EGUsphere EGUsphere EGUsphere EGUsphere Copernicus Publications Göttingen, Germany 10.5194/egusphere-2025-1467 Reviews and syntheses: Best practices for the application of marine GDGTs as proxy for paleotemperatures: sampling, processing, analyses, interpretation, and archiving protocols Bijl Peter K. https://orcid.org/0000-0002-1710-4012 1 22 Sliwinska Kasia K. https://orcid.org/0000-0001-5488-8832 2 22 Duncan Bella https://orcid.org/0000-0003-1108-6033 3 Huguet Arnaud https://orcid.org/0000-0002-6124-2922 4 Naeher Sebastian https://orcid.org/0000-0002-5336-6458 5 6 Rattanasriampaipong Ronnakrit https://orcid.org/0000-0002-1425-8737 7 8 Sosa-Montes de Oca Claudia https://orcid.org/0000-0003-4451-6458 9 Auderset Alexandra https://orcid.org/0000-0002-6316-4980 10 Berke Melissa https://orcid.org/0000-0003-4810-3773 11 Kim Bum Soo 12 13 Davtian Nina https://orcid.org/0000-0002-3047-6064 14 Dunkley Jones Tom https://orcid.org/0000-0002-9518-8143 15 Eefting Desmond 16 Elling Felix https://orcid.org/0000-0003-0405-4033 17 O'Connor Lauren 1 Pancost Richard D. 9 Peterse Francien https://orcid.org/0000-0001-8781-2826 1 Fenies Pierrick https://orcid.org/0000-0002-1183-9704 18 Rice Addison https://orcid.org/0000-0002-4507-6717 1 Sluijs Appy https://orcid.org/0000-0003-2382-0215 1 Varma Devika https://orcid.org/0000-0001-9707-6690 19 Xiao Wenjie https://orcid.org/0000-0002-4734-683X 20 Zhang Yige https://orcid.org/0000-0001-7331-1246 21 Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Utrecht, the Netherlands Geological Survey of Denmark and Greenland (GEUS), Department of geoenergy and storage, Copenhagen, Denmark Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand Sorbonne Université, CNRS, EPHE, PSL, UMR METIS, Paris, 75005, France GNS Science, Lower Hutt, New Zealand School of Geography, Environment and Earth Sciences, Victoria University of Wellington, Wellington, New Zealand University Corporation for Atmospheric Research, Boulder, CO, 80307 USA Department of Geosciences, The University of Arizona, Tucson, AZ, 85721 USA Organic Geochemistry Unit, School of Earth Sciences, School of Chemistry, The Cabot Institute for the Environment, University of Bristol, Bristol, UK School of Ocean and Earth Science, University of Southampton, Southampton SO14 3ZH, United Kingdom Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame IN 46556, USA Astromaterials Research and Exploration Science Division, NASA Johnson Space Center, Houston, TX 77058, USA Amentum, JSC Engineering and Technical Support (JETS) Contract, NASA Johnson Space Center, Houston, TX 77058, USA CEREGE, Aix-Marseille Université, CNRS, IRD, INRAE, Collège de France, Technopôle de l'Arbois, 13545 Aix-en-Provence, France School of Geography, Earth and Environmental Sciences, University of Birmingham, B15 2TT, United Kingdom GeoLab, Faculty of Geoscience, Utrecht University, Utrecht, the Netherlands Leibniz-Laboratory for Radiometric Dating and Isotope Research, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany Institute of Oceanography, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, 10617 Taipei, Taiwan Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Den Burg, the Netherlands Department of Biology, HADAL & Nordcee, University of Southern Denmark, 5230 Odense M, Denmark Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China These authors contributed equally to this work. 15 04 2025 2025 1 74 Copyright: © 2025 Peter K. Bijl et al. 2025 This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/ This article is available from https://egusphere.copernicus.org/preprints/2025/egusphere-2025-1467/ The full text article is available as a PDF file from https://egusphere.copernicus.org/preprints/2025/egusphere-2025-1467/egusphere-2025-1467.pdf

Marine glycerol dialkyl glycerol tetraethers (GDGTs) are used in various proxies (such as TEX<sub>86</sub>) to reconstruct past ocean temperatures. Over 20 years of improvements in GDGT sample processing, analytical techniques, data interpretation and our understanding of proxy functioning have led to the collective development of a set of best practices in all these areas. Further, the importance of Open Science in research has increased the emphasis on the systematic documentation of data generation, reporting and archiving processes for optimal reusability of data. In this paper, we provide protocols and best practices for obtaining, interpreting and presenting GDGT data (with a focus on marine GDGTs), from sampling to data archiving. The purpose of this paper is to optimize inter-laboratory comparability of GDGT data, and to ensure published data follows modern open access principles.

 Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung IZSEZ0 220372 Nederlandse Organisatie voor Wetenschappelijk Onderzoek work20232-1 192.074 Deutsche Forschungsgemeinschaft 441217575