous elemental mercury. These differences were largely attributed to chemical processes on the Antarctic Plateau. A comparison of our observations with some Antarctic radon simulations by global climate models over the past two decades indicated that: (i) some models overestimate synoptic transport to Antarctica in the MBL, (ii) the seasonality of the Antarctic ice sheet needs to be better represented in models, (iii) coastal Antarctic radon sources need to be taken into account, and (iv) the underestimation of radon in subsiding tropospheric air needs to be investigated. |
format |
Article in Journal/Newspaper |
author |
Chambers, Scott Preunkert, Susanne Weller, Rolf Hong, Sang-Bum Humphries, Ruhi S Tositti, Laura Angot, Helene Legrand, Michel Williams, Alastair G Griffiths, Alan Crawford, Jagoda Simmons, Jack B Choi, Taejin Krummel, Paul B Molloy, Suzie B Loh, Zoe Galbally, Ian E Wilson, Stephen R Magand, Olivier Sprovieri, Francesca Pirrone, Nicola Dommergue, Aurelien |
spellingShingle |
Chambers, Scott Preunkert, Susanne Weller, Rolf Hong, Sang-Bum Humphries, Ruhi S Tositti, Laura Angot, Helene Legrand, Michel Williams, Alastair G Griffiths, Alan Crawford, Jagoda Simmons, Jack B Choi, Taejin Krummel, Paul B Molloy, Suzie B Loh, Zoe Galbally, Ian E Wilson, Stephen R Magand, Olivier Sprovieri, Francesca Pirrone, Nicola Dommergue, Aurelien Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 |
author_facet |
Chambers, Scott Preunkert, Susanne Weller, Rolf Hong, Sang-Bum Humphries, Ruhi S Tositti, Laura Angot, Helene Legrand, Michel Williams, Alastair G Griffiths, Alan Crawford, Jagoda Simmons, Jack B Choi, Taejin Krummel, Paul B Molloy, Suzie B Loh, Zoe Galbally, Ian E Wilson, Stephen R Magand, Olivier Sprovieri, Francesca Pirrone, Nicola Dommergue, Aurelien |
author_sort |
Chambers, Scott |
title |
Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 |
title_short |
Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 |
title_full |
Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 |
title_fullStr |
Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 |
title_full_unstemmed |
Characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 |
title_sort |
characterizing atmospheric transport pathways to antarctica and the remote southern ocean using radon-222 |
publisher |
Research Online |
publishDate |
2018 |
url |
https://ro.uow.edu.au/smhpapers1/486 https://ro.uow.edu.au/cgi/viewcontent.cgi?article=1498&context=smhpapers1 |
long_lat |
ENVELOPE(9.783,9.783,63.095,63.095) ENVELOPE(140.017,140.017,-66.667,-66.667) ENVELOPE(140.013,140.013,-66.667,-66.667) |
geographic |
Antarctic Bogo Dumont d'Urville Dumont-d'Urville Neumayer Southern Ocean The Antarctic |
geographic_facet |
Antarctic Bogo Dumont d'Urville Dumont-d'Urville Neumayer Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Antarctica Ice Sheet Macquarie Island Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Macquarie Island Southern Ocean |
op_source |
Faculty of Science, Medicine and Health - Papers: Part B |
op_relation |
https://ro.uow.edu.au/smhpapers1/486 https://ro.uow.edu.au/cgi/viewcontent.cgi?article=1498&context=smhpapers1 |
_version_ |
1766265690460782592 |