Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS
Heterogeneous photochemistry converts bromide (Br−) to reactive bromine species (Br atoms and bromine monoxide, BrO) that dominate Arctic springtime chemistry. This phenomenon has many impacts such as boundary-layer ozone depletion, mercury oxidation and deposition, and modification of the fate of h...
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ftpubman:oai:pure.mpg.de:item_2473435 2023-08-20T04:05:00+02:00 Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS Simpson, W. Peterson, P. Friess, U. Sihler, H. Lampel, J. Platt, U. Moore, C. Pratt, K. Shepson, P. Halfacre, J. Nghiem, S. 2017 http://hdl.handle.net/11858/00-001M-0000-002D-D393-C eng eng info:eu-repo/semantics/altIdentifier/doi/10.5194/acp-17-9291-2017 http://hdl.handle.net/11858/00-001M-0000-002D-D393-C Atmospheric Chemistry and Physics info:eu-repo/semantics/article 2017 ftpubman https://doi.org/10.5194/acp-17-9291-2017 2023-08-01T23:01:32Z Heterogeneous photochemistry converts bromide (Br−) to reactive bromine species (Br atoms and bromine monoxide, BrO) that dominate Arctic springtime chemistry. This phenomenon has many impacts such as boundary-layer ozone depletion, mercury oxidation and deposition, and modification of the fate of hydrocarbon species. To study environmental controls on reactive bromine events, the BRomine, Ozone, and Mercury EXperiment (BROMEX) was carried out from early March to mid-April 2012 near Barrow (Utqiaġvik), Alaska. We measured horizontal and vertical gradients in BrO with multiple-axis differential optical absorption spectroscopy (MAX-DOAS) instrumentation at three sites, two mobile and one fixed. During the campaign, a large crack in the sea ice (an open lead) formed pushing one instrument package ∼ 250 km downwind from Barrow (Utqiaġvik). Convection associated with the open lead converted the BrO vertical structure from a surface-based event to a lofted event downwind of the lead influence. The column abundance of BrO downwind of the re-freezing lead was comparable to upwind amounts, indicating direct reactions on frost flowers or open seawater was not a major reactive bromine source. When these three sites were separated by ∼ 30 km length scales of unbroken sea ice, the BrO amount and vertical distributions were highly correlated for most of the time, indicating the horizontal length scales of BrO events were typically larger than ∼ 30 km in the absence of sea ice features. Although BrO amount and vertical distribution were similar between sites most of the time, rapid changes in BrO with edges significantly smaller than this ∼ 30 km length scale episodically transported between the sites, indicating BrO events were large but with sharp edge contrasts. BrO was often found in shallow layers that recycled reactive bromine via heterogeneous reactions on snowpack. Episodically, these surface-based events propagated aloft when aerosol extinction was higher (> 0.1 km−1); however, the presence of aerosol particles ... Article in Journal/Newspaper Arctic Barrow Sea ice Alaska Max Planck Society: MPG.PuRe Arctic Atmospheric Chemistry and Physics 17 15 9291 9309 |
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Open Polar |
collection |
Max Planck Society: MPG.PuRe |
op_collection_id |
ftpubman |
language |
English |
description |
Heterogeneous photochemistry converts bromide (Br−) to reactive bromine species (Br atoms and bromine monoxide, BrO) that dominate Arctic springtime chemistry. This phenomenon has many impacts such as boundary-layer ozone depletion, mercury oxidation and deposition, and modification of the fate of hydrocarbon species. To study environmental controls on reactive bromine events, the BRomine, Ozone, and Mercury EXperiment (BROMEX) was carried out from early March to mid-April 2012 near Barrow (Utqiaġvik), Alaska. We measured horizontal and vertical gradients in BrO with multiple-axis differential optical absorption spectroscopy (MAX-DOAS) instrumentation at three sites, two mobile and one fixed. During the campaign, a large crack in the sea ice (an open lead) formed pushing one instrument package ∼ 250 km downwind from Barrow (Utqiaġvik). Convection associated with the open lead converted the BrO vertical structure from a surface-based event to a lofted event downwind of the lead influence. The column abundance of BrO downwind of the re-freezing lead was comparable to upwind amounts, indicating direct reactions on frost flowers or open seawater was not a major reactive bromine source. When these three sites were separated by ∼ 30 km length scales of unbroken sea ice, the BrO amount and vertical distributions were highly correlated for most of the time, indicating the horizontal length scales of BrO events were typically larger than ∼ 30 km in the absence of sea ice features. Although BrO amount and vertical distribution were similar between sites most of the time, rapid changes in BrO with edges significantly smaller than this ∼ 30 km length scale episodically transported between the sites, indicating BrO events were large but with sharp edge contrasts. BrO was often found in shallow layers that recycled reactive bromine via heterogeneous reactions on snowpack. Episodically, these surface-based events propagated aloft when aerosol extinction was higher (> 0.1 km−1); however, the presence of aerosol particles ... |
format |
Article in Journal/Newspaper |
author |
Simpson, W. Peterson, P. Friess, U. Sihler, H. Lampel, J. Platt, U. Moore, C. Pratt, K. Shepson, P. Halfacre, J. Nghiem, S. |
spellingShingle |
Simpson, W. Peterson, P. Friess, U. Sihler, H. Lampel, J. Platt, U. Moore, C. Pratt, K. Shepson, P. Halfacre, J. Nghiem, S. Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS |
author_facet |
Simpson, W. Peterson, P. Friess, U. Sihler, H. Lampel, J. Platt, U. Moore, C. Pratt, K. Shepson, P. Halfacre, J. Nghiem, S. |
author_sort |
Simpson, W. |
title |
Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS |
title_short |
Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS |
title_full |
Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS |
title_fullStr |
Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS |
title_full_unstemmed |
Horizontal and vertical structure of reactive bromine events probed by bromine monoxide MAX-DOAS |
title_sort |
horizontal and vertical structure of reactive bromine events probed by bromine monoxide max-doas |
publishDate |
2017 |
url |
http://hdl.handle.net/11858/00-001M-0000-002D-D393-C |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Barrow Sea ice Alaska |
genre_facet |
Arctic Barrow Sea ice Alaska |
op_source |
Atmospheric Chemistry and Physics |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/acp-17-9291-2017 http://hdl.handle.net/11858/00-001M-0000-002D-D393-C |
op_doi |
https://doi.org/10.5194/acp-17-9291-2017 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
17 |
container_issue |
15 |
container_start_page |
9291 |
op_container_end_page |
9309 |
_version_ |
1774715421598941184 |