Observations of I 2 at a remote marine site
Inorganic iodine plays a significant role in the photochemistry of the marine boundary layer, but the sources and cycling of iodine are not well understood. We report the first I 2 observations in marine air that is not impacted by coastal macroalgal emissions or sea ice chemistry. The data clearly...
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ftdoajarticles:oai:doaj.org/article:5481fffe44c7477c8b0e4daa034f1d1a 2023-05-15T18:18:38+02:00 Observations of I 2 at a remote marine site M. J. Lawler A. S. Mahajan A. Saiz-Lopez E. S. Saltzman 2014-03-01T00:00:00Z https://doi.org/10.5194/acp-14-2669-2014 https://doaj.org/article/5481fffe44c7477c8b0e4daa034f1d1a EN eng Copernicus Publications http://www.atmos-chem-phys.net/14/2669/2014/acp-14-2669-2014.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 doi:10.5194/acp-14-2669-2014 https://doaj.org/article/5481fffe44c7477c8b0e4daa034f1d1a Atmospheric Chemistry and Physics, Vol 14, Iss 5, Pp 2669-2678 (2014) Physics QC1-999 Chemistry QD1-999 article 2014 ftdoajarticles https://doi.org/10.5194/acp-14-2669-2014 2022-12-31T04:02:52Z Inorganic iodine plays a significant role in the photochemistry of the marine boundary layer, but the sources and cycling of iodine are not well understood. We report the first I 2 observations in marine air that is not impacted by coastal macroalgal emissions or sea ice chemistry. The data clearly demonstrate that the very high I 2 levels previously reported for coastal air are not representative of open ocean conditions. In this study, gas phase I 2 was measured at the Cape Verde Atmospheric Observatory, a semi-remote site in the eastern tropical Atlantic, using atmospheric pressure chemical ionization tandem mass spectrometry. Atmospheric I 2 levels typically increased beginning at sunset, leveled off after midnight, and then rapidly decreased at sunrise. There was also a smaller midday maximum in I 2 that was probably caused by a measurement artifact. Ambient I 2 mixing ratios ranged from <0.02–0.6 pmol mol −1 in May 2007 and <0.03–1.67 pmol mol −1 in May 2009. The sea-air flux implied by the nighttime buildup of I 2 is too small to explain the observed daytime IO levels at this site. Iodocarbon measurements made in this region previously are also insufficient to explain the observed 1–2 pmol mol −1 of daytime IO. The observations imply the existence of an unknown daytime source of gas phase inorganic iodine. Carpenter et al. (2013) recently proposed that sea surface emissions of HOI are several times larger than the flux of I 2 . Such a flux could account for both the nighttime I 2 and the daytime IO observations. Article in Journal/Newspaper Sea ice Directory of Open Access Journals: DOAJ Articles Atmospheric Chemistry and Physics 14 5 2669 2678 |
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Directory of Open Access Journals: DOAJ Articles |
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English |
topic |
Physics QC1-999 Chemistry QD1-999 |
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Physics QC1-999 Chemistry QD1-999 M. J. Lawler A. S. Mahajan A. Saiz-Lopez E. S. Saltzman Observations of I 2 at a remote marine site |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
Inorganic iodine plays a significant role in the photochemistry of the marine boundary layer, but the sources and cycling of iodine are not well understood. We report the first I 2 observations in marine air that is not impacted by coastal macroalgal emissions or sea ice chemistry. The data clearly demonstrate that the very high I 2 levels previously reported for coastal air are not representative of open ocean conditions. In this study, gas phase I 2 was measured at the Cape Verde Atmospheric Observatory, a semi-remote site in the eastern tropical Atlantic, using atmospheric pressure chemical ionization tandem mass spectrometry. Atmospheric I 2 levels typically increased beginning at sunset, leveled off after midnight, and then rapidly decreased at sunrise. There was also a smaller midday maximum in I 2 that was probably caused by a measurement artifact. Ambient I 2 mixing ratios ranged from <0.02–0.6 pmol mol −1 in May 2007 and <0.03–1.67 pmol mol −1 in May 2009. The sea-air flux implied by the nighttime buildup of I 2 is too small to explain the observed daytime IO levels at this site. Iodocarbon measurements made in this region previously are also insufficient to explain the observed 1–2 pmol mol −1 of daytime IO. The observations imply the existence of an unknown daytime source of gas phase inorganic iodine. Carpenter et al. (2013) recently proposed that sea surface emissions of HOI are several times larger than the flux of I 2 . Such a flux could account for both the nighttime I 2 and the daytime IO observations. |
format |
Article in Journal/Newspaper |
author |
M. J. Lawler A. S. Mahajan A. Saiz-Lopez E. S. Saltzman |
author_facet |
M. J. Lawler A. S. Mahajan A. Saiz-Lopez E. S. Saltzman |
author_sort |
M. J. Lawler |
title |
Observations of I 2 at a remote marine site |
title_short |
Observations of I 2 at a remote marine site |
title_full |
Observations of I 2 at a remote marine site |
title_fullStr |
Observations of I 2 at a remote marine site |
title_full_unstemmed |
Observations of I 2 at a remote marine site |
title_sort |
observations of i 2 at a remote marine site |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/acp-14-2669-2014 https://doaj.org/article/5481fffe44c7477c8b0e4daa034f1d1a |
genre |
Sea ice |
genre_facet |
Sea ice |
op_source |
Atmospheric Chemistry and Physics, Vol 14, Iss 5, Pp 2669-2678 (2014) |
op_relation |
http://www.atmos-chem-phys.net/14/2669/2014/acp-14-2669-2014.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 doi:10.5194/acp-14-2669-2014 https://doaj.org/article/5481fffe44c7477c8b0e4daa034f1d1a |
op_doi |
https://doi.org/10.5194/acp-14-2669-2014 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
14 |
container_issue |
5 |
container_start_page |
2669 |
op_container_end_page |
2678 |
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