Articles | Volume 16, issue 4
https://doi.org/10.5194/cp-16-1263-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-16-1263-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Jul 2020
Research article |
| 17 Jul 2020
| 17 Jul 2020
Early Eocene vigorous ocean overturning and its contribution to a warm Southern Ocean
Univ Brest, CNRS, IRD, Ifremer, Laboratoire d'Océanographie
Physique et Spatiale (LOPS), IUEM, Brest, France
Thierry Huck
Univ Brest, CNRS, IRD, Ifremer, Laboratoire d'Océanographie
Physique et Spatiale (LOPS), IUEM, Brest, France
Camille Lique
Univ Brest, CNRS, IRD, Ifremer, Laboratoire d'Océanographie
Physique et Spatiale (LOPS), IUEM, Brest, France
Yannick Donnadieu
Laboratoire des Sciences du Climat et de l'Environnement, LSCE-IPSL,
CEA/CNRS/UVSQ, Université Paris-Saclay, Gif-sur-Yvette, France
Aix Marseille Univ, CNRS, IRD, INRA, Coll France, CEREGE,
Aix-en-Provence, France
Jean-Baptiste Ladant
Department of Earth and Environmental Sciences, University of
Michigan, Ann Arbor, MI, USA
Marina Rabineau
CNRS, Univ Brest, Univ Bretagne Sud, Laboratoire Géosciences
Océan (LGO, UMR6538), IUEM, Plouzané, France
Daniel Aslanian
Ifremer, Unité de Recherche Géosciences Marines, Centre de
Bretagne, Plouzané, France
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Sofia Allende, Anne Marie Treguier, Camille Lique, Clément de Boyer Montégut, François Massonnet, Thierry Fichefet, and Antoine Barthélemy
Geosci. Model Dev., 17, 7445–7466, https://doi.org/10.5194/gmd-17-7445-2024, https://doi.org/10.5194/gmd-17-7445-2024, 2024
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We study the parameters of the turbulent-kinetic-energy mixed-layer-penetration scheme in the NEMO model with regard to sea-ice-covered regions of the Arctic Ocean. This evaluation reveals the impact of these parameters on mixed-layer depth, sea surface temperature and salinity, and ocean stratification. Our findings demonstrate significant impacts on sea ice thickness and sea ice concentration, emphasizing the need for accurately representing ocean mixing to understand Arctic climate dynamics.
Dongyu Zheng, Andrew S. Merdith, Yves Goddéris, Yannick Donnadieu, Khushboo Gurung, and Benjamin J. W. Mills
Geosci. Model Dev., 17, 5413–5429, https://doi.org/10.5194/gmd-17-5413-2024, https://doi.org/10.5194/gmd-17-5413-2024, 2024
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This study uses a deep learning method to upscale the time resolution of paleoclimate simulations to 1 million years. This improved resolution allows a climate-biogeochemical model to more accurately predict climate shifts. The method may be critical in developing new fully continuous methods that are able to be applied over a moving continental surface in deep time with high resolution at reasonable computational expense.
Anne Marie Treguier, Clement de Boyer Montégut, Alexandra Bozec, Eric P. Chassignet, Baylor Fox-Kemper, Andy McC. Hogg, Doroteaciro Iovino, Andrew E. Kiss, Julien Le Sommer, Yiwen Li, Pengfei Lin, Camille Lique, Hailong Liu, Guillaume Serazin, Dmitry Sidorenko, Qiang Wang, Xiaobio Xu, and Steve Yeager
Geosci. Model Dev., 16, 3849–3872, https://doi.org/10.5194/gmd-16-3849-2023, https://doi.org/10.5194/gmd-16-3849-2023, 2023
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The ocean mixed layer is the interface between the ocean interior and the atmosphere and plays a key role in climate variability. We evaluate the performance of the new generation of ocean models for climate studies, designed to resolve
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Guillaume Boutin, Einar Ólason, Pierre Rampal, Heather Regan, Camille Lique, Claude Talandier, Laurent Brodeau, and Robert Ricker
The Cryosphere, 17, 617–638, https://doi.org/10.5194/tc-17-617-2023, https://doi.org/10.5194/tc-17-617-2023, 2023
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Sea ice cover in the Arctic is full of cracks, which we call leads. We suspect that these leads play a role for atmosphere–ocean interactions in polar regions, but their importance remains challenging to estimate. We use a new ocean–sea ice model with an original way of representing sea ice dynamics to estimate their impact on winter sea ice production. This model successfully represents sea ice evolution from 2000 to 2018, and we find that about 30 % of ice production takes place in leads.
Agathe Toumoulin, Delphine Tardif, Yannick Donnadieu, Alexis Licht, Jean-Baptiste Ladant, Lutz Kunzmann, and Guillaume Dupont-Nivet
Clim. Past, 18, 341–362, https://doi.org/10.5194/cp-18-341-2022, https://doi.org/10.5194/cp-18-341-2022, 2022
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Temperature seasonality is an important climate parameter for biodiversity. Fossil plants describe its middle Eocene to early Oligocene increase in the Northern Hemisphere, but underlying mechanisms have not been studied in detail yet. Using climate simulations, we map global seasonality changes and show that major contemporary forcing – atmospheric CO2 lowering, Antarctic ice-sheet expansion and particularly related sea level drop – participated in this phenomenon and its spatial distribution.
Mikael Evain, Philippe Schnürle, Angélique Leprêtre, Fanny Verrier, Louise Watremez, Joseph Offei Thompson, Philippe de Clarens, Daniel Aslanian, and Maryline Moulin
Solid Earth, 12, 1865–1897, https://doi.org/10.5194/se-12-1865-2021, https://doi.org/10.5194/se-12-1865-2021, 2021
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This study analyses recently acquired marine seismic data offshore of southeastern Mozambique. It aims to better constrain the early history and formation of southeastern African margins. The crustal structure and segmentation of the Limpopo margin provide evidence of strike-slip rifting along the eastern North Natal Valley. This has profound consequences on our understanding of the East Gondwana breakup, challenging kinematic models based on an overlap between the Antarctic and African plates.
Guillaume Boutin, Timothy Williams, Pierre Rampal, Einar Olason, and Camille Lique
The Cryosphere, 15, 431–457, https://doi.org/10.5194/tc-15-431-2021, https://doi.org/10.5194/tc-15-431-2021, 2021
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In this study, we investigate the interactions of surface ocean waves with sea ice. We focus on the evolution of sea ice after it has been fragmented by the waves. Fragmented sea ice is expected to experience less resistance to deformation. We reproduce this evolution using a new coupling framework between a wave model and the recently developed sea ice model neXtSIM. We find that waves can significantly increase the mobility of compact sea ice over wide areas in the wake of storm events.
David K. Hutchinson, Helen K. Coxall, Daniel J. Lunt, Margret Steinthorsdottir, Agatha M. de Boer, Michiel Baatsen, Anna von der Heydt, Matthew Huber, Alan T. Kennedy-Asser, Lutz Kunzmann, Jean-Baptiste Ladant, Caroline H. Lear, Karolin Moraweck, Paul N. Pearson, Emanuela Piga, Matthew J. Pound, Ulrich Salzmann, Howie D. Scher, Willem P. Sijp, Kasia K. Śliwińska, Paul A. Wilson, and Zhongshi Zhang
Clim. Past, 17, 269–315, https://doi.org/10.5194/cp-17-269-2021, https://doi.org/10.5194/cp-17-269-2021, 2021
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The Eocene–Oligocene transition was a major climate cooling event from a largely ice-free world to the first major glaciation of Antarctica, approximately 34 million years ago. This paper reviews observed changes in temperature, CO2 and ice sheets from marine and land-based records at this time. We present a new model–data comparison of this transition and find that CO2-forced cooling provides the best explanation of the observed global temperature changes.
Daniel J. Lunt, Fran Bragg, Wing-Le Chan, David K. Hutchinson, Jean-Baptiste Ladant, Polina Morozova, Igor Niezgodzki, Sebastian Steinig, Zhongshi Zhang, Jiang Zhu, Ayako Abe-Ouchi, Eleni Anagnostou, Agatha M. de Boer, Helen K. Coxall, Yannick Donnadieu, Gavin Foster, Gordon N. Inglis, Gregor Knorr, Petra M. Langebroek, Caroline H. Lear, Gerrit Lohmann, Christopher J. Poulsen, Pierre Sepulchre, Jessica E. Tierney, Paul J. Valdes, Evgeny M. Volodin, Tom Dunkley Jones, Christopher J. Hollis, Matthew Huber, and Bette L. Otto-Bliesner
Clim. Past, 17, 203–227, https://doi.org/10.5194/cp-17-203-2021, https://doi.org/10.5194/cp-17-203-2021, 2021
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This paper presents the first modelling results from the Deep-Time Model Intercomparison Project (DeepMIP), in which we focus on the early Eocene climatic optimum (EECO, 50 million years ago). We show that, in contrast to previous work, at least three models (CESM, GFDL, and NorESM) produce climate states that are consistent with proxy indicators of global mean temperature and polar amplification, and they achieve this at a CO2 concentration that is consistent with the CO2 proxy record.
Pierre Sepulchre, Arnaud Caubel, Jean-Baptiste Ladant, Laurent Bopp, Olivier Boucher, Pascale Braconnot, Patrick Brockmann, Anne Cozic, Yannick Donnadieu, Jean-Louis Dufresne, Victor Estella-Perez, Christian Ethé, Frédéric Fluteau, Marie-Alice Foujols, Guillaume Gastineau, Josefine Ghattas, Didier Hauglustaine, Frédéric Hourdin, Masa Kageyama, Myriam Khodri, Olivier Marti, Yann Meurdesoif, Juliette Mignot, Anta-Clarisse Sarr, Jérôme Servonnat, Didier Swingedouw, Sophie Szopa, and Delphine Tardif
Geosci. Model Dev., 13, 3011–3053, https://doi.org/10.5194/gmd-13-3011-2020, https://doi.org/10.5194/gmd-13-3011-2020, 2020
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Our paper describes IPSL-CM5A2, an Earth system model that can be integrated for long (several thousands of years) climate simulations. We describe the technical aspects, assess the model computing performance and evaluate the strengths and weaknesses of the model, by comparing pre-industrial and historical runs to the previous-generation model simulations and to observations. We also present a Cretaceous simulation as a case study to show how the model simulates deep-time paleoclimates.
Jean-Baptiste Ladant, Christopher J. Poulsen, Frédéric Fluteau, Clay R. Tabor, Kenneth G. MacLeod, Ellen E. Martin, Shannon J. Haynes, and Masoud A. Rostami
Clim. Past, 16, 973–1006, https://doi.org/10.5194/cp-16-973-2020, https://doi.org/10.5194/cp-16-973-2020, 2020
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Understanding of the role of ocean circulation on climate is contingent on the ability to reconstruct its modes and evolution. Here, we show that earth system model simulations of the Late Cretaceous predict major changes in ocean circulation as a result of paleogeographic and gateway evolution. Comparisons of model results with available data compilations demonstrate reasonable agreement but highlight that various plausible theories of ocean circulation change coexist during this period.
Marie Laugié, Yannick Donnadieu, Jean-Baptiste Ladant, J. A. Mattias Green, Laurent Bopp, and François Raisson
Clim. Past, 16, 953–971, https://doi.org/10.5194/cp-16-953-2020, https://doi.org/10.5194/cp-16-953-2020, 2020
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To quantify the impact of major climate forcings on the Cretaceous climate, we use Earth system modelling to progressively reconstruct the Cretaceous state by changing boundary conditions one by one. Between the preindustrial and the Cretaceous simulations, the model simulates a global warming of more than 11°C. The study confirms the primary control exerted by atmospheric CO2 on atmospheric temperatures. Palaeogeographic changes represent the second major contributor to the warming.
Delphine Tardif, Frédéric Fluteau, Yannick Donnadieu, Guillaume Le Hir, Jean-Baptiste Ladant, Pierre Sepulchre, Alexis Licht, Fernando Poblete, and Guillaume Dupont-Nivet
Clim. Past, 16, 847–865, https://doi.org/10.5194/cp-16-847-2020, https://doi.org/10.5194/cp-16-847-2020, 2020
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The Asian monsoons onset has been suggested to be as early as 40 Ma, in a palaeogeographic and climatic context very different from modern conditions. We test the likeliness of an early monsoon onset through climatic modelling. Our results reveal a very arid central Asia and several regions in India, Myanmar and eastern China experiencing highly seasonal precipitations. This suggests that monsoon circulation is not paramount in triggering the highly seasonal patterns recorded in the fossils.
Alan T. Kennedy-Asser, Daniel J. Lunt, Paul J. Valdes, Jean-Baptiste Ladant, Joost Frieling, and Vittoria Lauretano
Clim. Past, 16, 555–573, https://doi.org/10.5194/cp-16-555-2020, https://doi.org/10.5194/cp-16-555-2020, 2020
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Global cooling and a major expansion of ice over Antarctica occurred ~ 34 million years ago at the Eocene–Oligocene transition (EOT). A large secondary proxy dataset for high-latitude Southern Hemisphere temperature before, after and across the EOT is compiled and compared to simulations from two coupled climate models. Although there are inconsistencies between the models and data, the comparison shows amongst other things that changes in the Drake Passage were unlikely the cause of the EOT.
Guillaume Boutin, Camille Lique, Fabrice Ardhuin, Clément Rousset, Claude Talandier, Mickael Accensi, and Fanny Girard-Ardhuin
The Cryosphere, 14, 709–735, https://doi.org/10.5194/tc-14-709-2020, https://doi.org/10.5194/tc-14-709-2020, 2020
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We investigate the interactions of surface ocean waves with sea ice taking place at the interface between the compact sea ice cover and the open ocean. We use a newly developed coupling framework between a wave and an ocean–sea ice numerical model. Our results show how the push on sea ice exerted by waves changes the amount and the location of sea ice melting, with a strong impact on the ocean surface properties close to the ice edge.
Robert Ricker, Fanny Girard-Ardhuin, Thomas Krumpen, and Camille Lique
The Cryosphere, 12, 3017–3032, https://doi.org/10.5194/tc-12-3017-2018, https://doi.org/10.5194/tc-12-3017-2018, 2018
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We present ice volume flux estimates through the Fram Strait using CryoSat-2 ice thickness data. This study presents a detailed analysis of temporal and spatial variability of ice volume export through the Fram Strait and shows the impact of ice volume export on Arctic ice mass balance.
Daniel J. Lunt, Matthew Huber, Eleni Anagnostou, Michiel L. J. Baatsen, Rodrigo Caballero, Rob DeConto, Henk A. Dijkstra, Yannick Donnadieu, David Evans, Ran Feng, Gavin L. Foster, Ed Gasson, Anna S. von der Heydt, Chris J. Hollis, Gordon N. Inglis, Stephen M. Jones, Jeff Kiehl, Sandy Kirtland Turner, Robert L. Korty, Reinhardt Kozdon, Srinath Krishnan, Jean-Baptiste Ladant, Petra Langebroek, Caroline H. Lear, Allegra N. LeGrande, Kate Littler, Paul Markwick, Bette Otto-Bliesner, Paul Pearson, Christopher J. Poulsen, Ulrich Salzmann, Christine Shields, Kathryn Snell, Michael Stärz, James Super, Clay Tabor, Jessica E. Tierney, Gregory J. L. Tourte, Aradhna Tripati, Garland R. Upchurch, Bridget S. Wade, Scott L. Wing, Arne M. E. Winguth, Nicky M. Wright, James C. Zachos, and Richard E. Zeebe
Geosci. Model Dev., 10, 889–901, https://doi.org/10.5194/gmd-10-889-2017, https://doi.org/10.5194/gmd-10-889-2017, 2017
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In this paper we describe the experimental design for a set of simulations which will be carried out by a range of climate models, all investigating the climate of the Eocene, about 50 million years ago. The intercomparison of model results is called 'DeepMIP', and we anticipate that we will contribute to the next IPCC report through an analysis of these simulations and the geological data to which we will compare them.
Svetlana Botsyun, Pierre Sepulchre, Camille Risi, and Yannick Donnadieu
Clim. Past, 12, 1401–1420, https://doi.org/10.5194/cp-12-1401-2016, https://doi.org/10.5194/cp-12-1401-2016, 2016
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We use an isotope-equipped GCM and develop original theoretical expression for the precipitation composition to assess δ18O of paleo-precipitation changes with the Tibetan Plateau uplift. We show that δ18O of precipitation is very sensitive to climate changes related to the growth of mountains, notably changes in relative humidity and precipitation amount. Topography is shown to be not an exclusive controlling factor δ18O in precipitation that have crucial consequences for paleoelevation studies
G. Hoareau, B. Bomou, D. J. J. van Hinsbergen, N. Carry, D. Marquer, Y. Donnadieu, G. Le Hir, B. Vrielynck, and A.-V. Walter-Simonnet
Clim. Past, 11, 1751–1767, https://doi.org/10.5194/cp-11-1751-2015, https://doi.org/10.5194/cp-11-1751-2015, 2015
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The impact of Neo-Tethys closure on early Cenozoic warming has been tested. First, the volume of subducted sediments and the amount of CO2 emitted along the northern Tethys margin has been calculated. Second, corresponding pCO2 have been tested using the GEOCLIM model. Despite high CO2 production, maximum pCO2 values (750ppm) do not reach values inferred from proxies. Other cited sources of excess CO2 such as the NAIP are also below fluxes required by GEOCLIM to fit with proxy data.
A. Pohl, Y. Donnadieu, G. Le Hir, J.-F. Buoncristiani, and E. Vennin
Clim. Past, 10, 2053–2066, https://doi.org/10.5194/cp-10-2053-2014, https://doi.org/10.5194/cp-10-2053-2014, 2014
J.-B. Ladant, Y. Donnadieu, and C. Dumas
Clim. Past, 10, 1957–1966, https://doi.org/10.5194/cp-10-1957-2014, https://doi.org/10.5194/cp-10-1957-2014, 2014
G. Le Hir, Y. Teitler, F. Fluteau, Y. Donnadieu, and P. Philippot
Clim. Past, 10, 697–713, https://doi.org/10.5194/cp-10-697-2014, https://doi.org/10.5194/cp-10-697-2014, 2014
Related subject area
Subject: Ocean Dynamics | Archive: Modelling only | Timescale: Cenozoic
The sensitivity of the Eocene–Oligocene Southern Ocean to the strength and position of wind stress
Changes in Mediterranean circulation and water characteristics due to restriction of the Atlantic connection: a high-resolution ocean model
Qianjiang Xing, David Munday, Andreas Klocker, Isabel Sauermilch, and Joanne Whittaker
Clim. Past, 18, 2669–2693, https://doi.org/10.5194/cp-18-2669-2022, https://doi.org/10.5194/cp-18-2669-2022, 2022
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A high-resolution ocean model and realistic paleo-bathymetry are applied to obtain accurate simulation results. We firstly propose that the alignment of the maximum wind stress with a deep Tasmanian Gateway and Drake Passage is a trigger for the proto-Antarctic Circumpolar Current (proto-ACC) and the cooling of the Eocene Southern Ocean. We use zonal momentum budget analysis to explore the nature of the proto-ACC and the sensitivity of its transport through gateways to doubled wind stress.
R. P. M. Topper and P. Th. Meijer
Clim. Past, 11, 233–251, https://doi.org/10.5194/cp-11-233-2015, https://doi.org/10.5194/cp-11-233-2015, 2015
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Short summary
The early Eocene (~ 55 Ma) was an extreme warm period accompanied by a high atmospheric CO2 level. We explore the relationships between ocean dynamics and this warm climate with the aid of the IPSL climate model. Our results show that the Eocene was characterized by a strong overturning circulation associated with deepwater formation in the Southern Ocean, which is analogous to the present-day North Atlantic. Consequently, poleward ocean heat transport was strongly enhanced.
The early Eocene (~ 55 Ma) was an extreme warm period accompanied by a high atmospheric CO2...
