Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8
Atmospheric Mercury Depletion Events (MDEs) in Arctic springtime were investigated utilizing a box model based on airborne measurements from the NASA DC-8 during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Measurements showed that M...
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ftcopernicus:oai:publications.copernicus.org:acpd3229 2023-05-15T14:48:11+02:00 Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8 Kim, S. Y. Talbot, R. Mao, H. Blake, D. R. Huey, G. Weinheimer, A. J. 2018-08-10 application/pdf https://doi.org/10.5194/acpd-10-10077-2010 https://www.atmos-chem-phys-discuss.net/acp-2010-162/ eng eng doi:10.5194/acpd-10-10077-2010 https://www.atmos-chem-phys-discuss.net/acp-2010-162/ eISSN: 1680-7324 Text 2018 ftcopernicus https://doi.org/10.5194/acpd-10-10077-2010 2019-12-24T09:57:25Z Atmospheric Mercury Depletion Events (MDEs) in Arctic springtime were investigated utilizing a box model based on airborne measurements from the NASA DC-8 during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Measurements showed that MDEs occurred near the surface and always over the Arctic Ocean accompanied by concurrent ozone (O 3 ) depletion, enhancement in Br 2 mixing ratios, and decreases in ethyne and light weight alkanes. Backward trajectories indicated that most air masses inside the MDEs originated at low altitude over the ocean presumably generating a halogen-rich environment. We developed a box model which considered only gas phase reactions of mercury, halogen species, and O 3 chemistry. We conducted a series of sensitivity simulations to determine the factors that are of most importance to MDE formation. The box model results suggested that continuous enhancement of Br 2 mixing ratios, a high intensity of solar radiation, or a relatively high NO x regime expedited Hg° depletion. These environments generated high concentrations of Br radical, and thus the model results indicated that the Br radical was very important for Hg° depletion. Utilizing different rate constants for reaction of Hg° + Br produced times to reach Hg° depletion ranging from 22 to 32 h. Text Arctic Arctic Ocean Copernicus Publications: E-Journals Arctic Arctic Ocean |
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Copernicus Publications: E-Journals |
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English |
description |
Atmospheric Mercury Depletion Events (MDEs) in Arctic springtime were investigated utilizing a box model based on airborne measurements from the NASA DC-8 during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Measurements showed that MDEs occurred near the surface and always over the Arctic Ocean accompanied by concurrent ozone (O 3 ) depletion, enhancement in Br 2 mixing ratios, and decreases in ethyne and light weight alkanes. Backward trajectories indicated that most air masses inside the MDEs originated at low altitude over the ocean presumably generating a halogen-rich environment. We developed a box model which considered only gas phase reactions of mercury, halogen species, and O 3 chemistry. We conducted a series of sensitivity simulations to determine the factors that are of most importance to MDE formation. The box model results suggested that continuous enhancement of Br 2 mixing ratios, a high intensity of solar radiation, or a relatively high NO x regime expedited Hg° depletion. These environments generated high concentrations of Br radical, and thus the model results indicated that the Br radical was very important for Hg° depletion. Utilizing different rate constants for reaction of Hg° + Br produced times to reach Hg° depletion ranging from 22 to 32 h. |
format |
Text |
author |
Kim, S. Y. Talbot, R. Mao, H. Blake, D. R. Huey, G. Weinheimer, A. J. |
spellingShingle |
Kim, S. Y. Talbot, R. Mao, H. Blake, D. R. Huey, G. Weinheimer, A. J. Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8 |
author_facet |
Kim, S. Y. Talbot, R. Mao, H. Blake, D. R. Huey, G. Weinheimer, A. J. |
author_sort |
Kim, S. Y. |
title |
Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8 |
title_short |
Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8 |
title_full |
Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8 |
title_fullStr |
Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8 |
title_full_unstemmed |
Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8 |
title_sort |
chemical transformations of hg° during arctic mercury depletion events sampled from the nasa dc-8 |
publishDate |
2018 |
url |
https://doi.org/10.5194/acpd-10-10077-2010 https://www.atmos-chem-phys-discuss.net/acp-2010-162/ |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Ocean |
genre_facet |
Arctic Arctic Ocean |
op_source |
eISSN: 1680-7324 |
op_relation |
doi:10.5194/acpd-10-10077-2010 https://www.atmos-chem-phys-discuss.net/acp-2010-162/ |
op_doi |
https://doi.org/10.5194/acpd-10-10077-2010 |
_version_ |
1766319276561530880 |