Isotope and climate variability since the last deglaciation

Funding programm: Bundesministerium für Bildung und Forschung
Funding identification number (FZK): 01LP2309A
Cost (Kostenstelle): DM 87011020
Project duration:January 01 2024 - December 31 2026
Applicant: PD Dr. Martin Werner
PostDoc:    Dr. Yuchen Sun

 

The overall aim of this project is to investigate in detail the modelled and recorded water isotope changes during and after the last deglacial phase. The central question of our study is whether AWI-ESM, which has been enhanced by an explicit isotope diagnostic, can correctly reproduce important spatial and temporal features in the different isotope signals as recorded in paleo-archives during this period. This isotope modelling, which has already been successfully carried out in PalMod phases I/II, enables a direct model comparison of simulated isotope changes in different water compartments. Detailed analyses of the model results will help to identify both the most important climate processes that have driven water isotope changes in the past and possible model-dependent deficits in the simulation of the Earth's water cycle.

Trend evolution of the AMOC

Trend evolution in the three 16 ka BP experiments with a transient weakening of the AMOC. a) AMOC index (Sv) on the corresponding experiment time scales. The arrow marks the period which is used to calculate the composite trend in b) to e). b) precipitation minus evaporation (mm mon−1 ka−1), c) sea surface temperature (SST, °C ka−1), d) sea surface salinity (SSS, psu ka−1) and e) sea surface density (kg m−3 ka−1). c) to e) contain as an inlet plot the vertical profiles over the index region NENA as defined by the red rectangle in panel c). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

References

Cauquoin, A., Abe-Ouchi, A., Obase, T., Chan, W.-L., Paul, A., & Werner, M. (2023). Effects of Last Glacial Maximum (LGM) sea surface temperature and sea ice extent on the isotope–temperature slope at polar ice core sites. Climate of the Past, 19(6), 1275–1294. https://doi.org/10.5194/cp-19-1275-2023

Shi, X., Cauquoin, A., Lohmann, G., Jonkers, L., Wang, Q., Yang, H. et al. (2023). Simulated stable water isotopes during the mid-Holocene and pre-industrial periods using AWI-ESM-2.1-wiso. Geoscientific Model Development, 16(17), 5153–5178. https://doi.org/10.5194/gmd-16-5153-2023 

Sun, Y., Knorr, G., Zhang, X., Tarasov, L., Barker, S., Werner, M. et al. (2022). Ice sheet decline and rising atmospheric CO2 control AMOC sensitivity to deglacial meltwater discharge. Global and Planetary Change, 210103755. https://doi.org/10.1016/j.gloplacha.2022.103755 

Werner, M., Jouzel, J., Masson-Delmotte, V., & Lohmann, G. (2018). Reconciling glacial Antarctic water stable isotopes with ice sheet topography and the isotopic paleothermometer. Nature Communications, 9(1), 3537. https://doi.org/10.1038/s41467-018-05430-y