Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble
During long-range transport, many distinct processes – including photochemistry, deposition, emissions and mixing – contribute to the transformation of air mass composition. Partitioning the effects of different processes can be useful when considering the sensitivity of chemical transformation to,...
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ftdoajarticles:oai:doaj.org/article:03a6a56c9fb848c78857d70b6c5d3552 2023-05-15T17:36:04+02:00 Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble M. Cain J. Methven E. J. Highwood 2012-08-01T00:00:00Z https://doi.org/10.5194/acp-12-7015-2012 https://doaj.org/article/03a6a56c9fb848c78857d70b6c5d3552 EN eng Copernicus Publications http://www.atmos-chem-phys.net/12/7015/2012/acp-12-7015-2012.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-12-7015-2012 1680-7316 1680-7324 https://doaj.org/article/03a6a56c9fb848c78857d70b6c5d3552 Atmospheric Chemistry and Physics, Vol 12, Iss 15, Pp 7015-7039 (2012) Physics QC1-999 Chemistry QD1-999 article 2012 ftdoajarticles https://doi.org/10.5194/acp-12-7015-2012 2022-12-31T09:21:52Z During long-range transport, many distinct processes – including photochemistry, deposition, emissions and mixing – contribute to the transformation of air mass composition. Partitioning the effects of different processes can be useful when considering the sensitivity of chemical transformation to, for example, a changing environment or anthropogenic influence. However, transformation is not observed directly, since mixing ratios are measured, and models must be used to relate changes to processes. Here, four cases from the ITCT-Lagrangian 2004 experiment are studied. In each case, aircraft intercepted a distinct air mass several times during transport over the North Atlantic, providing a unique dataset and quantifying the net changes in composition from all processes. A new framework is presented to deconstruct the change in O 3 mixing ratio (Δ O 3 ) into its component processes, which were not measured directly, taking into account the uncertainty in measurements, initial air mass variability and its time evolution. The results show that the net chemical processing (Δ O 3chem ) over the whole simulation is greater than net physical processing (Δ O 3phys ) in all cases. This is in part explained by cancellation effects associated with mixing. In contrast, each case is in a regime of either net photochemical destruction (lower tropospheric transport) or production (an upper tropospheric biomass burning case). However, physical processes influence O 3 indirectly through addition or removal of precursor gases, so that changes to physical parameters in a model can have a larger effect on Δ O 3chem than Δ O 3phys . Despite its smaller magnitude, the physical processing distinguishes the lower tropospheric export cases, since the net photochemical O 3 change is −5 ppbv per day in all three cases. Processing is quantified using a Lagrangian photochemical model with a novel method for simulating mixing through an ensemble of trajectories and a background profile that evolves with them. The model is able to simulate the ... Article in Journal/Newspaper North Atlantic Directory of Open Access Journals: DOAJ Articles Atmospheric Chemistry and Physics 12 15 7015 7039 |
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Physics QC1-999 Chemistry QD1-999 |
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Physics QC1-999 Chemistry QD1-999 M. Cain J. Methven E. J. Highwood Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
During long-range transport, many distinct processes – including photochemistry, deposition, emissions and mixing – contribute to the transformation of air mass composition. Partitioning the effects of different processes can be useful when considering the sensitivity of chemical transformation to, for example, a changing environment or anthropogenic influence. However, transformation is not observed directly, since mixing ratios are measured, and models must be used to relate changes to processes. Here, four cases from the ITCT-Lagrangian 2004 experiment are studied. In each case, aircraft intercepted a distinct air mass several times during transport over the North Atlantic, providing a unique dataset and quantifying the net changes in composition from all processes. A new framework is presented to deconstruct the change in O 3 mixing ratio (Δ O 3 ) into its component processes, which were not measured directly, taking into account the uncertainty in measurements, initial air mass variability and its time evolution. The results show that the net chemical processing (Δ O 3chem ) over the whole simulation is greater than net physical processing (Δ O 3phys ) in all cases. This is in part explained by cancellation effects associated with mixing. In contrast, each case is in a regime of either net photochemical destruction (lower tropospheric transport) or production (an upper tropospheric biomass burning case). However, physical processes influence O 3 indirectly through addition or removal of precursor gases, so that changes to physical parameters in a model can have a larger effect on Δ O 3chem than Δ O 3phys . Despite its smaller magnitude, the physical processing distinguishes the lower tropospheric export cases, since the net photochemical O 3 change is −5 ppbv per day in all three cases. Processing is quantified using a Lagrangian photochemical model with a novel method for simulating mixing through an ensemble of trajectories and a background profile that evolves with them. The model is able to simulate the ... |
format |
Article in Journal/Newspaper |
author |
M. Cain J. Methven E. J. Highwood |
author_facet |
M. Cain J. Methven E. J. Highwood |
author_sort |
M. Cain |
title |
Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble |
title_short |
Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble |
title_full |
Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble |
title_fullStr |
Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble |
title_full_unstemmed |
Quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble |
title_sort |
quantification of chemical and physical processes influencing ozone during long-range transport using a trajectory ensemble |
publisher |
Copernicus Publications |
publishDate |
2012 |
url |
https://doi.org/10.5194/acp-12-7015-2012 https://doaj.org/article/03a6a56c9fb848c78857d70b6c5d3552 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Atmospheric Chemistry and Physics, Vol 12, Iss 15, Pp 7015-7039 (2012) |
op_relation |
http://www.atmos-chem-phys.net/12/7015/2012/acp-12-7015-2012.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-12-7015-2012 1680-7316 1680-7324 https://doaj.org/article/03a6a56c9fb848c78857d70b6c5d3552 |
op_doi |
https://doi.org/10.5194/acp-12-7015-2012 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
12 |
container_issue |
15 |
container_start_page |
7015 |
op_container_end_page |
7039 |
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1766135438866644992 |