Abstract:
This dataset provides information on the annual abundance and seasonal concentration of diatoms preserved in firn layers from the sub-Antarctic Bouvet Island firn core that was drilled in 2017. The diatom record represents the interval from austral winter 2000 CE to austral winter 2015 CE. Meltwater from the annual layers of the firn core was filtered, and the filters were analyzed using a Scanning Electron Microscope for the identification and classification of diatoms. This dataset presents three diatom records: "total", "SIDI" and "n-SIDI". The "total" diatom record corresponds to all diatoms counted in the Bouvet Island samples. The "SIDI" and "n-SIDI" are subsets of the "total" record. The "SIDI" (Sea Ice Diatom Index) diatom record is the sum of the sea ice diatoms in Bouvet Island samples: Fragilariopsis cylindrus and F. curta. The "n-SIDI" (non-Sea Ice Diatom Index) represent the sum of all diatoms found in Bouvet Island samples which are not sea ice diatoms. The "total", "SIDI" and "n-SIDI" diatom records were utilized to reconstruct changes in the westerly winds of the Southern Hemisphere, with the results presented in Tetzner et al (2026).
Funding for drilling the Bouvet Island firn core (subICE project) was awarded to Elizabeth R. Thomas by Ecole Polytechnique Federale de Lausanne (EPFL); Swiss Polar Institute (SPI); Ferring Pharmaceuticals
Keywords:
Antarctica, Southern Hemisphere Westerly Winds, diatoms, ice core, sea ice, sub-Antarctic
Tetzner, D., Allen, C., & Thomas, E. (2026). Annual diatom abundance and seasonal diatom concentration from the Bouvet Island firn core, Antarctic Peninsula, 2000-2015 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/a6a1aa67-c906-4887-8983-8ef07897a74e
| Access Constraints: | None |
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| Use Constraints: | This data is governed by the NERC data policy (http://www.nerc.ac.uk/research/sites/data/policy/) and supplied under Open Government Licence v.3 (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/). |
| Creation Date: | 2026-03-12 |
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| Dataset Progress: | Planned |
| Dataset Language: | English |
| ISO Topic Categories: |
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| Parameters: |
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| Personnel: | |
| Name | UK Polar Data Centre |
| Role(s) | Metadata Author |
| Organisation | British Antarctic Survey |
| Name | Dieter Tetzner |
| Role(s) | Investigator, Technical Contact |
| Organisation | British Antarctic Survey |
| Name | Claire Allen |
| Role(s) | Investigator |
| Organisation | British Antarctic Survey |
| Name | Elizabeth R Thomas |
| Role(s) | Investigator |
| Organisation | British Antarctic Survey |
| Parent Dataset: | N/A |
| Reference: | Armand, L. K., Crosta, X., Romero, O., and Pichon, J. J. (2005). The biogeography of major diatom taxa in Southern Ocean sediments: 1. Sea ice related species. Palaeogeogr. Palaeoclimatol. Palaeoecol. 223 (1-2). https://doi.org/10.1016/j.palaeo.2005.02.015 Cefarelli, A. O., Ferrario, M. E., Almandoz, G. O., Atencio, A. G., Akselman, R., and Vernet, M. (2010). Diversity of the diatom genus Fragilariopsis in the Argentine Sea and Antarctic waters: morphology, distribution and abundance. Polar Biol. 33 (11), 1463-1484. https://doi.org/10.1007/s00300-010-0794-z Hasle, G. R., & Syvertsen, E. E. (1997). Identifying Marine Phytoplankton. Academic Press, London. https://doi.org/10.1016/B978-0-12-693018-4.X5000-9 Tetzner, D., Thomas, E. R., Allen, C. S., & Wolff, E. W. (2021). A refined method to analyze insoluble particulate matter in ice cores, and its application to diatom sampling in the Antarctic Peninsula. Frontiers in Earth Science, 9, 617043. https://doi.org/10.3389/feart.2021.617043 Tetzner, D. R., Allen, C. S., Thomas, E. R., & Humby, J. (2025). Use of excess meltwater from continuous flow analysis systems for the analysis of low concentration insoluble microparticles in ice cores. Frontiers in Earth Science, 13, 1530875. https://doi.org/10.3389/feart.2025.1530875 Tetzner, D. R.; Thomas, E. R.; Allen, C. S.; Segato, D.; Miller, S. (in review). Windblown Diatoms for Reconstructing Westerly Wind Variability in the South Atlantic Sector of the Southern Ocean. Geophysical Research Letters. Zielinski, U., and Gersonde, R. (1997). Diatom distribution in Southern Ocean surface sediments (Atlantic sector): implications for paleoenvironmental reconstructions. Palaeogeogr. Palaeoclimatol. Palaeoecol. 129 (3-4), 213-250. https://doi.org/10.1016/S0031-0182(96)00130-7 |
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| Quality: | Diatom samples were processed and analysed according to the methods and constraints outlined in Tetzner et al. (2021) and Tetzner et al. (2025). Annual layer meltwater from Bouvet Island firn core was filtered using polycarbonate membrane filters with a pore diameter of 1.0 micro-meter. After filtration, the filters were scanned using a Scanning Electron Microscope (SEM). One-third of the filter area was scanned, in line with the observations from Tetzner et al. (2021) and Tetzner et al. (2025), which noted that diatoms tend to have a homogeneous spatial distribution when the counts over one-third of the filter area are six or more. | |
| Lineage/Methodology: | The Bouvet Island firn core was drilled in March 2017 CE to a depth of 14.2 meters using a Kovacs Coring System. An ice chronology was established based on annual cycles of stable water isotopes and major ions. Diatom samples were obtained by filtering meltwater from annual layers of the Bouvet Island firn core. Bouvet Island firn core meltwater was filtered through 1.0 micro-meter pore size filters, which were later imaged using a Quanta-650F Scanning Electron Microscope (SEM) at the Earth Sciences Department, University of Cambridge. Diatom identification and ecological associations were based on published Southern Ocean databases and references therein (Armand et al., 2005; Hasle and Syvertsen, 1997; Cefarelli et al., 2010; Zielinski and Gersonde, 1997). | |
| Temporal Coverage: | |
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| Start Date | 2017-03-01 |
| End Date | 2017-03-31 |
| Paleo Temporal Coverage: | |
| Paleo Start Date | 2000 CE |
| Paleo End Date | 2015 CE |
| Chronostratigraphic Unit | N/A |
| Spatial Coverage: | |
| Latitude | |
| Southernmost | -54.42 |
| Northernmost | -54.42 |
| Longitude | |
| Westernmost | 3.37 |
| Easternmost | 3.37 |
| Altitude | |
| Min Altitude | 350 |
| Max Altitude | 350 |
| Depth | |
| Min Depth | N/A |
| Max Depth | N/A |
| Location: | |
| Location | Bouvet Island |
| Detailed Location | N/A |
| Data Collection: | Annual diatom samples were obtained through filtration. Filters were later imaged using a Scanning Electron Microscope following the method and constraints presented in Tetzner et al. (2021) |
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| Data Storage: | 4 x .csv files "Diatom abundance" dataset is presented at annual resolution (2000-2015 CE), with each year running from austral mid-winter to mid-winter. "Total diatom concentration_seasonal", "SIDI diatom concentration_seasonal" and "n-SIDI diatom concentration_seasonal" datasets are presented at seasonal resolution for selected years, with each year running from austral mid-winter to mid-winter. "Total diatom concentration_seasonal", "SIDI diatom concentration_seasonal" and "n-SIDI diatom concentration_seasonal" datasets present seasons as: JFM=January-February-March; AMJ=April-May-June; JAS=July-August-September; OND=October-November-December. |
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