ORCID
- Simon T. Belt: 0000-0002-1570-2924
Abstract
Two tri-unsaturated and isomeric (E/Z) highly branched isoprenoid (HBI) diatom lipid biomarkers were quantified in 228 water column samples collected from the English Channel, West Svalbard (Arctic), the Scotia Sea (Southern Ocean) and East Antarctica. We found that the relative amounts of the two HBIs correlate well with water temperatures taken at the time of sampling. Based on these findings and some other HBI data reported previously, we suggest that the proportion of the HBI E-isomer (termed EZ25) may serve as a new proxy for palaeo sea surface temperatures, including in the polar regions. Next steps will involve determination of EZ25 in surface and downcore sediments to ascertain whether the temperature response described herein translates well to the geological record.
DOI Link
Publication Date
2025-08-18
Publication Title
Organic Geochemistry
Volume
208
ISSN
0146-6380
Acceptance Date
2025-08-15
Deposit Date
2026-01-07
Funding
This work was supported by the Leverhulme Trust (UK; RPG-2015-439) and the Natural Environment Research Council (UK; NE/X009416/1). We thank Katrin Schmidt and Claire Widdicombe for some data acquisition and sample collection, and to two anonymous reviewers and the Editors for providing helpful feedback on the original manuscript. We dedicate this paper in memory of Leanne Armand (Australian National University) who provided some of the Antarctic water samples.
Additional Links
Keywords
Biomarker, Sea surface temperature, Proxy, Arctic, Antarctic, Highly branched isoprenoid, HBI
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Belt, S., Smik, L., Husum, K., & Knies, J. (2025) 'A potential new sea surface temperature proxy based on isomeric highly branched isoprenoid lipid biomarkers: EZ25', Organic Geochemistry, 208. Available at: 10.1016/j.orggeochem.2025.105056
