Brown, Lucy V., Pound, Ryan J. orcid.org/0000-0003-1547-6565, Jones, Matthew R. orcid.org/0000-0001-8077-2331 et al. (18 more authors) (2025) Iodine speciation in snow during the MOSAiC expedition and its implications for Arctic iodine emissions. FARADAY DISCUSSIONS. ISSN 1364-5498
Abstract
Photochemical release of iodine from snow has been suggested as a source of reactive iodine to the Arctic atmosphere, however understanding of the underlying mechanism and potential source strength is hindered by a lack of measurements of iodine concentration and speciation in snow. Moreover, the origin of snow iodine is also unknown. Here, we report iodine speciation measurements in Arctic snow on sea ice at a range of snow depths from 177 samples, representing 80 sampling events, from December 2019 to October 2020 collected during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. We demonstrate that while there appears to be a source of iodine, in particular iodate, to the base of the snow over first year ice, this does not influence iodine concentration in the surface snow. There is instead evidence of a top-down source of iodine, potentially from iodine-enriched marine aerosol, as well as some evidence for episodic influx of iodate with dust. The potential for photochemical release of molecular iodine (I2) from iodide in surface snow was investigated, and it was demonstrated that this could provide an iodine emission flux to the Arctic atmosphere comparable to oceanic fluxes. Knowledge of the prevalence and speciation of iodine in Arctic snow will contribute to better understanding of its contribution to observed concentrations of polar iodine oxide (IO), and hence its contribution to the depletion of tropospheric ozone in the Arctic.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Royal Society of Chemistry 2025 |
Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Chemistry (York) The University of York > Faculty of Arts and Humanities (York) > Archaeology (York) |
Depositing User: | Pure (York) |
Date Deposited: | 07 Mar 2025 14:10 |
Last Modified: | 15 Apr 2025 01:36 |
Published Version: | https://doi.org/10.1039/D4FD00178H |
Status: | Published online |
Refereed: | Yes |
Identification Number: | 10.1039/D4FD00178H |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:224201 |
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Description: Iodine speciation in snow during the MOSAiC expedition and its implications for Arctic iodine emissions
Licence: CC-BY-NC 2.5