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2. The role of paleogeography in Asian monsoon evolution: Associated a review and new insights from climate modelling

Author

Tardif, D., primary, Sarr, A.-C., additional, Fluteau, F., additional, Licht, A., additional, Kaya, M., additional, Ladant, J.-B., additional, Meijer, N., additional, Donnadieu, Y., additional, Dupont-Nivet, G., additional, Bolton, C.T., additional, Le Hir, G., additional, Pillot, Q., additional, Poblete, F., additional, Sepulchre, P., additional, Toumoulin, A., additional, and Banfield, W., additional

Published
2023
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3. The relationship between the global mean deep-sea and surface temperature during the Early Eocene

Author

Goudsmit-Harzevoort, B., Lansu, A., Baatsen, M.L.J., von der Heydt, A.S., de Winter, N.J., Zhang, Y., Abe-Ouchi, A., de Boer, A.M., Chan, W.-L., Donnadieu, Y., Hutchinson, D.K., Knorr, G., Ladant, J.-B., Morozova, P., Niezgodzki, I., Steinig, S., Tripati, A.K., Zhang, Z., Zhu, J., Ziegler, M., Goudsmit-Harzevoort, B., Lansu, A., Baatsen, M.L.J., von der Heydt, A.S., de Winter, N.J., Zhang, Y., Abe-Ouchi, A., de Boer, A.M., Chan, W.-L., Donnadieu, Y., Hutchinson, D.K., Knorr, G., Ladant, J.-B., Morozova, P., Niezgodzki, I., Steinig, S., Tripati, A.K., Zhang, Z., Zhu, J., and Ziegler, M.

Abstract

Estimates of global mean near-surface air temperature (global SAT) for the Cenozoic era rely largely on paleo-proxy data of deep-sea temperature (DST), with the assumption that changes in global SAT covary with changes in the global mean deep-sea temperature (global DST) and global mean sea-surface temperature (global SST). We tested the validity of this assumption by analyzing the relationship between global SST, SAT, and DST using 25 different model simulations from the Deep-Time Model Intercomparison Project simulating the early Eocene Climatic Optimum (EECO) with varying CO2 levels. Similar to the modern situation, we find limited spatial variability in DST, indicating that local DST estimates can be regarded as a first order representative of global DST. In line with previously assumed relationships, linear regression analysis indicates that both global DST and SAT respond stronger to changes in atmospheric CO2 than global SST by a similar factor. Consequently, this model-based analysis validates the assumption that changes in global DST can be used to estimate changes in global SAT during the early Cenozoic. Paleo-proxy estimates of global DST, SST, and SAT during EECO show the best fit with model simulations with a 1,680 ppm atmospheric CO2 level. This matches paleo-proxies of EECO atmospheric CO2, indicating a good fit between models and proxy-data.

Published
2023

6. Asian monsoons in a late Eocene greenhouse world

Author

Licht, A., van Cappelle, M., Abels, H.A., Ladant, J.-B., Trabucho-Alexandre, J., France-Lanord, C., Donnadieu, Y., Vandenberghe, J., Rigaudier, T., Lecuyer, C., Terry, Jr., D., Adriaens, R., Boura, A., Guo, Z., Soe, Aung Naing, Quade, J., Dupont-Nivet, G., and Jaeger, J.-J.

Subjects
Topographical drawing -- Analysis, Atmospheric circulation -- Analysis, Winds -- Research, Monsoons -- Research, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan-Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55-34 Myr ago) are unknown because of the paucity of well- dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan-Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago., The Asian monsoon system controls precipitation over mainland Asia and is a critical component of modern global atmospheric circulation (1). During summer monsoons, high insolation over continental regions produces a [...]

Published
2014
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8. The Eocene–Oligocene transition: a review of marine and terrestrial proxy data, models and model–data comparisons

Author

Sub Dynamics Meteorology, Sub Physical Oceanography, Sub AW Hydrogeologie Externen, Marine and Atmospheric Research, Hutchinson, D. K., Coxall, H. K., Lunt, D. J., Steinthorsdottir, M., de Boer, A. M., Baatsen, M., von der Heydt, A., Huber, M., Kennedy-Asser, A. T., Kunzmann, L., Ladant, J.-B., Lear, C. H., Moraweck, K., Pearson, P. N., Piga, E., Pound, M. J., Salzmann, U., Scher, H. D., Sijp, W. P., Śliwińska, K. K., Wilson, P. A., Zhang, Z., Sub Dynamics Meteorology, Sub Physical Oceanography, Sub AW Hydrogeologie Externen, Marine and Atmospheric Research, Hutchinson, D. K., Coxall, H. K., Lunt, D. J., Steinthorsdottir, M., de Boer, A. M., Baatsen, M., von der Heydt, A., Huber, M., Kennedy-Asser, A. T., Kunzmann, L., Ladant, J.-B., Lear, C. H., Moraweck, K., Pearson, P. N., Piga, E., Pound, M. J., Salzmann, U., Scher, H. D., Sijp, W. P., Śliwińska, K. K., Wilson, P. A., and Zhang, Z.

Published
2021

9. Cenozoic evolution of the steppe-desert biome in Central Asia

Author

Barbolini, N., Woutersen, A., Dupont-Nivet, G., Silvestro, D., Tardif, D., Coster, P. M. C., Meijer, N., Chang, C., Zhang, H.-X., Licht, A., Rydin, C., Koutsodendris, A., Han, F., Rohrmann, A., Liu, X.-J., Zhang, Y., Donnadieu, Y., Fluteau, F., Ladant, J.-B., Le Hir, G., Hoorn, C., Ecosystem and Landscape Dynamics (IBED, FNWI), University of Amsterdam [Amsterdam] (UvA), University of Potsdam = Universität Potsdam, Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Key Laboratory of Orogenic Belts and Crustal Evolution, Peking University [Beijing], Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Modélisation du climat (CLIM), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), 649081, H2020 European Research Council, PCEFP3_187012, FN-1749, Schweizerischer Nationalfonds zur F&#x00F6, rderung der Wissenschaftlichen Forschung, Universität Potsdam, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Reviews, Geology, Review, SciAdv reviews
Abstract

The steppe-desert is much older than previously thought, but has evolved substantially from the Paleogene to the present., The origins and development of the arid and highly seasonal steppe-desert biome in Central Asia, the largest of its kind in the world, remain largely unconstrained by existing records. It is unclear how Cenozoic climatic, geological, and biological forces, acting at diverse spatial and temporal scales, shaped Central Asian ecosystems through time. Our synthesis shows that the Central Asian steppe-desert has existed since at least Eocene times but experienced no less than two regime shifts, one at the Eocene–Oligocene Transition and one in the mid-Miocene. These shifts separated three successive “stable states,” each characterized by unique floral and faunal structures. Past responses to disturbance in the Asian steppe-desert imply that modern ecosystems are unlikely to recover their present structures and diversity if forced into a new regime. This is of concern for Asian steppes today, which are being modified for human use and lost to desertification at unprecedented rates.

Published
2020

10. Cenozoic evolution of the steppe-desert biome in Central Asia

Author

Barbolini, Natasha, Woutersen, A., Dupont-Nivet, G., Silvestro, D., Tardif, D., Coster, P. M. C., Meijer, N., Chang, C., Zhang, H.-X., Licht, A., Rydin, Catarina, Koutsodendris, A., Han, F., Rohrmann, A., Liu, X.-J., Zhang, Y., Donnadieu, Y., Fluteau, F., Ladant, J.-B., Le Hir, G., Hoorn, C., Barbolini, Natasha, Woutersen, A., Dupont-Nivet, G., Silvestro, D., Tardif, D., Coster, P. M. C., Meijer, N., Chang, C., Zhang, H.-X., Licht, A., Rydin, Catarina, Koutsodendris, A., Han, F., Rohrmann, A., Liu, X.-J., Zhang, Y., Donnadieu, Y., Fluteau, F., Ladant, J.-B., Le Hir, G., and Hoorn, C.

Abstract

The origins and development of the arid and highly seasonal steppe-desert biome in Central Asia, the largest of its kind in the world, remain largely unconstrained by existing records. It is unclear how Cenozoic climatic, geological, and biological forces, acting at diverse spatial and temporal scales, shaped Central Asian ecosystems through time. Our synthesis shows that the Central Asian steppe-desert has existed since at least Eocene times but experienced no less than two regime shifts, one at the Eocene-Oligocene Transition and one in the mid-Miocene. These shifts separated three successive stable states, each characterized by unique floral and faunal structures. Past responses to disturbance in the Asian steppe-desert imply that modern ecosystems are unlikely to recover their present structures and diversity if forced into a new regime. This is of concern for Asian steppes today, which are being modified for human use and lost to desertification at unprecedented rates.

Published
2020
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12. The DeepMIP contribution to PMIP4: experimental design for model simulations of the EECO, PETM, and pre-PETM

Author

Lunt, D. J., Huber, M., Baatsen, M. L. J., Caballero, R., DeConto, R., Donnadieu, Y., Evans, D., Feng, R., Foster, G., Gasson, E., von der Heydt, A. S., Hollis, C. J., Kirtland Turner, S., Korty, R. L., Kozdon, R., Krishnan, S., Ladant, J. -B., Langebroek, P., Lear, C. H., LeGrande, A. N., Littler, K., Markwick, P., Otto-Bliesner, B., Pearson, P., Poulsen, C., Salzmann, U., Shields, C., Snell, K., Starz, M., Super, J., Tabour, C., Tierney, J., Tourte, G. J. L., Upchurch, G. R., Wade, B., Wing, S. L., Winguth, A. M. E., Wright, N., Zachos, J. C., Zeebe, R., Sub Physical Oceanography, and Marine and Atmospheric Research

Abstract

Past warm periods provide an opportunity to evaluate climate models under extreme forcing scenarios, in particular high (> 800 ppmv) atmospheric CO2 concentrations. Although a post-hoc intercomparison of Eocene (~50 million years ago, Ma) climate model simulations and geological data has been carried out previously, models of past high-CO2 periods have never been evaluated in a consistent framework. Here, we present an experimental design for climate model simulations of three warm periods within the latest Paleocene and the early Eocene. Together these form the first phase of DeepMIP – the deeptime model intercomparison project, itself a group within the wider Paleoclimate Modelling Intercomparison Project (PMIP). The experimental design consists of three core paleo simulations and a set of optional sensitivity studies. The experimental design specifies and provides guidance on boundary conditions associated with palaeogeography, greenhouse gases, orbital configuration, solar constant, land surface parameters, and aerosols. Initial conditions, simulation length, and output variables are also specified. Finally, we explain how the geological datasets, which will be used to evaluate the simulations, will be developed.

Published
2017

13. Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current

Author

Ladant, J.-B., Donnadieu, Yannick, Dumas, C., Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modélisation du climat (CLIM), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
lcsh:GE1-350, lcsh:Environmental pollution, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, lcsh:Environmental protection, lcsh:TD172-193.5, lcsh:TD169-171.8, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, lcsh:Environmental sciences
Abstract

International audience; The timing of the onset of the Antarctic Circum-polar Current (ACC) is a crucial event of the Cenozoic because of its cooling and isolating effect over Antarctica. It is intimately related to the glaciations occurring throughout the Cenozoic from the Eocene-Oligocene (EO) transition (≈ 34 Ma) to the middle Miocene glaciations (≈ 13.9 Ma). However, the exact timing of the onset remains debated, with evidence for a late Eocene setup contradicting other data pointing to an occurrence closer to the Oligocene-Miocene (OM) boundary. In this study, we show the potential impact of the Antarctic ice sheet on the initiation of a strong proto-ACC at the EO boundary. Our results reveal that the regional cooling effect of the ice sheet increases sea ice formation, which disrupts the meridional density gradient in the Southern Ocean and leads to the onset of a circumpolar current and its progressive strengthening. We also suggest that subsequent variations in atmospheric CO 2 , ice sheet volumes and tectonic reorganizations may have affected the ACC intensity after the Eocene-Oligocene transition. This allows us to build a hypothesis for the Cenozoic evolution of the Antarctic Circumpolar Current that may provide an explanation for the second initiation of the ACC at the Oligocene-Miocene boundary while reconciling evidence supporting both early Oligocene and early Miocene onset of the ACC.

Published
2014

14. The DeepMIP contribution to PMIP4: experimental design for model simulations of the EECO, PETM, and pre-PETM

Author

Sub Physical Oceanography, Marine and Atmospheric Research, Lunt, D. J., Huber, M., Baatsen, M. L. J., Caballero, R., DeConto, R., Donnadieu, Y., Evans, D., Feng, R., Foster, G., Gasson, E., von der Heydt, A. S., Hollis, C. J., Kirtland Turner, S., Korty, R. L., Kozdon, R., Krishnan, S., Ladant, J. -B., Langebroek, P., Lear, C. H., LeGrande, A. N., Littler, K., Markwick, P., Otto-Bliesner, B., Pearson, P., Poulsen, C., Salzmann, U., Shields, C., Snell, K., Starz, M., Super, J., Tabour, C., Tierney, J., Tourte, G. J. L., Upchurch, G. R., Wade, B., Wing, S. L., Winguth, A. M. E., Wright, N., Zachos, J. C., Zeebe, R., Sub Physical Oceanography, Marine and Atmospheric Research, Lunt, D. J., Huber, M., Baatsen, M. L. J., Caballero, R., DeConto, R., Donnadieu, Y., Evans, D., Feng, R., Foster, G., Gasson, E., von der Heydt, A. S., Hollis, C. J., Kirtland Turner, S., Korty, R. L., Kozdon, R., Krishnan, S., Ladant, J. -B., Langebroek, P., Lear, C. H., LeGrande, A. N., Littler, K., Markwick, P., Otto-Bliesner, B., Pearson, P., Poulsen, C., Salzmann, U., Shields, C., Snell, K., Starz, M., Super, J., Tabour, C., Tierney, J., Tourte, G. J. L., Upchurch, G. R., Wade, B., Wing, S. L., Winguth, A. M. E., Wright, N., Zachos, J. C., and Zeebe, R.

Published
2017

15. The DeepMIP contribution to PMIP4: experimental design for model simulations of the EECO, PETM, and pre-PETM (version 1.0)

Author

Lunt, D. J., Huber, M., Anagnostou, E., Baatsen, M. L. J., Caballero, R., DeConto, R., Dijkstra, H. A., Donnadieu, Y., Evans, D., Feng, R., Foster, G. L., Gasson, E., von der Heydt, A. S., Hollis, C. J., Inglis, G. N., Jones, S. M., Kiehl, J., Turner, S. K., Korty, R. L., Kozdon, R., Krishnan, S., Ladant, J.-B., Langebroek, P. M., Lear, C. H., LeGrande, A. N., Littler, K., Markwick, P., Otto-Bliesner, B., Pearson, P., Poulsen, C. J., Salzmann, U., Shields, C., Snell, K., Stärz, M., Super, J., Tabor, C., Tierney, J. E., Tourte, G. J. L., Tripati, A., Upchurch, G. R., Wade, B. S., Wing, S. L., Winguth, A. M. E., Wright, N. M., Zachos, J. C., Zeebe, Richard E., Lunt, D. J., Huber, M., Anagnostou, E., Baatsen, M. L. J., Caballero, R., DeConto, R., Dijkstra, H. A., Donnadieu, Y., Evans, D., Feng, R., Foster, G. L., Gasson, E., von der Heydt, A. S., Hollis, C. J., Inglis, G. N., Jones, S. M., Kiehl, J., Turner, S. K., Korty, R. L., Kozdon, R., Krishnan, S., Ladant, J.-B., Langebroek, P. M., Lear, C. H., LeGrande, A. N., Littler, K., Markwick, P., Otto-Bliesner, B., Pearson, P., Poulsen, C. J., Salzmann, U., Shields, C., Snell, K., Stärz, M., Super, J., Tabor, C., Tierney, J. E., Tourte, G. J. L., Tripati, A., Upchurch, G. R., Wade, B. S., Wing, S. L., Winguth, A. M. E., Wright, N. M., Zachos, J. C., and Zeebe, Richard E.

Abstract

Past warm periods provide an opportunity to evaluate climate models under extreme forcing scenarios, in particular high ( > 800 ppmv) atmospheric CO2 concentrations. Although a post hoc intercomparison of Eocene ( ∼ 50 Ma) climate model simulations and geological data has been carried out previously, models of past high-CO2 periods have never been evaluated in a consistent framework. Here, we present an experimental design for climate model simulations of three warm periods within the early Eocene and the latest Paleocene (the EECO, PETM, and pre-PETM). Together with the CMIP6 pre-industrial control and abrupt 4 × CO2 simulations, and additional sensitivity studies, these form the first phase of DeepMIP – the Deep-time Model Intercomparison Project, itself a group within the wider Paleoclimate Modelling Intercomparison Project (PMIP). The experimental design specifies and provides guidance on boundary conditions associated with palaeogeography, greenhouse gases, astronomical configuration, solar constant, land surface processes, and aerosols. Initial conditions, simulation length, and output variables are also specified. Finally, we explain how the geological data sets, which will be used to evaluate the simulations, will be developed.

Published
2017

16. Asian monsoons in a late Eocene greenhouse world

Author

NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VIDI: Is the collision between India and Asia responsible for global climate cooling?, Sedimentology, Stratigraphy and paleontology, Paleomagnetism, Licht, A., van Cappelle, M., Abels, H.A., Ladant, J.-B., Trabucho-Alexandre, J., France-Lanord, C., Donnadieu, Y., Vandenberghe, J., Rigaudier, T., Lécuyer, C., Terry, D., Adriaens, R., Boura, A., Guo, Z., Naing Soe, Aung, Quade, J., Dupont-Nivet, G., Jaeger, J.-J., NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VIDI: Is the collision between India and Asia responsible for global climate cooling?, Sedimentology, Stratigraphy and paleontology, Paleomagnetism, Licht, A., van Cappelle, M., Abels, H.A., Ladant, J.-B., Trabucho-Alexandre, J., France-Lanord, C., Donnadieu, Y., Vandenberghe, J., Rigaudier, T., Lécuyer, C., Terry, D., Adriaens, R., Boura, A., Guo, Z., Naing Soe, Aung, Quade, J., Dupont-Nivet, G., and Jaeger, J.-J.

Published
2014

18. Links between CO2, glaciation and water flow: reconciling the Cenozoic history of the Antarctic Circumpolar Current.

Author

Ladant, J.-B., Donnadieu, Y., and Dumas, C.

Abstract

The timing of the onset of the Antarctic Circumpolar Current (ACC) is a crucial event of the Cenozoic because of its cooling and isolating effect over Antarctica. It is intimately related to the glaciations occurring throughout the Cenozoic from the Eocene-Oligocene (EO) transition (≈34 Ma) to the middle Miocene glaciations (≈13.9 Ma). However, the exact timing of the onset remains debated with evidence for a late Eocene set up contradicting others data pointing to an occurrence closer to the Oligocene-Miocene (OM) boundary. In this study, we show the potential impact of the Antarctic ice sheet on the initiation of a proto-ACC at the EO boundary. Our results reveal that the regional cooling effect of the ice sheet increases the sea ice formation, which disrupts the meridional density gradient in the Southern Ocean and leads to the onset of a circumpolar current and its progressive strengthening. We also suggest that subsequent variations in atmospheric CO2, ice sheet volumes and tectonic reorganizations may have affected the ACC intensity after the Eocene-Oligocene transition, which in turn may provide an explanation for the second initiation of the ACC at the Oligocene-Miocene boundary and may reconcile evidence supporting both early Oligocene and early Miocene onset of the ACC. [ABSTRACT FROM AUTHOR]

Published
2014
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19. Cenozoic evolution of the steppe-desert biome in Central Asia

Author

Barbolini, N., Woutersen, A., Dupont-Nivet, G., Silvestro, Daniele, Tardif, D., Coster, P. M. C., Meijer, N., Chang, C., Zhang, H.-X., Licht, A., Rydin, C., Koutsodendris, A., Han, F., Rohrmann, A., Liu, X.-J., Zhang, Y., Donnadieu, Y., Fluteau, F., Ladant, J.-B., Le Hir, G., Hoorn, C., Barbolini, N., Woutersen, A., Dupont-Nivet, G., Silvestro, Daniele, Tardif, D., Coster, P. M. C., Meijer, N., Chang, C., Zhang, H.-X., Licht, A., Rydin, C., Koutsodendris, A., Han, F., Rohrmann, A., Liu, X.-J., Zhang, Y., Donnadieu, Y., Fluteau, F., Ladant, J.-B., Le Hir, G., and Hoorn, C.

Abstract

The origins and development of the arid and highly seasonal steppe-desert biome in Central Asia, the largest of its kind in the world, remain largely unconstrained by existing records. It is unclear how Cenozoic climatic, geological, and biological forces, acting at diverse spatial and temporal scales, shaped Central Asian ecosystems through time. Our synthesis shows that the Central Asian steppe-desert has existed since at least Eocene times but experienced no less than two regime shifts, one at the Eocene–Oligocene Transition and one in the mid-Miocene. These shifts separated three successive “stable states,” each characterized by unique floral and faunal structures. Past responses to disturbance in the Asian steppe-desert imply that modern ecosystems are unlikely to recover their present structures and diversity if forced into a new regime. This is of concern for Asian steppes today, which are being modified for human use and lost to desertification at unprecedented rates.

20. Cenozoic evolution of the steppe-desert biome in Central Asia.

Author

Barbolini N, Woutersen A, Dupont-Nivet G, Silvestro D, Tardif D, Coster PMC, Meijer N, Chang C, Zhang HX, Licht A, Rydin C, Koutsodendris A, Han F, Rohrmann A, Liu XJ, Zhang Y, Donnadieu Y, Fluteau F, Ladant JB, Le Hir G, and Hoorn C

Abstract

The origins and development of the arid and highly seasonal steppe-desert biome in Central Asia, the largest of its kind in the world, remain largely unconstrained by existing records. It is unclear how Cenozoic climatic, geological, and biological forces, acting at diverse spatial and temporal scales, shaped Central Asian ecosystems through time. Our synthesis shows that the Central Asian steppe-desert has existed since at least Eocene times but experienced no less than two regime shifts, one at the Eocene-Oligocene Transition and one in the mid-Miocene. These shifts separated three successive "stable states," each characterized by unique floral and faunal structures. Past responses to disturbance in the Asian steppe-desert imply that modern ecosystems are unlikely to recover their present structures and diversity if forced into a new regime. This is of concern for Asian steppes today, which are being modified for human use and lost to desertification at unprecedented rates., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Published
2020
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