Articles | Volume 21, issue 6
https://doi.org/10.5194/cp-21-973-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/cp-21-973-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Mean ocean temperature change and decomposition of the benthic δ18O record over the past 4.5 million years
College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA
School of Geography and Environmental Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK
Invited contribution by Peter U. Clark, recipient of the EGU Milutin Milanković Medal 2024.
Jeremy D. Shakun
Department of Earth and Environmental Sciences, Boston College, Chestnut Hill, MA 02467, USA
Yair Rosenthal
Department of Marine and Coastal Science, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
Department of Earth and Planetary Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
Chenyu Zhu
Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
Patrick J. Bartlein
Department of Geography, University of Oregon, Eugene, OR 97403-1251, USA
Jonathan M. Gregory
National Center for Atmospheric Science, University of Reading, Reading, UK
Met Office Hadley Centre, Exeter, UK
Peter Köhler
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany
Zhengyu Liu
Department of Geography, The Ohio State University, Columbus, OH 43210, USA
Daniel P. Schrag
Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA
Related authors
No articles found.
Takashi Obase, Laurie Menviel, Ayako Abe-Ouchi, Tristan Vadsaria, Ruza Ivanovic, Brooke Snoll, Sam Sherriff-Tadano, Paul J. Valdes, Lauren Gregoire, Marie-Luise Kapsch, Uwe Mikolajewicz, Nathaelle Bouttes, Didier Roche, Fanny Lhardy, Chengfei He, Bette Otto-Bliesner, Zhengyu Liu, and Wing-Le Chan
Clim. Past, 21, 1443–1463, https://doi.org/10.5194/cp-21-1443-2025, https://doi.org/10.5194/cp-21-1443-2025, 2025
Short summary
Short summary
This study analyses transient simulations of the last deglaciation performed by six climate models to understand the processes driving high-southern-latitude temperature changes. We find that atmospheric CO2 and AMOC (Atlantic Meridional Overturning Circulation) changes are the primary drivers of the warming and cooling during the middle stage of the deglaciation. The analysis highlights the model's sensitivity of CO2 and AMOC to meltwater and the meltwater history of temperature changes at high southern latitudes.
Peter Köhler
Clim. Past, 21, 1043–1060, https://doi.org/10.5194/cp-21-1043-2025, https://doi.org/10.5194/cp-21-1043-2025, 2025
Short summary
Short summary
Using a carbon cycle model, I show that the 405 kyr periodicity found in marine δ13C during the last 5 million years and the offset in atmospheric δ13CO2 between the Last Glacial Maximum and the Penultimate Glacial Maximum are probably related to each other. They can be explained by variations in the δ13C signature of weathered carbonate rock or of volcanically degassed CO2, which vary mainly with obliquity (41 kyr), suggesting that Northern Hemispheric land ice sheets are their ultimate drivers.
Ying Ye, Guy Munhoven, Peter Köhler, Martin Butzin, Judith Hauck, Özgür Gürses, and Christoph Völker
Geosci. Model Dev., 18, 977–1000, https://doi.org/10.5194/gmd-18-977-2025, https://doi.org/10.5194/gmd-18-977-2025, 2025
Short summary
Short summary
Many biogeochemistry models assume all material reaching the seafloor is remineralized and returned to solution, which is sufficient for studies on short-term climate change. Under long-term climate change, the carbon storage in sediments slows down carbon cycling and influences feedbacks in the atmosphere–ocean–sediment system. This paper describes the coupling of a sediment model to an ocean biogeochemistry model and presents results under the pre-industrial climate and under CO2 perturbation.
Tal Y. Shutkin, Bryan G. Mark, Nathan D. Stansell, Rolando Cruz Encarnación, Henry H. Brecher, Zhengyu Liu, Bidhyananda Yadav, and Forrest S. Schoessow
EGUsphere, https://doi.org/10.5194/egusphere-2024-3194, https://doi.org/10.5194/egusphere-2024-3194, 2025
Short summary
Short summary
Queshque Glacier, a tropical glacier located in central Peru, has lost about 22.5 million cubic meters of water since 2008. Despite a possible increase in recent snowfall, our research shows that ice loss has been caused by steadily warming temperatures. We also see that the formation of a new lake at the base of the glacier has sped up Queshque’s rate of retreat. We find that changes in glacier water storage are increasingly related to conditions in the Pacific Ocean during the austral summer.
Peyton M. Cavnar, Paul R. Bierman, Jeremy D. Shakun, Lee B. Corbett, Danielle LeBlanc, Gillian L. Galford, and Marc Caffee
EGUsphere, https://doi.org/10.5194/egusphere-2024-2233, https://doi.org/10.5194/egusphere-2024-2233, 2024
Short summary
Short summary
To investigate the Laurentide Ice Sheet’s erosivity before and during the Last Glacial Maximum, we sampled sand deposited by ice in eastern Canada before final deglaciation. We also sampled modern river sand. The 26Al and 10Be measured in glacial deposited sediments suggests that ice remained during some Pleistocene warm periods and was an inefficient eroder. Similar concentrations of 26Al and 10Be in modern sand suggests that most modern river sediment is sourced from glacial deposits.
Sam Sherriff-Tadano, Ruza Ivanovic, Lauren Gregoire, Charlotte Lang, Niall Gandy, Jonathan Gregory, Tamsin L. Edwards, Oliver Pollard, and Robin S. Smith
Clim. Past, 20, 1489–1512, https://doi.org/10.5194/cp-20-1489-2024, https://doi.org/10.5194/cp-20-1489-2024, 2024
Short summary
Short summary
Ensemble simulations of the climate and ice sheets of the Last Glacial Maximum (LGM) are performed with a new coupled climate–ice sheet model. Results show a strong sensitivity of the North American ice sheet to the albedo scheme, while the Greenland ice sheet appeared more sensitive to basal sliding schemes. Our result implies a potential connection between the North American ice sheet at the LGM and the future Greenland ice sheet through the albedo scheme.
Lingwei Li, Zhengyu Liu, Jinbo Du, Lingfeng Wan, and Jiuyou Lu
Clim. Past, 20, 1161–1175, https://doi.org/10.5194/cp-20-1161-2024, https://doi.org/10.5194/cp-20-1161-2024, 2024
Short summary
Short summary
Radiocarbon proxies suggest that the deep waters are poorly ventilated during the Last Glacial Maximum (LGM). Here we use two transient simulations with tracers of radiocarbon and ideal age to show that the deep-ocean ventilation age is not much older at the LGM compared to the present day because of the strong glacial Antarctic Bottom Water transport. In contrast, the ventilation age is older during deglaciation mainly due to weakening of Antarctic Bottom Water transport.
Peter Köhler and Stefan Mulitza
Clim. Past, 20, 991–1015, https://doi.org/10.5194/cp-20-991-2024, https://doi.org/10.5194/cp-20-991-2024, 2024
Short summary
Short summary
We constructed 160 kyr long mono-specific stacks of δ13C and of δ18O from the wider tropics from the planktic foraminifera G. ruber and/or T. sacculifer and compared them with carbon cycle simulations using the BICYCLE-SE model. In our stacks and our model-based interpretation, we cannot detect a species-specific isotopic fractionation during hard-shell formation as a function of carbonate chemistry in the surrounding seawater, something which is called a carbonate ion effect.
Martin Butzin, Ying Ye, Christoph Völker, Özgür Gürses, Judith Hauck, and Peter Köhler
Geosci. Model Dev., 17, 1709–1727, https://doi.org/10.5194/gmd-17-1709-2024, https://doi.org/10.5194/gmd-17-1709-2024, 2024
Short summary
Short summary
In this paper we describe the implementation of the carbon isotopes 13C and 14C into the marine biogeochemistry model FESOM2.1-REcoM3 and present results of long-term test simulations. Our model results are largely consistent with marine carbon isotope reconstructions for the pre-anthropogenic period, but also exhibit some discrepancies.
Robert E. Kopp, Gregory G. Garner, Tim H. J. Hermans, Shantenu Jha, Praveen Kumar, Alexander Reedy, Aimée B. A. Slangen, Matteo Turilli, Tamsin L. Edwards, Jonathan M. Gregory, George Koubbe, Anders Levermann, Andre Merzky, Sophie Nowicki, Matthew D. Palmer, and Chris Smith
Geosci. Model Dev., 16, 7461–7489, https://doi.org/10.5194/gmd-16-7461-2023, https://doi.org/10.5194/gmd-16-7461-2023, 2023
Short summary
Short summary
Future sea-level rise projections exhibit multiple forms of uncertainty, all of which must be considered by scientific assessments intended to inform decision-making. The Framework for Assessing Changes To Sea-level (FACTS) is a new software package intended to support assessments of global mean, regional, and extreme sea-level rise. An early version of FACTS supported the development of the IPCC Sixth Assessment Report sea-level projections.
Andrew G. Jones, Shaun A. Marcott, Andrew L. Gorin, Tori M. Kennedy, Jeremy D. Shakun, Brent M. Goehring, Brian Menounos, Douglas H. Clark, Matias Romero, and Marc W. Caffee
The Cryosphere, 17, 5459–5475, https://doi.org/10.5194/tc-17-5459-2023, https://doi.org/10.5194/tc-17-5459-2023, 2023
Short summary
Short summary
Mountain glaciers today are fractions of their sizes 140 years ago, but how do these sizes compare to the past 11,000 years? We find that four glaciers in the United States and Canada have reversed a long-term trend of growth and retreated to positions last occupied thousands of years ago. Notably, each glacier occupies a unique position relative to its long-term history. We hypothesize that unequal modern retreat has caused the glaciers to be out of sync relative to their Holocene histories.
Hélène Seroussi, Vincent Verjans, Sophie Nowicki, Antony J. Payne, Heiko Goelzer, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Torsten Albrecht, Xylar Asay-Davis, Alice Barthel, Reinhard Calov, Richard Cullather, Christophe Dumas, Benjamin K. Galton-Fenzi, Rupert Gladstone, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Tore Hattermann, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Nicolas C. Jourdain, Thomas Kleiner, Eric Larour, Gunter R. Leguy, Daniel P. Lowry, Chistopher M. Little, Mathieu Morlighem, Frank Pattyn, Tyler Pelle, Stephen F. Price, Aurélien Quiquet, Ronja Reese, Nicole-Jeanne Schlegel, Andrew Shepherd, Erika Simon, Robin S. Smith, Fiammetta Straneo, Sainan Sun, Luke D. Trusel, Jonas Van Breedam, Peter Van Katwyk, Roderik S. W. van de Wal, Ricarda Winkelmann, Chen Zhao, Tong Zhang, and Thomas Zwinger
The Cryosphere, 17, 5197–5217, https://doi.org/10.5194/tc-17-5197-2023, https://doi.org/10.5194/tc-17-5197-2023, 2023
Short summary
Short summary
Mass loss from Antarctica is a key contributor to sea level rise over the 21st century, and the associated uncertainty dominates sea level projections. We highlight here the Antarctic glaciers showing the largest changes and quantify the main sources of uncertainty in their future evolution using an ensemble of ice flow models. We show that on top of Pine Island and Thwaites glaciers, Totten and Moscow University glaciers show rapid changes and a strong sensitivity to warmer ocean conditions.
Luke Skinner, Francois Primeau, Aurich Jeltsch-Thömmes, Fortunat Joos, Peter Köhler, and Edouard Bard
Clim. Past, 19, 2177–2202, https://doi.org/10.5194/cp-19-2177-2023, https://doi.org/10.5194/cp-19-2177-2023, 2023
Short summary
Short summary
Radiocarbon is best known as a dating tool, but it also allows us to track CO2 exchange between the ocean and atmosphere. Using decades of data and novel mapping methods, we have charted the ocean’s average radiocarbon ″age” since the last Ice Age. Combined with climate model simulations, these data quantify the ocean’s role in atmospheric CO2 rise since the last Ice Age while also revealing that Earth likely received far more cosmic radiation during the last Ice Age than hitherto believed.
Esmeralda Cruz-Silva, Sandy P. Harrison, I. Colin Prentice, Elena Marinova, Patrick J. Bartlein, Hans Renssen, and Yurui Zhang
Clim. Past, 19, 2093–2108, https://doi.org/10.5194/cp-19-2093-2023, https://doi.org/10.5194/cp-19-2093-2023, 2023
Short summary
Short summary
We examined 71 pollen records (12.3 ka to present) in the eastern Mediterranean, reconstructing climate changes. Over 9000 years, winters gradually warmed due to orbital factors. Summer temperatures peaked at 4.5–5 ka, likely declining because of ice sheets. Moisture increased post-11 kyr, remaining high from 10–6 kyr before a slow decrease. Climate models face challenges in replicating moisture transport.
Claudia Hinrichs, Peter Köhler, Christoph Völker, and Judith Hauck
Biogeosciences, 20, 3717–3735, https://doi.org/10.5194/bg-20-3717-2023, https://doi.org/10.5194/bg-20-3717-2023, 2023
Short summary
Short summary
This study evaluated the alkalinity distribution in 14 climate models and found that most models underestimate alkalinity at the surface and overestimate it in the deeper ocean. It highlights the need for better understanding and quantification of processes driving alkalinity distribution and calcium carbonate dissolution and the importance of accounting for biases in model results when evaluating potential ocean alkalinity enhancement experiments.
Aaron M. Barth, Elizabeth G. Ceperley, Claire Vavrus, Shaun A. Marcott, Jeremy D. Shakun, and Marc W. Caffee
Geochronology, 4, 731–743, https://doi.org/10.5194/gchron-4-731-2022, https://doi.org/10.5194/gchron-4-731-2022, 2022
Short summary
Short summary
Deposits left behind by past glacial activity provide insight into the previous size and behavior of glaciers and act as another line of evidence for past climate. Here we present new age control for glacial deposits in the mountains of Montana and Wyoming, United States. While some deposits indicate glacial activity within the last 2000 years, others are shown to be older than previously thought, thus redefining the extent of regional Holocene glaciation.
Antony Siahaan, Robin S. Smith, Paul R. Holland, Adrian Jenkins, Jonathan M. Gregory, Victoria Lee, Pierre Mathiot, Antony J. Payne, Jeff K. Ridley, and Colin G. Jones
The Cryosphere, 16, 4053–4086, https://doi.org/10.5194/tc-16-4053-2022, https://doi.org/10.5194/tc-16-4053-2022, 2022
Short summary
Short summary
The UK Earth System Model is the first to fully include interactions of the atmosphere and ocean with the Antarctic Ice Sheet. Under the low-greenhouse-gas SSP1–1.9 (Shared Socioeconomic Pathway) scenario, the ice sheet remains stable over the 21st century. Under the strong-greenhouse-gas SSP5–8.5 scenario, the model predicts strong increases in melting of large ice shelves and snow accumulation on the surface. The dominance of accumulation leads to a sea level fall at the end of the century.
Robin S. Smith, Steve George, and Jonathan M. Gregory
Geosci. Model Dev., 14, 5769–5787, https://doi.org/10.5194/gmd-14-5769-2021, https://doi.org/10.5194/gmd-14-5769-2021, 2021
Short summary
Short summary
Many of the complex computer models used to study the physics of the natural world treat ice sheets as fixed and unchanging, capable of only simple interactions with the rest of the climate. This is partly because it is technically very difficult to usefully do anything more realistic. We have adapted a climate model so it can be joined together with a dynamical model of the Greenland ice sheet. This gives us a powerful tool to help us better understand how ice sheets and the climate interact.
Jonathan M. Gregory, Steven E. George, and Robin S. Smith
The Cryosphere, 14, 4299–4322, https://doi.org/10.5194/tc-14-4299-2020, https://doi.org/10.5194/tc-14-4299-2020, 2020
Short summary
Short summary
Melting of the Greenland ice sheet as a consequence of global warming could raise global-mean sea level by up to 7 m. We have studied this using a newly developed computer model. With recent climate maintained, sea level would rise by 0.5–2.5 m over many millennia due to Greenland ice loss: the warmer the climate, the greater the sea level rise. Beyond about 3.5 m it would become partially irreversible. In order to avoid this outcome, anthropogenic climate change must be reversed soon enough.
Chris M. Brierley, Anni Zhao, Sandy P. Harrison, Pascale Braconnot, Charles J. R. Williams, David J. R. Thornalley, Xiaoxu Shi, Jean-Yves Peterschmitt, Rumi Ohgaito, Darrell S. Kaufman, Masa Kageyama, Julia C. Hargreaves, Michael P. Erb, Julien Emile-Geay, Roberta D'Agostino, Deepak Chandan, Matthieu Carré, Partrick J. Bartlein, Weipeng Zheng, Zhongshi Zhang, Qiong Zhang, Hu Yang, Evgeny M. Volodin, Robert A. Tomas, Cody Routson, W. Richard Peltier, Bette Otto-Bliesner, Polina A. Morozova, Nicholas P. McKay, Gerrit Lohmann, Allegra N. Legrande, Chuncheng Guo, Jian Cao, Esther Brady, James D. Annan, and Ayako Abe-Ouchi
Clim. Past, 16, 1847–1872, https://doi.org/10.5194/cp-16-1847-2020, https://doi.org/10.5194/cp-16-1847-2020, 2020
Short summary
Short summary
This paper provides an initial exploration and comparison to climate reconstructions of the new climate model simulations of the mid-Holocene (6000 years ago). These use state-of-the-art models developed for CMIP6 and apply the same experimental set-up. The models capture several key aspects of the climate, but some persistent issues remain.
Heiko Goelzer, Sophie Nowicki, Anthony Payne, Eric Larour, Helene Seroussi, William H. Lipscomb, Jonathan Gregory, Ayako Abe-Ouchi, Andrew Shepherd, Erika Simon, Cécile Agosta, Patrick Alexander, Andy Aschwanden, Alice Barthel, Reinhard Calov, Christopher Chambers, Youngmin Choi, Joshua Cuzzone, Christophe Dumas, Tamsin Edwards, Denis Felikson, Xavier Fettweis, Nicholas R. Golledge, Ralf Greve, Angelika Humbert, Philippe Huybrechts, Sebastien Le clec'h, Victoria Lee, Gunter Leguy, Chris Little, Daniel P. Lowry, Mathieu Morlighem, Isabel Nias, Aurelien Quiquet, Martin Rückamp, Nicole-Jeanne Schlegel, Donald A. Slater, Robin S. Smith, Fiamma Straneo, Lev Tarasov, Roderik van de Wal, and Michiel van den Broeke
The Cryosphere, 14, 3071–3096, https://doi.org/10.5194/tc-14-3071-2020, https://doi.org/10.5194/tc-14-3071-2020, 2020
Short summary
Short summary
In this paper we use a large ensemble of Greenland ice sheet models forced by six different global climate models to project ice sheet changes and sea-level rise contributions over the 21st century.
The results for two different greenhouse gas concentration scenarios indicate that the Greenland ice sheet will continue to lose mass until 2100, with contributions to sea-level rise of 90 ± 50 mm and 32 ± 17 mm for the high (RCP8.5) and low (RCP2.6) scenario, respectively.
Hélène Seroussi, Sophie Nowicki, Antony J. Payne, Heiko Goelzer, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Torsten Albrecht, Xylar Asay-Davis, Alice Barthel, Reinhard Calov, Richard Cullather, Christophe Dumas, Benjamin K. Galton-Fenzi, Rupert Gladstone, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Tore Hattermann, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Nicolas C. Jourdain, Thomas Kleiner, Eric Larour, Gunter R. Leguy, Daniel P. Lowry, Chistopher M. Little, Mathieu Morlighem, Frank Pattyn, Tyler Pelle, Stephen F. Price, Aurélien Quiquet, Ronja Reese, Nicole-Jeanne Schlegel, Andrew Shepherd, Erika Simon, Robin S. Smith, Fiammetta Straneo, Sainan Sun, Luke D. Trusel, Jonas Van Breedam, Roderik S. W. van de Wal, Ricarda Winkelmann, Chen Zhao, Tong Zhang, and Thomas Zwinger
The Cryosphere, 14, 3033–3070, https://doi.org/10.5194/tc-14-3033-2020, https://doi.org/10.5194/tc-14-3033-2020, 2020
Short summary
Short summary
The Antarctic ice sheet has been losing mass over at least the past 3 decades in response to changes in atmospheric and oceanic conditions. This study presents an ensemble of model simulations of the Antarctic evolution over the 2015–2100 period based on various ice sheet models, climate forcings and emission scenarios. Results suggest that the West Antarctic ice sheet will continue losing a large amount of ice, while the East Antarctic ice sheet could experience increased snow accumulation.
Cited articles
Ahn, S., Khider, D., Lisiecki, L. E., and Lawrence, C. E.: A probabilistic Pliocene–Pleistocene stack of benthic δ18O using a profile hidden Markov model, Dynamics and Statistics of the Climate System, 2, 1–16, 2017.
Alder, J. R. and Hostetler, S. W.: Global climate simulations at 3000-year intervals for the last 21 000 years with the GENMOM coupled atmosphere–ocean model, Clim. Past, 11, 449–471, https://doi.org/10.5194/cp-11-449-2015, 2015.
Baggenstos, D., Haberli, M., Schmitt, J., Shackleton, S. A., Birner, B., Severinghaus, J. P., Kellerhals, T., and Fischer, H.: Earth's radiative imbalance from the Last Glacial Maximum to the present, P. Natl. Acad. Sci. USA, 116, 14881–14886, https://doi.org/10.1073/pnas.1905447116, 2019.
Barrientos, N., Lear, C. H., Jakobsson, M., Stranne, C., O'Regan, M., Cronin, T. M., Gukov, A. Y., and Coxall, H. K.: Arctic Ocean benthic foraminifera Mg Ca ratios and global Mg Ca-temperature calibrations: New constraints at low temperatures, Geochim. Cosmochim. Ac., 236, 240–259, https://doi.org/10.1016/j.gca.2018.02.036, 2018.
Bartlein, P.: pjbartlein/MOTvsSST: MOT vs SST regressions (v0.1), Zenodo [code], https://doi.org/10.5281/zenodo.14759006, 2025.
Bates, S. L., Siddall, M., and Waelbroeck, C.: Hydrographic variations in deep ocean temperature over the mid-Pleistocene transition, Quaternary Sci. Rev., 88, 147–158, https://doi.org/10.1016/j.quascirev.2014.01.020, 2014.
Bereiter, B., Shackleton, S., Baggenstos, D., Kawamura, K., and Severinghaus, J.: Mean global ocean temperatures during the last glacial transition, Nature, 553, 39–44, https://doi.org/10.1038/nature25152, 2018.
Bijma, J., Spero, H. J., and Lea, D. W.: Reassessing foraminiferal stable isotope geochemistry: Impact of the oceanic carbonate system (experimental results), in: Use of Proxies in Paleoceanography: Examples from the South Atlantic, edited by: Fischer, G. and Wefer, G., Springer-Verlag, Berlin, 489–512, https://doi.org/10.1007/978-3-642-58646-0_20, 1999.
Braconnot, P., Harrison, S. P., Kageyama, M., Bartlein, P. J., Masson-Delmotte, V., Abe-Ouchi, A., Otto-Bliesner, B., and Zhao, Y.: Evaluation of climate models using palaeoclimatic data, Nat. Clim. Change, 2, 417–424, https://doi.org/10.1038/nclimate1456, 2012.
Bronselaer, B. and Zanna, L.: Heat and carbon coupling reveals ocean warming due to circulation changes, Nature, 584, 227–233, https://doi.org/10.1038/s41586-020-2573-5, 2020.
Cheng, L. J., von Schuckmann, K., Abraham, J. P., Trenberth, K. E., Mann, M. E., Zanna, L., England, M. H., Zika, J. D., Fasullo, J. T., Yu, Y. Q., Pan, Y. Y., Zhu, J., News, E. R., Bronselaer, B., and Lin, X. P.: Past and future ocean warming, Nature Reviews Earth & Environment, 3, 776–794, https://doi.org/10.1038/s43017-022-00345-1, 2022.
Church, J. A., Clark, P. U., Cazenave, A., Gregory, J. M., Jevrejeva, S., Levermann, A., Merrifield, M. A., Milne, G. A., Nerem, R. S., Nunn, P. D., Payne, A. J., Pfeffer, W. T., Stammer, D., and Unnikrishnan, A. S.: Sea Level Change, in: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1137–1216, https://doi.org/10.1017/9781009157896.011, 2013.
Clark, P. U., Shakun, J. D., Marcott, S. A., Mix, A. C., Eby, M., Kulp, S., Levermann, A., Milne, G. A., Pfister, P. L., Santer, B. D., Schrag, D. P., Solomon, S., Stocker, T. F., Strauss, B. H., Weaver, A. J., Winkelmann, R., Archer, D., Bard, E., Goldner, A., Lambeck, K., Pierrehumbert, R. T., and Plattner, G. K.: Consequences of twenty-first-century policy for multi-millennial climate and sea-level change, Nat. Clim. Change, 6, 360–369, https://doi.org/10.1038/nclimate2923, 2016.
Clark, P. U., Shakun, J. D., Rosenthal, Y., Köhler, P., and Bartlein, P. J.: Global and regional temperature change over the last 4.5 million years, Science, 383, 884–890, 2024.
Cleveland, W. S., Grosse, E., and Shyu, W. M.: Local regression models, in: Statistical Models in S, edited by: Chambers, J. M. and Hastie, T. J., Chapman and Hall, https://doi.org/10.1201/9780203738535, 1992.
Cramer, B. S., Miller, K. G., Barrett, P. J., and Wright, J. D.: Late Cretaceous-Neogene trends in deep ocean temperature and continental ice volume: Reconciling records of benthic foraminiferal geochemistry (delta O-18 and Mg Ca) with sea level history, J. Geophys. Res.-Oceans, 116, C12023, https://doi.org/10.1029/2011jc007255, 2011.
de Boer, B., Lourens, L. J., and van de Wal, R. S. W.: Persistent 400,000-year variability of Antarctic ice volume and the carbon cycle is revealed throughout the Plio-Pleistocene, Nat. Commun., 5, 2999, https://doi.org/10.1038/ncomms3999, 2014.
Dumitru, O. A., Austermann, J., Polyak, V. J., Fornos, J. J., Asmerom, Y., Gines, J., Gines, A., and Onac, B. P.: Constraints on global mean sea level during Pliocene warmth, Nature, 574, 233–236, https://doi.org/10.1038/s41586-019-1543-2, 2019.
Dumitru, O. A., Austermann, J., Polyak, V. J., Fornos, J. J., Asmerom, Y., Gines, J., Gines, A., and Onac, B. P.: Sea-level stands from the Western Mediterranean over the past 6.5 million years, Sci. Rep.-UK, 11, 6681, https://doi.org/10.1038/s41598-020-80025-6, 2021.
Dwyer, G. S. and Chandler, M. A.: Mid-Pliocene sea level and continental ice volume based on coupled benthic Mg Ca palaeotemperatures and oxygen isotopes, Philos. T. Roy. Soc. A, 367, 157–168, https://doi.org/10.1098/rsta.2008.0222, 2009.
Elderfield, H., Ferretti, P., Greaves, M., Crowhurst, S., McCave, I. N., Hodell, D., and Piotrowski, A. M.: Evolution of ocean temperature and ice volume through the mid-Pleistocene climate transition, Science, 337, 704–709, https://doi.org/10.1126/science.1221294, 2012.
Emiliani, C.: Temperatures of Pacific bottom waters and polar superficial waters during the Tertiary, Science, 119, 853–855, 1954.
Evans, D., Brugger, J., Inglis, G. N., and Valdes, P.: The temperature of the deep ocean Is a robust proxy for global mean surface temperature during the Cenozoic, Paleoceanography and Paleoclimatology, 39, e2023PA004788, https://doi.org/10.1029/2023PA004788, 2024.
Farmer, J. R., Honisch, B., Haynes, L. L., Kroon, D., Jung, S., Ford, H. L., Raymo, M. E., Jaume-Segui, M., Bell, D. B., Goldstein, S. L., Pena, L. D., Yehudai, M., and Kim, J.: Deep Atlantic Ocean carbon storage and the rise of 100,000-year glacial cycles, Nat. Geosci., 12, 355–360, https://doi.org/10.1038/s41561-019-0334-6, 2019.
Ford, H. L. and Raymo, M. E.: Regional and global signals in seawater δ18O records across the mid-Pleistocene transition, Geology, 48, 113–117, https://doi.org/10.1130/g46546.1, 2020.
Fox-Kemper, B., Hewitt, H., Xiao, C., Aðalgeirsdóttir, G., Drijfhout, S. S., Edwards, T. L., Golledge, N. R., Hemer, M., Kopp, R. E., Krinner, G., Mix, A., Notz, D., Nowicki, S., Nurhati, I. S., Ruiz, L., Sallée, J.-B., Slangen, A. B. A., and Yu, Y.: Ocean, Cryosphere, and Sea Level Change, in: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S. L., Péan, C., Berger, S., Caud, N., Chen, L., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., Cambriidge University Press, Cambridge, UK, 1211–1362, https://doi.org/10.1017/9781009157896.011, 2021.
Galbraith, E. and de Lavergne, C.: Response of a comprehensive climate model to a broad range of external forcings: relevance for deep ocean ventilation and the development of late Cenozoic ice ages, Clim. Dynam., 52, 653–679, https://doi.org/10.1007/s00382-018-4157-8, 2019.
Gasson, E., DeConto, R. M., and Pollard, D.: Modeling the oxygen isotope composition of the Antarctic ice sheet and its significance to Pliocene sea level, Geology, 44, 827–830, https://doi.org/10.1130/g38104.1, 2016.
Goudsmit-Harzevoort, B., Lansu, A., Baatsen, M. L. J., von der Heydt, A. S., de Winter, N. J., Zhang, Y. R., Abe-Ouchi, A., de Boer, A., Chan, W. L., Donnadieu, Y., Hutchinson, D. K., Knorr, G., Ladant, J. B., Morozova, P., Niezgodzki, I., Steinig, S., Tripati, A., Zhang, Z. S., Zhu, J., and Ziegler, M.: The Relationship Between the Global Mean Deep-Sea and Surface Temperature During the Early Eocene, Paleoceanography and Paleoclimatology, 38, e2022PA004532, https://doi.org/10.1029/2022pa004532, 2023.
Gray, W. R., de Lavergne, C., Wills, R. J. C., Menviel, L., Spence, P., Holzer, M., Kageyama, M., and Michel, E.: Poleward Shift in the Southern Hemisphere Westerly Winds Synchronous With the Deglacial Rise in CO2, Paleoceanography and Paleoclimatology, 38, e2023PA004666, https://doi.org/10.1029/2023pa004666, 2023.
Gregory, J. M.: Vertical heat transports in the ocean and their effect on time-dependent climate change, Clim. Dynam., 16, 501–515, 2000.
Gregory, J. M., Stouffer, R. J., Raper, S. C. B., Stott, P. A., and Rayner, N. A.: An observationally based estimate of the climate sensitivity, J. Climate, 15, 3117–3121, https://doi.org/10.1175/1520-0442(2002)015<3117:Aobeot>2.0.Co;2, 2002.
Gregory, J. M., Bouttes, N., Griffies, S. M., Haak, H., Hurlin, W. J., Jungclaus, J., Kelley, M., Lee, W. G., Marshall, J., Romanou, A., Saenko, O. A., Stammer, D., and Winton, M.: The Flux-Anomaly-Forced Model Intercomparison Project (FAFMIP) contribution to CMIP6: investigation of sea-level and ocean climate change in response to CO2 forcing, Geosci. Model Dev., 9, 3993–4017, https://doi.org/10.5194/gmd-9-3993-2016, 2016.
Gregory, J. M., Bloch-Johnson, J., Couldrey, M. P., Exarchou, E., Griffies, S. M., Kuhlbrodt, T., Newsom, E., Saenko, O. A., Suzuki, T., Wu, Q. R., Urakawa, S., and Zanna, L.: A new conceptual model of global ocean heat uptake, Clim. Dynam., 62, 1669–1713, https://doi.org/10.1007/s00382-023-06989-z, 2024.
Gu, S., Liu, Z., Oppo, D. W., Lynch-Stieglitz, J., Jahn, A., Zhang, J., and Wu, L.: Assessing the potential capability of reconstructing glacial Atlantic water masses and AMOC using multiple proxies in CESM, Earth Planet. Sc. Lett., 541, 116294, https://doi.org/10.1016/j.epsl.2020.116294, 2020.
Haeberli, M., Baggenstos, D., Schmitt, J., Grimmer, M., Michel, A., Kellerhals, T., and Fischer, H.: Snapshots of mean ocean temperature over the last 700 000 years using noble gases in the EPICA Dome C ice core, Clim. Past, 17, 843–867, https://doi.org/10.5194/cp-17-843-2021, 2021.
Hansen, J., Sato, M., Russell, G., and Kharecha, P.: Climate sensitivity, sea level and atmospheric carbon dioxide, Philos. T. Roy. Soc. A, 371, 20120294, https://doi.org/10.1098/rsta.2012.0294, 2013.
Hansen, J. E., Sato, M., Simons, L., Nazarenko, L. S., Sangha, I., Kharecha, P., Zachos, J. C., von Schuckmann, K., Loeb, N. G., Osman, M. B., Jin, Q., Tselioudis, G., Jeong, E., Lacis, A., Ruedy, R., Russell, G., Cao, J., and Li, J.: Global warming in the pipeline, Oxford Open Climate Change, 3, kgad008, https://doi.org/10.1093/oxfclm/kgad008, 2023.
Hastie, T. J.: Generalized additive models, in: Statistical Models in S, edited by: Chambers, J. M., and Hastie, T. J., Chapman and Hall, https://doi.org/10.1201/9780203738535, 1992.
Haywood, A. M., Tindall, J. C., Dowsett, H. J., Dolan, A. M., Foley, K. M., Hunter, S. J., Hill, D. J., Chan, W.-L., Abe-Ouchi, A., Stepanek, C., Lohmann, G., Chandan, D., Peltier, W. R., Tan, N., Contoux, C., Ramstein, G., Li, X., Zhang, Z., Guo, C., Nisancioglu, K. H., Zhang, Q., Li, Q., Kamae, Y., Chandler, M. A., Sohl, L. E., Otto-Bliesner, B. L., Feng, R., Brady, E. C., von der Heydt, A. S., Baatsen, M. L. J., and Lunt, D. J.: The Pliocene Model Intercomparison Project Phase 2: large-scale climate features and climate sensitivity, Clim. Past, 16, 2095–2123, https://doi.org/10.5194/cp-16-2095-2020, 2020.
He, C., Liu, Z., Otto-Bliesner, B. L., Brady, E. C., Zhu, C., Tomas, R., Clark, P. U., Zhu, J., Jahn, A., Gu, S., Zhang, J., Nusbaumer, J., Noone, D., Cheng, H., Wang, Y., Yan, M., and Bao, Y.: Hydroclimate footprint of pan-Asian monsoon water isotope during the last deglaciation, Science Advances, 7, eabe2611, https://doi.org/10.1126/sciadv.abe2611, 2021.
He, F.: Simulating transient climate evolution of the last deglaciation with CCSM3, The University of Wisconsin – Madison, https://www.researchgate.net/profile/Feng-He-27/publication/263618839_Simulating_transient_climate_ evolution_of_the_last_deglaciation_with_CCSM3/links/ 0c96053b5fc619188f000000/Simulating-transient-climate-evolution-of-the-last-deglaciation-with-CCSM3.pdf (last access: 1 January 2025), 2011.
Heuzé, C., Heywood, K. J., Stevens, D. P., and Ridley, J. K.: Changes in global ocean bottom properties and volume transports in CMIP5 models under climate change scenarios, J. Climate, 28, 2917–2944, 2015.
Hodell, D. A. and Venz-Curtis, K. A.: Late Neogene history of deepwater ventilation in the Southern Ocean, Geochem. Geophy. Geosy., 7, Q09001, https://doi.org/10.1029/2005gc001211, 2006.
Jakob, K. A., Wilson, P. A., Pross, J., Ezard, T. H. G., Fiebig, J., Repschlager, J., and Friedrich, O.: A new sea-level record for the Neogene/Quaternary boundary reveals transition to a more stable East Antarctic Ice Sheet, P. Natl. Acad. Sci. USA, 117, 30980–30987, https://doi.org/10.1073/pnas.2004209117, 2020.
Johnson, G. C.: Quantifying Antarctic Bottom Water and North Atlantic Deep Water volumes, J. Geophys. Res., 113, C05027, https://doi.org/10.1029/2007JC004477, 2008.
Johnson, G. C., Sadman Mahmud, A. K. M., Macdonald, A. M., and Twining, B. S.: Antarctic Bottom Water warming, freshening, and contraction in the eastern Bellingshausen Basin, Geophys. Res. Lett., 51, e2024GL109937, https://doi.org/10.1029/2024GL109937, 2024.
Khatiwala, S., Primeau, F., and Holzer, M.: Ventilation of the deep ocean constrained with tracer observations and implications for radiocarbon estimates of ideal mean age, Earth Planet. Sc. Lett., 325–326, 116–125, 2012.
Kim, S. T. and O'Neil, J. R.: Equilibrium and nonequilibrium oxygen isotope effects in synthetic carbonates, Geochim. Cosmochim. Ac., 61, 3461–3475, https://doi.org/10.1016/s0016-7037(97)00169-5, 1997.
Köhler, P.: Atmospheric CO2 concentration based on boron isotopes versus simulations of the global carbon cycle during the Plio-Pleistocene, Paleoceanography and Paleoclimatology, 38, e2022PA004439, https://doi.org/10.1029/2022PA004439, 2023.
Köhler, P. and Bintanja, R.: The carbon cycle during the Mid Pleistocene Transition: the Southern Ocean Decoupling Hypothesis, Clim. Past, 4, 311–332, https://doi.org/10.5194/cp-4-311-2008, 2008.
Köhler, P. and Mulitza, S.: No detectable influence of the carbonate ion effect on changes in stable carbon isotope ratios (δ13C) of shallow dwelling planktic foraminifera over the past 160 kyr, Clim. Past, 20, 991–1015, https://doi.org/10.5194/cp-20-991-2024, 2024.
Kuhlbrodt, T. and Gregory, J. M.: Ocean heat uptake and its consequences for the magnitude of sea level rise and climate change, Geophys. Res. Lett., 39, L18608, https://doi.org/10.1029/2012gl052952, 2012.
Lambeck, K., Rouby, H., Purcell, A., Sun, Y., and Sambridge, M.: Sea level and global ice volumes from the Last Glacial Maximum to the Holocene, P. Natl. Acad. Sci. USA, 111, 15296–15303, 2014.
Lang, D. C., Bailey, I., Wilson, P. A., Chalk, T. B., Foster, G. L., and Gutjahr, M.: Incursions of southern-sourced water into the deep North Atlantic during late Pliocene glacial intensification, Nat. Geosci., 9, 375–379, https://doi.org/10.1038/ngeo2688, 2016.
Lear, C. H., Rosenthal, Y., and Wright, J. D.: The closing of a seaway: ocean water masses and global climate change, Earth Planet. Sc. Lett., 210, 425–436, https://doi.org/10.1016/s0012-821x(03)00164-x, 2003.
Lear, C. H., Billups, K., Rickaby, R. E. M., Diester-Haass, L., Mawbey, E. M., and Sosdian, S. M.: Breathing more deeply: Deep ocean carbon storage during the mid-Pleistocene climate transition, Geology, 44, 1035–1038, https://doi.org/10.1130/g38636.1, 2016.
Li, C., von Storch, J.-S., and Marotzke, J.: Deep-ocean heat uptake and equilibrium climate response, Clim. Dynam., 40, 1071–1086, 2013.
Li, Q., England, M. H., Hogg, A. M., Rintoul, S. R., and Morrison, A. K.: Abyssal ocean overturning slowdown and warming driven by Antarctic meltwater, Nature, 615, 841–847, 2023.
Lisiecki, L. E.: Atlantic overturning responses to obliquity and precession over the last 3 Myr, Paleoceanography, 29, 71–86, https://doi.org/10.1002/2013pa002505, 2014.
Lisiecki, L. E. and Raymo, M. E.: A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records, Paleoceanography, 20, 2004PA001071, https://doi.org/10.1029/2004PA001071, 2005.
Marchitto, T. M., Curry, W. B., Lynch-Stieglitz, J., Bryan, S. P., Cobb, K. M., and Lund, D. C.: Improved oxygen isotope temperature calibrations for cosmopolitan benthic foraminifera, Geochim. Cosmochim. Ac., 130, 1–11, 2014.
Martin, P. A., Lea, D. W., Rosenthal, Y., Papenfuss, T. P., and Sarnthein, M.: Late Quaternary Deep-Sea Temperatures Inferred From Benthic Foraminiferal Magnesium, Earth Planet. Sc. Lett., 198, 193–209, 2002.
Meckler, A. N., Sexton, P. F., Piasecki, A. M., Leutert, T. J., Marquardt, J., Ziegler, M., Agterhuis, T., Lourens, L. J., Rae, J. W. B., Barnet, J., Tripati, A., and Bernasconi, S. M.: Cenozoic evolution of deep ocean temperature from clumped isotope thermometry, Science, 377, 86–90, https://doi.org/10.1126/science.abk0604, 2022.
Miller, K. G., Wright, J. D., Browning, J. V., Kulpecz, A., Kominz, M., Naish, T. R., Cramer, B. S., Rosenthal, Y., Peltier, W. R., and Sosdian, S.: High tide of the warm Pliocene: Implications of global sea level for Antarctic deglaciation, Geology, 40, 407–410, https://doi.org/10.1130/g32869.1, 2012.
Miller, K. G., Browning, J. V., Schmelz, W. J., Kopp, R. E., Mountain, G. S., and Wright, J. D.: Cenozoic sea-level and cryospheric evolution from deep-sea geochemical and continental margin records, Science Advances, 6, eaaz1346, https://doi.org/10.1126/sciadv.aaz1346, 2020.
Muggeo, V. M. R.: Estimating regression models with unknown break-points, Stat. Med., 22, 3055–3071, 2003.
Nederbragt, A. J.: The effect of seawater carbonate chemistry on the stable isotope composition of Cibicidoides wuellerstorfi and other Cibicidoides species, Paleoceanography and Paleoclimatology, 38, e2023PA004667, https://doi.org/10.1029/2023PA004667, 2023.
Newsom, E., Zanna, L., and Gregory, J.: Background pycnocline depth constrains future ocean heat uptake ffficiency, Geophys. Res. Lett., 50, e2023GL105673, https://doi.org/10.1029/2023gl105673, 2023.
Pena, L. D. and Goldstein, S. L.: Thermohaline circulation crisis and impacts during the mid-Pleistocene transition, Science, 345, 318–322, https://doi.org/10.1126/science.1249770, 2014.
Pöppelmeier, F., Baggenstos, D., Grimmer, M., Liu, Z. J., Schmitt, J., Fischer, H., and Stocker, T. F.: The Effect of Past Saturation Changes on Noble Gas Reconstructions of Mean Ocean Temperature, Geophys. Res. Lett., 50, e2022GL102055, https://doi.org/10.1029/2022gl102055, 2023.
Purkey, S. G., Johnson, G. C., Talley, L. D., Sloyan, B. M., Wijffels, S. E., Smethie, W., Mecking, S., and Katsumata, K.: Unabated bottom water warming and freshening in the South Pacific Ocean, J. Geophys. Res.-Oceans, 124, 1778–1794, 2019.
R: A Language and Environment for Statistical Computing, The R Foundation, https://www.R-project.org/ (last access: 5 January 2025), 2024.
Raymo, M. E., Kozdon, R., Evans, D., Lisiecki, L., and Ford, H. L.: The accuracy of mid-Pliocene δ18O-based ice volume and sea level reconstructions, Earth-Sci. Rev., 177, 291–302, https://doi.org/10.1016/j.earscirev.2017.11.022, 2018.
Rohling, E. J., Yu, J. M., Heslop, D., Foster, G. L., Opdyke, B., and Roberts, A. P.: Sea level and deep-sea temperature reconstructions suggest quasi-stable states and critical transitions over the past 40 million years, Science Advances, 7, eabf5326, https://doi.org/10.1126/sciadv.abf5326, 2021.
Rohling, E. J., Foster, G. L., Gernon, T. M., Grant, K. M., Heslop, D., Hibbert, F. D., Roberts, A. P., and Yu, J.: Comparison and synthesis of sea-level and deep-sea temperature variations over the past 40 million years, Rev. Geophys., 60, e2022RG000775, https://doi.org/10.1029/2022RG000775, 2022.
Rohling, E. J., Gernon, T. M., Heslop, D., Reichart, G. J., Roberts, A. P., and Yu, J.: Reconciling the Apparent Discrepancy Between Cenozoic Deep-Sea Temperatures From Proxies and From Benthic Oxygen Isotope Deconvolution, Paleoceanography and Paleoclimatology, 39, e2024PA004872, https://doi.org/10.1029/2024pa004872, 2024.
Rosenthal, Y., Bova, S., and Zhou, X. L.: A user guide for choosing planktic foraminiferal Mg Ca-temperature calibrations, Paleoceanography and Paleoclimatology, 37, e2022PA004413, https://doi.org/10.1029/2022pa004413, 2022.
Rugenstein, M., Bloch-Johnson, J., Abe-Ouchi, A., Andrews, T., Beyerle, U., Cao, L., Chadha, T., Danabasoglu, G., Dufresne, J. L., Duan, L., Foujols, M. A., Frolicher, T., Geoffroy, O., Gregory, J., Knutti, R., Li, C., Marzocchi, A., Mauritsen, T., Menary, M., Moyer, E., Nazarenko, L., Paynter, D., Saint-Martin, D., Schmidt, G. A., Yamamoto, A., and Yang, S. T.: LongRunMIP: Motivation and Design for a Large Collection of Millennial-Length AOGCM Simulations, B. Am. Meteorol. Soc., 100, 2551–2570, https://doi.org/10.1175/bams-d-19-0068.1, 2019.
Rugenstein, M. A. A., Sedlácek, J., and Knutti, R.: Nonlinearities in patterns of long-term ocean warming, Geophys. Res. Lett., 43, 3380–3388, https://doi.org/10.1002/2016gl068041, 2016.
Saenko, O., Gregory, J. M., Griffies, S. M., Couldrey, M. P., and Dias, F. B.: Contribution of ocean physics and dynamics at different scales to heat uptaken in low-resolution AOGCMs, J. Climate, 34, 2017–2035, 2021.
Schrag, D. P.: Effects of diagenesis on the isotopic record of late Paleogene tropical sea surface temperatures, Chem. Geol., 161, 215–224, https://doi.org/10.1016/s0009-2541(99)00088-1, 1999.
Schrag, D. P., Hampt, G., and Murray, D. W.: Pore fluid constraints on the temperature and oxygen isotopic composition of the glacial ocean, Science, 272, 1930–1932, 1996.
Schrag, D. P., Adkins, J. F., McIntyre, K., Alexander, J. L., Hodell, D. A., Charles, C. D., and McManus, J. F.: The oxygen isotopic composition of seawater during the Last Glacial Maximum, Quaternary Sci. Rev., 21, 331–342, 2002.
Seltzer, A. M., Davidson, P. W., Shackleton, S. A., Nicholson, D. P., and Khatiwala, S.: Global ocean cooling of 2.3 °C during the Last Glacial Maximum, Geophys. Res. Lett., 51, e2024GL108866, https://doi.org/10.1029/2024GL108866, 2024.
Shackleton, S., Bereiter, B., Baggenstos, D., Bauska, T. K., Brook, E. J., Marcott, S. A., and Severinghaus, J. P.: Is the noble gas-based rate of ocean warming during the Younger Dryas overestimated?, Geophys. Res. Lett., 46, 5928–5936, https://doi.org/10.1029/2019gl082971, 2019.
Shackleton, S., Baggenstos, D., Menking, J. A., Dyonisius, M. N., Bereiter, B., Bauska, T. K., Rhodes, R. H., Brook, E. J., Petrenko, V. V., McConnell, J. R., Kellerhals, T., Haberli, M., Schmitt, J., Fischer, H., and Severinghaus, J. P.: Global ocean heat content in the Last Interglacial, Nat. Geosci., 13, 77–81, https://doi.org/10.1038/s41561-019-0498-0, 2020.
Shackleton, S., Menking, J. A., Brook, E., Buizert, C., Dyonisius, M. N., Petrenko, V. V., Baggenstos, D., and Severinghaus, J. P.: Evolution of mean ocean temperature in Marine Isotope Stage 4, Clim. Past, 17, 2273–2289, https://doi.org/10.5194/cp-17-2273-2021, 2021.
Shackleton, S., Seltzer, A., Baggenstos, D., and Lisiecki, L.: Benthic δ18O records Earth's energy imbalance, Nat. Geosci., 16, 797–802, 2023.
Shakun, J. D., Clark, P. U., He, F., Marcott, S. A., Mix, A. C., Liu, Z. Y., Otto-Bliesner, B., Schmittner, A., and Bard, E.: Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation, Nature, 484, 49–55, 2012.
Shakun, J. D., Lea, D. W., Lisiecki, L. E., and Raymo, M. E.: An 800 kyr record of global surface ocean delta O-18 and implications for ice volume-temperature coupling, Earth Planet. Sc. Lett., 426, 58–68, https://doi.org/10.1016/j.epsl.2015.05.042, 2015.
Siddall, M., Honisch, B., Waelbroeck, C., and Huybers, P.: Changes in deep Pacific temperature during the mid-Pleistocene transition and Quaternary, Quaternary Sci. Rev., 29, 170–181, https://doi.org/10.1016/j.quascirev.2009.05.011, 2010.
Sosdian, S. and Rosenthal, Y.: Deep-sea temperature and ice volume changes across the Pliocene-Pleistocene climate transitions, Science, 325, 306–310, https://doi.org/10.1126/science.1169938, 2009.
Sosdian, S. M., Rosenthal, Y., and Toggweiler, J. R.: Deep Atlantic carbonate ion and CaCO3 compensation during the Ice Ages, Paleoceanography and Paleoclimatology, 33, 546–562, https://doi.org/10.1029/2017pa003312, 2018.
Spero, H. J., Bijma, J., Lea, D. W., and Bemis, B. E.: Effect of seawater carbonate concentration on foraminiferal carbon and oxygen isotopes, Nature, 390, 497–500, 1997.
Spratt, R. M. and Lisiecki, L. E.: A Late Pleistocene sea level stack, Clim. Past, 12, 1079–1092, https://doi.org/10.5194/cp-12-1079-2016, 2016.
Tierney, J. E., Zhu, J., King, J., Malevich, S. B., Hakim, G. J., and Poulsen, C. J.: Glacial cooling and climate sensitivity revisited, Nature, 584, 569–573, https://doi.org/10.1038/s41586-020-2617-x, 2020.
Uemura, R., Motoyama, H., Masson-Delmotte, V., Jouzel, J., Kawamura, K., Goto-Azuma, K., Fujita, S., Kuramoto, T., Hirabayashi, M., Miyake, T., Ohno, H., Fujita, K., Abe-Ouchi, A., Iizuka, Y., Horikawa, S., Igarashi, M., Suzuki, K., Suzuki, T., and Fujii, Y.: Asynchrony between Antarctic temperature and CO2 associated with obliquity over the past 720,000 years, Nat. Commun., 9, 961, https://doi.org/10.1038/s41467-018-03328-3, 2018.
von Schuckmann, K., Minière, A., Gues, F., Cuesta-Valero, F. J., Kirchengast, G., Adusumilli, S., Straneo, F., Ablain, M., Allan, R. P., Barker, P. M., Beltrami, H., Blazquez, A., Boyer, T., Cheng, L., Church, J., Desbruyeres, D., Dolman, H., Domingues, C. M., García-García, A., Giglio, D., Gilson, J. E., Gorfer, M., Haimberger, L., Hakuba, M. Z., Hendricks, S., Hosoda, S., Johnson, G. C., Killick, R., King, B., Kolodziejczyk, N., Korosov, A., Krinner, G., Kuusela, M., Landerer, F. W., Langer, M., Lavergne, T., Lawrence, I., Li, Y., Lyman, J., Marti, F., Marzeion, B., Mayer, M., MacDougall, A. H., McDougall, T., Monselesan, D. P., Nitzbon, J., Otosaka, I., Peng, J., Purkey, S., Roemmich, D., Sato, K., Sato, K., Savita, A., Schweiger, A., Shepherd, A., Seneviratne, S. I., Simons, L., Slater, D. A., Slater, T., Steiner, A. K., Suga, T., Szekely, T., Thiery, W., Timmermans, M.-L., Vanderkelen, I., Wjiffels, S. E., Wu, T., and Zemp, M.: Heat stored in the Earth system 1960–2020: where does the energy go?, Earth Syst. Sci. Data, 15, 1675–1709, https://doi.org/10.5194/essd-15-1675-2023, 2023.
Waelbroeck, C., Labeyrie, L., Michel, E., Duplessy, J. C., McManus, J. F., Lambeck, K., Balbon, E., and Labracherie, M.: Sea-level and deep water temperature changes derived from benthic foraminifera isotopic records, Quaternary Sci. Rev., 21, 295–305, 2002.
Weiffenbach, J. E., Dijkstra, H. A., von der Heydt, A. S., Abe-Ouchi, A., Chan, W.-L., Chandan, D., Feng, R., Haywood, A. M., Hunter, S. J., Li, X., Otto-Bliesner, B. L., Peltier, W. R., Stepanek, C., Tan, N., Tindall, J. C., and Zhang, Z.: Highly stratified mid-Pliocene Southern Ocean in PlioMIP2, Clim. Past, 20, 1067–1086, https://doi.org/10.5194/cp-20-1067-2024, 2024.
Westerhold, T., Marwan, N., Drury, A. J., Liebrand, D., Agnini, C., Anagnostou, E., Barnet, J. S. K., Bohaty, S. M., De Vleeschouwer, D., Florindo, F., Frederichs, T., Hodell, D. A., Holbourn, A. E., Kroon, D., Lauretano, V., Littler, K., Lourens, L. J., Lyle, M., Palike, H., Rohl, U., Tian, J., Wilkens, R. H., Wilson, P. A., and Zachos, J. C.: An astronomically dated record of Earth's climate and its predictability over the last 66 million years, Science, 369, 1383–1387, https://doi.org/10.1126/science.aba6853, 2020.
Winnick, M. J. and Caves, J. K.: Oxygen isotope mass-balance constraints on Pliocene sea level and East Antarctic Ice Sheet stability, Geology, 43, 879–882, https://doi.org/10.1130/g36999.1, 2015.
Woodard, S. C., Rosenthal, Y., Miller, K. G., Wright, J. D., Chiu, B. K., and Lawrence, K. T.: Antarctic role in Northern Hemisphere glaciation, Science, 346, 847–851, https://doi.org/10.1126/science.1255586, 2014.
Zachos, J., Pagani, M., Sloan, L., Thomas, E., and Billups, K.: Trends, rhythms, and aberrations in global climate 65 Ma to present, Science, 292, 686–693, https://doi.org/10.1126/science.1059412, 2001.
Zanna, L., Khatiwala, S., Gregory, J. M., Ison, J., and Heimbach, P.: Global reconstruction of historical ocean heat storage and transport, P. Natl. Acad. Sci. USA, 116, 1126–1131, https://doi.org/10.1073/pnas.1808838115, 2019.
Zeebe, R. E.: An explanation of the effect of seawater carbonate concentration on foraminiferal oxygen isotopes, Geochim. Cosmochim. Ac., 63, 2001–2007, https://doi.org/10.1016/s0016-7037(99)00091-5, 1999.
Zhou, S., Meijers, A. J. S., Meredith, M. P., Abrahamsen, E. P., Holland, P. R., Silvano, A., Sallée, J. B., and Østerhus, S.: Slowdown of Antarctic bottom water export driven by climatic wind and sea-ice change, Nat. Clim. Change, 13, 701–709, 2023.
Zhu, C., Sanchez, S., Liu, Z., Clark, P. U., He, C., Wan, L., Lu, J., Zhu, C., Li, L., Zhang, S., and Cheng, L.: Enhanced ocean heat storage efficiency during the last deglaciation, Science Advances, 10, eadp55156, https://doi.org/10.1088/1748-9326/ad2b2b, 2024.
Zhu, C. Y., Liu, Z. Y., Zhang, S. Q., and Wu, L. X.: Global oceanic overturning circulation forced by the competition between greenhouse gases and continental ice Sheets during the last deglaciation, J. Climate, 34, 7555–7570, https://doi.org/10.1175/jcli-d-21-0125.1, 2021.
Download
- Article
(14559 KB) - Full-text XML
Co-editor-in-chief
This Milankovic Medalist paper represents a tour de force, addressing a complex yet crucial question: the evolution of global climate over the past 4.5 million years. This paper makes a significant contribution to the geoscience community by providing a self-consistent decomposition of global mean benthic δ18O into its temperature and seawater (ice volume) components.
This approach is consistent with independent estimates of global mean sea surface temperature (GMSST) and sea level constraints.The analysis incorporates numerous high-resolution records spanning this period and highlights two distinct climatic regimes:
• Before 1.5 million years ago, a warm period characterized by smaller-amplitude ice sheet and sea level cycles, primarily driven by obliquity timescales.
• Following the Mid-Pleistocene Transition (MPT), i.e. after 1 million years, a well-documented increase in the amplitude of glacial cycles became evident.
The central finding of the study is that, during the MPT, there was a shift in ocean heat storage efficiency (HSE). Prior to this transition, HSE remained low and constant, whereas after the MPT, it doubled and stabilized at a higher value. This finding is supported by the observation of subtle differential changes in global mean SST and mean ocean temperature (MOT), which appear to be time-dependent. These observations suggest a potential fundamental shift in oceanic heat storage dynamics.
This Milankovic Medalist paper represents a tour de force, addressing a complex yet crucial...
Short summary
We reconstruct changes in mean ocean temperature (ΔMOT) over the last 4.5 Myr. We find that the ratio of ΔMOT to changes in global mean sea surface temperature was around 0.5 before the Middle Pleistocene transition but was 1 thereafter. We subtract our ΔMOT reconstruction from the global δ18O record to derive the δ18O of seawater. Finally, we develop a theoretical understanding of why the ratio of ΔMOT / ΔGMSST changed over the Plio-Pleistocene.
We reconstruct changes in mean ocean temperature (ΔMOT) over the last 4.5 Myr. We find that the...
Special issue