Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere
The role of halogen species (e.g., Br, Cl) in the troposphere of polar regions has been investigated since the discovery of their importance for boundary layer ozone destruction in the polar spring about 25 years ago. Halogen species take part in an auto-catalytic chemical reaction cycle, which rele...
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ftdoajarticles:oai:doaj.org/article:4ffdf483dba84b8baa21b520cd0dee0c 2023-05-15T18:18:56+02:00 Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere L. Cao H. Sihler U. Platt E. Gutheil 2014-04-01T00:00:00Z https://doi.org/10.5194/acp-14-3771-2014 https://doaj.org/article/4ffdf483dba84b8baa21b520cd0dee0c EN eng Copernicus Publications http://www.atmos-chem-phys.net/14/3771/2014/acp-14-3771-2014.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 doi:10.5194/acp-14-3771-2014 https://doaj.org/article/4ffdf483dba84b8baa21b520cd0dee0c Atmospheric Chemistry and Physics, Vol 14, Iss 7, Pp 3771-3787 (2014) Physics QC1-999 Chemistry QD1-999 article 2014 ftdoajarticles https://doi.org/10.5194/acp-14-3771-2014 2022-12-31T13:21:06Z The role of halogen species (e.g., Br, Cl) in the troposphere of polar regions has been investigated since the discovery of their importance for boundary layer ozone destruction in the polar spring about 25 years ago. Halogen species take part in an auto-catalytic chemical reaction cycle, which releases Br 2 and BrCl from the sea salt aerosols, fresh sea ice or snowpack, leading to ozone depletion. In this study, three different chemical reaction schemes are investigated: a bromine-only reaction scheme, which then is subsequently extended to include nitrogen-containing compounds and chlorine species and corresponding chemical reactions. The importance of specific reactions and their rate constants is identified by a sensitivity analysis. The heterogeneous reaction rates are parameterized by considering the aerodynamic resistance, a reactive surface ratio, β, i.e., the ratio of reactive surface area to total ground surface area, and the boundary layer height, L mix . It is found that for β = 1, a substantial ozone decrease occurs after five days and ozone depletion lasts for 40 h for L mix = 200 m. For about β ≥ 20, the time required for major ozone depletion ([O 3 ] < 4 ppb) to occur becomes independent of the height of the boundary layer, and for β = 100 it approaches two days, 28 h of which are attributable to the induction and 20 h to the depletion time. In polar regions, a small amount of NO x may exist, which stems from nitrate contained in the snow, and may have a strong impact on the ozone depletion. Therefore, the role of nitrogen-containing species on the ozone depletion rate is studied. The results show that the NO x concentrations are influenced by different chemical reactions over different time periods. During ozone depletion, the reaction cycle involving the BrONO 2 hydrolysis is dominant. A critical value of 0.0004 of the uptake coefficient of the BrONO 2 hydrolysis reaction at the aerosol and saline surfaces is identified, beyond which the existence of NO x species accelerates the ozone ... Article in Journal/Newspaper Sea ice Directory of Open Access Journals: DOAJ Articles Atmospheric Chemistry and Physics 14 7 3771 3787 |
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Physics QC1-999 Chemistry QD1-999 |
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Physics QC1-999 Chemistry QD1-999 L. Cao H. Sihler U. Platt E. Gutheil Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
The role of halogen species (e.g., Br, Cl) in the troposphere of polar regions has been investigated since the discovery of their importance for boundary layer ozone destruction in the polar spring about 25 years ago. Halogen species take part in an auto-catalytic chemical reaction cycle, which releases Br 2 and BrCl from the sea salt aerosols, fresh sea ice or snowpack, leading to ozone depletion. In this study, three different chemical reaction schemes are investigated: a bromine-only reaction scheme, which then is subsequently extended to include nitrogen-containing compounds and chlorine species and corresponding chemical reactions. The importance of specific reactions and their rate constants is identified by a sensitivity analysis. The heterogeneous reaction rates are parameterized by considering the aerodynamic resistance, a reactive surface ratio, β, i.e., the ratio of reactive surface area to total ground surface area, and the boundary layer height, L mix . It is found that for β = 1, a substantial ozone decrease occurs after five days and ozone depletion lasts for 40 h for L mix = 200 m. For about β ≥ 20, the time required for major ozone depletion ([O 3 ] < 4 ppb) to occur becomes independent of the height of the boundary layer, and for β = 100 it approaches two days, 28 h of which are attributable to the induction and 20 h to the depletion time. In polar regions, a small amount of NO x may exist, which stems from nitrate contained in the snow, and may have a strong impact on the ozone depletion. Therefore, the role of nitrogen-containing species on the ozone depletion rate is studied. The results show that the NO x concentrations are influenced by different chemical reactions over different time periods. During ozone depletion, the reaction cycle involving the BrONO 2 hydrolysis is dominant. A critical value of 0.0004 of the uptake coefficient of the BrONO 2 hydrolysis reaction at the aerosol and saline surfaces is identified, beyond which the existence of NO x species accelerates the ozone ... |
format |
Article in Journal/Newspaper |
author |
L. Cao H. Sihler U. Platt E. Gutheil |
author_facet |
L. Cao H. Sihler U. Platt E. Gutheil |
author_sort |
L. Cao |
title |
Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere |
title_short |
Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere |
title_full |
Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere |
title_fullStr |
Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere |
title_full_unstemmed |
Numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere |
title_sort |
numerical analysis of the chemical kinetic mechanisms of ozone depletion and halogen release in the polar troposphere |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/acp-14-3771-2014 https://doaj.org/article/4ffdf483dba84b8baa21b520cd0dee0c |
genre |
Sea ice |
genre_facet |
Sea ice |
op_source |
Atmospheric Chemistry and Physics, Vol 14, Iss 7, Pp 3771-3787 (2014) |
op_relation |
http://www.atmos-chem-phys.net/14/3771/2014/acp-14-3771-2014.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 doi:10.5194/acp-14-3771-2014 https://doaj.org/article/4ffdf483dba84b8baa21b520cd0dee0c |
op_doi |
https://doi.org/10.5194/acp-14-3771-2014 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
14 |
container_issue |
7 |
container_start_page |
3771 |
op_container_end_page |
3787 |
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1766195711099011072 |