Hughes, Claire orcid.org/0000-0002-9512-8052, Chuck, Adele L., Rossetti, Helen et al. (5 more authors) (2009) Seasonal cycle of seawater bromoform and dibromomethane concentrations in a coastal bay on the western Antarctic Peninsula. Global Biogeochemical Cycles. GB2024. pp. 1-13. ISSN 0886-6236
Abstract
Sea-to-air emissions of bromocarbon gases are known to play an important role in atmospheric ozone depletion. In this study, seawater concentrations of bromoform (CHBr3) and dibromomethane (CH2Br2) were measured regularly between February 2005 and March 2007 at the Rothera Oceanographic and Biological Time Series (RaTS) site located in Marguerite Bay on the Antarctic Peninsula. Strong seasonality in CHBr3 and CH2Br2 concentrations was observed. The highest bromocarbon concentrations (up to 276.4 ± 13.0 pmol CHBr3 L1 and 30.0 ± 0.4 pmol CH2Br2 L1) were found to coincide with the annual microalgal bloom during the austral summer, with lower concentrations (up to 39.5 pmol CHBr3 L1 and 9.6 ± 0.6 pmol CH2Br2 L1) measured under the winter fast ice. The timing of the initial increase in bromocarbon concentrations was related to the sea-ice retreat and onset of the microalgal bloom. Observed seasonal variability in CH2Br2/CHBr3 suggests that this relationship may be of use in resolving bromocarbon source regions. Mainly positive saturation anomalies calculated for both the 2005/2006 and 2006/2007 summers suggest that the bay was a source of CHBr3 and CH2Br2 to the atmosphere. Estimates of bromocarbon sea-to-air flux rates from Marguerite Bay during ice-free periods are 84 (13 to 275) CHBr3 nmol m2 d1 and 21 (2 to 70) nmol CH2Br2 m2 d1. If these flux rates are representative of the seasonal ice edge zone bloom which occurs each year over large areas of the Southern Ocean during the austral summer, sea-to-air bromocarbon emissions could have an important impact on the chemistry of the Antarctic atmosphere.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Environment and Geography (York) The University of York > Faculty of Sciences (York) > Chemistry (York) |
Depositing User: | Pure (York) |
Date Deposited: | 07 Jun 2012 17:31 |
Last Modified: | 16 Dec 2024 00:04 |
Published Version: | https://doi.org/10.1029/2008GB003268 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1029/2008GB003268 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:65906 |