MArine radioCArbon Reservoir Alter (MARCARA)
Funding programm: Deutsche Forschungsgemeinschaft (DFG)
Funding identification number (FZK): DFG LO 895/20-1 via Uni Bremen
Cost (Kostenstelle): via Uni Bremen
Project term: 01 July 2022 - 30 June 2025
Applicants: Prof. Dr. Gerrit Lohmann | Dr. Martin Butzin | Prof. Dr. Edouard Bard
We reconstruct the distribution of radiocarbon at the sea surface with unprecedented temporal and spatial resolution and simulate it using a novel multi-scale climate radiocarbon model. This will allow marine data to be corrected and hypotheses about abrupt climate changes during the last ice age to be tested.
The Marine Reservoir Effect in C-14 is a phenomenon that works as a proxy for several climate-related parameters. Still, the MRE remains understudied in many locations around the globe, limiting our understanding of the global carbon cycle and how it responds to climate change. Taking advantage of the state-of-the-art facilities available in the host institutions, the investigators will be able to achieve high-quality data that are much needed at this moment of profound changes in climate. Indeed, by providing the quantification of the MRE for key locations in the main ocean basins, the MARCARA project aims to fill a long-standing gap in radiocarbon research. The project combines both experimental data acquired in the lab with numerical modelling, which is a powerful combination that will strengthen the outcomes of the project. This type of approach has been successfully used in climate research and remains crucial for the understanding of climate evolution in different timescales. Focusing on the last deglacial, which is a key period for understanding the Earth Climate System, the project is an ambitious undertaking that has the potential to enhance our knowledge of the climate system stimulating new research on a variety of topics, ranging from archaeology and cultural heritage to the geosciences. By providing these data, the MARCARA project is likely to positively impact the radiocarbon community helping to unravel the mechanisms involved in climate variations over the past.
(a) Atmospheric radiocarbon concentrations in terms of F14C (the fractionation-corrected and normalized 14C/12C ratio) according to the Hulu Cave speleothem record (Cheng et al., 2018; Southon et al., 2012). Upper and lower curves span the uncertainty range (mean values ±2σ).
(b) Ensemble simulations of marine 14C for the past 50 kyr forced with atmospheric F14C according to Hulu Cave, shown is the period where 14C dating is not further constrained through continuous tree ring 14C records.
(c) Corresponding ensemble simulations of marine 14C expressed as 14C age with respect to the contemporaneous atmosphere (the Marine Reservoir Age); values are averaged between 50°N and 50°S. CS, GS, and PD specify different ocean states with weak, intermediate, and strong overturning (Butzin et al., 2020).
(d) Marine reservoir age simulated for the Last Glacial Maximum; shown is the ensemble median of the transient simulations. Filled circles are foraminifera-based marine reservoir ages compiled by Skinner et al. (2017).
More Informationen about MARCARA
References
Lohmann, G., M. Butzin, N. Eissner, X. Shi, C. Stepanek, 2020: Abrupt climate and weather changes across timescales. Paleoceanography and Paleoclimatology 35 (9), e2019PA003782, DOI:10.1029/2019PA003782, Special Section AGU Grand Challenges in the Earth and Space Sciences. (link to PANGAEA) (link to AWI-ESM) (news) (top cited) (pdf) (link)
Butzin, M., Ye, Y., Völker, C., Gürses, Ö., Hauck, J., and Köhler, P.: Carbon isotopes in the marine biogeochemistry model FESOM2.1-REcoM3, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2023-1718, 2023. Accepted for publication in Geoscientific Model Development on 9 January 2024
Ye, Y., Munhoven, G., Köhler, P., Butzin, M., Hauck, J., Gürses, Ö., and Völker, C.: FESOM2.1-REcoM3-MEDUSA2: an ocean-sea ice-biogeochemistry model coupled to a sediment model, Geosci. Model Dev. Discuss. [preprint], https://doi.org/10.5194/gmd-2023-181, 2023. (in revision)
Beisel, E., Frank, N., Robinson, L. F., Lausecker, M., Friedrich, R., Therre, S., Schröder-Ritzrau, A., Butzin, M. (2023).: Climate induced thermocline aging and ventilation in the eastern Atlantic over the last 32,000 years. Paleoceanography and Paleoclimatology, 38, e2023PA004662. https://doi.org/10.1029/2023PA004662 https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023PA004662
Heaton, T.J., Butzin, M., Bard, E., Bronk Ramsey, C., Hughen, K.A., Köhler, P., Reimer, P.J.: MARINE RADIOCARBON CALIBRATION IN POLAR REGIONS: A SIMPLE APPROXIMATE APPROACH USING MARINE20. Radiocarbon, 2023;65(4):848-875. doi:10.1017/RDC.2023.42
Ruben, M., Hefter, J., Schubotz, F., Geibert, W., Butzin, M., Gentz, T., Grotheer, H., Forwick, M., Szczuciński, W., Mollenhauer, G.: Fossil organic carbon utilization in marine Arctic fjord sediments by subsurface micro-organisms. Nature Geoscience, 16, 625–630 (2023). https://doi.org/10.1038/s41561-023-01198-z
Butzin, M. Köhler, P., Lohmann, G.: Prospects and limitations of marine radiocarbon simulations in (paleo) climate studies 24th Radiocarbon and the 10th Radiocarbon & Archaeology Conferences, Zürich, 11 – 16 September 2022 (invited talk)
Butzin, M., Köhler, P., Völker, C., Ye, Y., and Lohmann, G.: How accurate are marine Δ14CDIC modelling approaches?, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-1481, https://doi.org/10.5194/egusphere-egu23-1481, 2023 (talk).