Articles | Volume 10, issue 2
https://doi.org/10.5194/cp-10-523-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/cp-10-523-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
13 Mar 2014
Research article |
| 13 Mar 2014
The challenge of simulating the warmth of the mid-Miocene climatic optimum in CESM1
A. Goldner
Earth, Atmospheric, and Planetary Sciences, Purdue University, 550 Stadium Mall Drive, West Lafayette, IN 47907, USA
American Geophysical Union Congressional Science Fellow, Washington D.C., USA
N. Herold
Earth Systems Research Center, Institute for Earth, Ocean and Space Sciences, University of New Hampshire, Durham, NH 03824, USA
Department of Earth Sciences, The University of New Hampshire, Durham, NH 03824, USA
Earth Systems Research Center, Institute for Earth, Ocean and Space Sciences, University of New Hampshire, Durham, NH 03824, USA
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Related subject area
Subject: Climate Modelling | Archive: Modelling only | Timescale: Cenozoic
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Sensitivity of the Eocene climate to CO2 and orbital variability
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Changes to the tropical circulation in the mid-Pliocene and their implications for future climate
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Arctic sea ice simulation in the PlioMIP ensemble
The Pliocene Model Intercomparison Project (PlioMIP) Phase 2: scientific objectives and experimental design
Tropical cyclone genesis potential across palaeoclimates
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Interannual climate variability seen in the Pliocene Model Intercomparison Project
Ice sheet model dependency of the simulated Greenland Ice Sheet in the mid-Pliocene
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Modelling global-scale climate impacts of the late Miocene Messinian Salinity Crisis
Uncertainties in the modelled CO2 threshold for Antarctic glaciation
Investigating vegetation–climate feedbacks during the early Eocene
Evaluating the dominant components of warming in Pliocene climate simulations
The role of eastern Tethys seaway closure in the Middle Miocene Climatic Transition (ca. 14 Ma)
Mid-Pliocene East Asian monsoon climate simulated in the PlioMIP
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Xin Ren, Daniel J. Lunt, Erica Hendy, Anna von der Heydt, Ayako Abe-Ouchi, Bette Otto-Bliesner, Charles J. R. Williams, Christian Stepanek, Chuncheng Guo, Deepak Chandan, Gerrit Lohmann, Julia C. Tindall, Linda E. Sohl, Mark A. Chandler, Masa Kageyama, Michiel L. J. Baatsen, Ning Tan, Qiong Zhang, Ran Feng, Stephen Hunter, Wing-Le Chan, W. Richard Peltier, Xiangyu Li, Youichi Kamae, Zhongshi Zhang, and Alan M. Haywood
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Lauren E. Burton, Alan M. Haywood, Julia C. Tindall, Aisling M. Dolan, Daniel J. Hill, Ayako Abe-Ouchi, Wing-Le Chan, Deepak Chandan, Ran Feng, Stephen J. Hunter, Xiangyu Li, W. Richard Peltier, Ning Tan, Christian Stepanek, and Zhongshi Zhang
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Warm climates of the Pliocene (~ 3 million years ago) are similar to projections of the near future. We find elevated concentrations of atmospheric carbon dioxide to be the most important forcing for driving changes in Pliocene surface air temperature, sea surface temperature, and precipitation. However, changes caused by the nature of Pliocene ice sheets and orography are also important, affecting the extent to which we can use the Pliocene as an analogue for our warmer future.
Julia E. Weiffenbach, Michiel L. J. Baatsen, Henk A. Dijkstra, Anna S. von der Heydt, Ayako Abe-Ouchi, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Mark A. Chandler, Camille Contoux, Ran Feng, Chuncheng Guo, Zixuan Han, Alan M. Haywood, Qiang Li, Xiangyu Li, Gerrit Lohmann, Daniel J. Lunt, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Gilles Ramstein, Linda E. Sohl, Christian Stepanek, Ning Tan, Julia C. Tindall, Charles J. R. Williams, Qiong Zhang, and Zhongshi Zhang
Clim. Past, 19, 61–85, https://doi.org/10.5194/cp-19-61-2023, https://doi.org/10.5194/cp-19-61-2023, 2023
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We study the behavior of the Atlantic Meridional Overturning Circulation (AMOC) in the mid-Pliocene. The mid-Pliocene was about 3 million years ago and had a similar CO2 concentration to today. We show that the stronger AMOC during this period relates to changes in geography and that this has a significant influence on ocean temperatures and heat transported northwards by the Atlantic Ocean. Understanding the behavior of the mid-Pliocene AMOC can help us to learn more about our future climate.
Michiel L. J. Baatsen, Anna S. von der Heydt, Michael A. Kliphuis, Arthur M. Oldeman, and Julia E. Weiffenbach
Clim. Past, 18, 657–679, https://doi.org/10.5194/cp-18-657-2022, https://doi.org/10.5194/cp-18-657-2022, 2022
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The Pliocene was a period during which atmospheric CO2 was similar to today (i.e. ~ 400 ppm). We present the results of model simulations carried out within the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2) using the CESM 1.0.5. We find a climate that is much warmer than today, with augmented polar warming, increased precipitation, and strongly reduced sea ice cover. In addition, several leading modes of variability in temperature show an altered behaviour.
Zixuan Han, Qiong Zhang, Qiang Li, Ran Feng, Alan M. Haywood, Julia C. Tindall, Stephen J. Hunter, Bette L. Otto-Bliesner, Esther C. Brady, Nan Rosenbloom, Zhongshi Zhang, Xiangyu Li, Chuncheng Guo, Kerim H. Nisancioglu, Christian Stepanek, Gerrit Lohmann, Linda E. Sohl, Mark A. Chandler, Ning Tan, Gilles Ramstein, Michiel L. J. Baatsen, Anna S. von der Heydt, Deepak Chandan, W. Richard Peltier, Charles J. R. Williams, Daniel J. Lunt, Jianbo Cheng, Qin Wen, and Natalie J. Burls
Clim. Past, 17, 2537–2558, https://doi.org/10.5194/cp-17-2537-2021, https://doi.org/10.5194/cp-17-2537-2021, 2021
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Understanding the potential processes responsible for large-scale hydrological cycle changes in a warmer climate is of great importance. Our study implies that an imbalance in interhemispheric atmospheric energy during the mid-Pliocene could have led to changes in the dynamic effect, offsetting the thermodynamic effect and, hence, altering mid-Pliocene hydroclimate cycling. Moreover, a robust westward shift in the Pacific Walker circulation can moisten the northern Indian Ocean.
Arthur M. Oldeman, Michiel L. J. Baatsen, Anna S. von der Heydt, Henk A. Dijkstra, Julia C. Tindall, Ayako Abe-Ouchi, Alice R. Booth, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Mark A. Chandler, Camille Contoux, Ran Feng, Chuncheng Guo, Alan M. Haywood, Stephen J. Hunter, Youichi Kamae, Qiang Li, Xiangyu Li, Gerrit Lohmann, Daniel J. Lunt, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Gabriel M. Pontes, Gilles Ramstein, Linda E. Sohl, Christian Stepanek, Ning Tan, Qiong Zhang, Zhongshi Zhang, Ilana Wainer, and Charles J. R. Williams
Clim. Past, 17, 2427–2450, https://doi.org/10.5194/cp-17-2427-2021, https://doi.org/10.5194/cp-17-2427-2021, 2021
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In this work, we have studied the behaviour of El Niño events in the mid-Pliocene, a period of around 3 million years ago, using a collection of 17 climate models. It is an interesting period to study, as it saw similar atmospheric carbon dioxide levels to the present day. We find that the El Niño events were less strong in the mid-Pliocene simulations, when compared to pre-industrial climate. Our results could help to interpret El Niño behaviour in future climate projections.
Katherine A. Crichton, Andy Ridgwell, Daniel J. Lunt, Alex Farnsworth, and Paul N. Pearson
Clim. Past, 17, 2223–2254, https://doi.org/10.5194/cp-17-2223-2021, https://doi.org/10.5194/cp-17-2223-2021, 2021
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The middle Miocene (15 Ma) was a period of global warmth up to 8 °C warmer than present. We investigate changes in ocean circulation and heat distribution since the middle Miocene and the cooling to the present using the cGENIE Earth system model. We create seven time slices at ~2.5 Myr intervals, constrained with paleo-proxy data, showing a progressive reduction in atmospheric CO2 and a strengthening of the Atlantic Meridional Overturning Circulation.
Charles J. R. Williams, Alistair A. Sellar, Xin Ren, Alan M. Haywood, Peter Hopcroft, Stephen J. Hunter, William H. G. Roberts, Robin S. Smith, Emma J. Stone, Julia C. Tindall, and Daniel J. Lunt
Clim. Past, 17, 2139–2163, https://doi.org/10.5194/cp-17-2139-2021, https://doi.org/10.5194/cp-17-2139-2021, 2021
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Computer simulations of the geological past are an important tool to improve our understanding of climate change. We present results from a simulation of the mid-Pliocene (approximately 3 million years ago) using the latest version of the UK’s climate model. The simulation reproduces temperatures as expected and shows some improvement relative to previous versions of the same model. The simulation is, however, arguably too warm when compared to other models and available observations.
Ellen Berntell, Qiong Zhang, Qiang Li, Alan M. Haywood, Julia C. Tindall, Stephen J. Hunter, Zhongshi Zhang, Xiangyu Li, Chuncheng Guo, Kerim H. Nisancioglu, Christian Stepanek, Gerrit Lohmann, Linda E. Sohl, Mark A. Chandler, Ning Tan, Camille Contoux, Gilles Ramstein, Michiel L. J. Baatsen, Anna S. von der Heydt, Deepak Chandan, William Richard Peltier, Ayako Abe-Ouchi, Wing-Le Chan, Youichi Kamae, Charles J. R. Williams, Daniel J. Lunt, Ran Feng, Bette L. Otto-Bliesner, and Esther C. Brady
Clim. Past, 17, 1777–1794, https://doi.org/10.5194/cp-17-1777-2021, https://doi.org/10.5194/cp-17-1777-2021, 2021
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The mid-Pliocene Warm Period (~ 3.2 Ma) is often considered an analogue for near-future climate projections, and model results from the PlioMIP2 ensemble show an increase of rainfall over West Africa and the Sahara region compared to pre-industrial conditions. Though previous studies of future projections show a west–east drying–wetting contrast over the Sahel, these results indicate a uniform rainfall increase over the Sahel in warm climates characterized by increased greenhouse gas forcing.
Zhongshi Zhang, Xiangyu Li, Chuncheng Guo, Odd Helge Otterå, Kerim H. Nisancioglu, Ning Tan, Camille Contoux, Gilles Ramstein, Ran Feng, Bette L. Otto-Bliesner, Esther Brady, Deepak Chandan, W. Richard Peltier, Michiel L. J. Baatsen, Anna S. von der Heydt, Julia E. Weiffenbach, Christian Stepanek, Gerrit Lohmann, Qiong Zhang, Qiang Li, Mark A. Chandler, Linda E. Sohl, Alan M. Haywood, Stephen J. Hunter, Julia C. Tindall, Charles Williams, Daniel J. Lunt, Wing-Le Chan, and Ayako Abe-Ouchi
Clim. Past, 17, 529–543, https://doi.org/10.5194/cp-17-529-2021, https://doi.org/10.5194/cp-17-529-2021, 2021
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The Atlantic Meridional Overturning Circulation (AMOC) is an important topic in the Pliocene Model Intercomparison Project. Previous studies have suggested a much stronger AMOC during the Pliocene than today. However, our current multi-model intercomparison shows large model spreads and model–data discrepancies, which can not support the previous hypothesis. Our study shows good consistency with future projections of the AMOC.
Christian Stepanek, Eric Samakinwa, Gregor Knorr, and Gerrit Lohmann
Clim. Past, 16, 2275–2323, https://doi.org/10.5194/cp-16-2275-2020, https://doi.org/10.5194/cp-16-2275-2020, 2020
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Future climate is expected to be warmer than today. We study climate based on simulations of the mid-Pliocene (about 3 million years ago), which was a time of elevated temperatures, and discuss implications for the future. Our results are provided towards a comparison to both proxy evidence and output of other climate models. We simulate a mid-Pliocene climate that is both warmer and wetter than today. Some climate characteristics can be more directly transferred to the near future than others.
Eric Samakinwa, Christian Stepanek, and Gerrit Lohmann
Clim. Past, 16, 1643–1665, https://doi.org/10.5194/cp-16-1643-2020, https://doi.org/10.5194/cp-16-1643-2020, 2020
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Boundary conditions, forcing, and methodology for the two phases of PlioMIP differ considerably. We compare results from PlioMIP1 and PlioMIP2 simulations. We also carry out sensitivity experiments to infer the relative contribution of different boundary conditions to mid-Pliocene warmth. Our results show dominant effects of mid-Pliocene geography on the climate state and also that prescribing orbital forcing for different time slices within the mid-Pliocene could lead to pronounced variations.
Wing-Le Chan and Ayako Abe-Ouchi
Clim. Past, 16, 1523–1545, https://doi.org/10.5194/cp-16-1523-2020, https://doi.org/10.5194/cp-16-1523-2020, 2020
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We carry out several modelling experiments to investigate the climate of the mid-Piacenzian warm period (~ 3.205 Ma) when CO2 levels were similar to those of present day. The global surface air temperature is 3.1 °C higher compared to pre-industrial ones. Like previous experiments, the scale of warming suggested by proxy sea surface temperature (SST) data in the northern North Atlantic is not replicated. However, tropical Pacific SST shows good agreement with more recently published proxy data.
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.
Xiangyu Li, Chuncheng Guo, Zhongshi Zhang, Odd Helge Otterå, and Ran Zhang
Clim. Past, 16, 183–197, https://doi.org/10.5194/cp-16-183-2020, https://doi.org/10.5194/cp-16-183-2020, 2020
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Here we report the PlioMIP2 simulations by two versions of the Norwegian Earth System Model (NorESM) with updated boundary conditions derived from Pliocene Research, Interpretation and Synoptic Mapping version 4. The two NorESM versions both produce warmer and wetter Pliocene climate with deeper and stronger Atlantic meridional overturning circulation. Compared to PlioMIP1, PlioMIP2 simulates lower Pliocene warming with NorESM-L, likely due to the closure of seaways at northern high latitudes.
Gerlinde Jung and Matthias Prange
Clim. Past, 16, 161–181, https://doi.org/10.5194/cp-16-161-2020, https://doi.org/10.5194/cp-16-161-2020, 2020
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All major mountain ranges were uplifted during Earth's history. Previous work showed that African uplift might have influenced upper-ocean cooling in the Benguela region. But the surface ocean cooled also in other upwelling regions during the last 10 million years. We performed a set of model experiments altering topography in major mountain regions to explore the effects on atmosphere and ocean. The simulations show that mountain uplift is important for upper-ocean temperature evolution.
Ning Tan, Camille Contoux, Gilles Ramstein, Yong Sun, Christophe Dumas, Pierre Sepulchre, and Zhengtang Guo
Clim. Past, 16, 1–16, https://doi.org/10.5194/cp-16-1-2020, https://doi.org/10.5194/cp-16-1-2020, 2020
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To understand the warm climate during the late Pliocene (~3.205 Ma), modeling experiments with the new boundary conditions are launched and analyzed based on the Institut Pierre Simon Laplace (IPSL) atmosphere–ocean coupled general circulation model (AOGCM). Our results show that the warming in mid- to high latitudes enhanced due to the modifications of the land–sea mask and land–ice configuration. The pCO2 uncertainties within the records can produce asymmetrical warming patterns.
Stephen J. Hunter, Alan M. Haywood, Aisling M. Dolan, and Julia C. Tindall
Clim. Past, 15, 1691–1713, https://doi.org/10.5194/cp-15-1691-2019, https://doi.org/10.5194/cp-15-1691-2019, 2019
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In this paper, we model climate of the mid-Piacenzian warm period (mPWP; ~3 million years ago), a geological analogue for contemporary climate. Using the HadCM3 climate model, we show how changes in CO2 and geography contributed to mPWP climate. We find mPWP warmth focussed in the high latitudes, geography-driven precipitation changes, complex changes in sea surface temperature and intensified overturning in the North Atlantic (AMOC).
Brady Dortmans, William F. Langford, and Allan R. Willms
Clim. Past, 15, 493–520, https://doi.org/10.5194/cp-15-493-2019, https://doi.org/10.5194/cp-15-493-2019, 2019
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In geology and in paleoclimate science, most changes are caused by well-understood forces acting slowly over long periods of time. However, in highly nonlinear physical systems, mathematical bifurcation theory predicts that small changes in forcing can cause major changes in the system in a short period of time. This paper explores some sudden changes in the paleoclimate history of the Earth, where it appears that bifurcation theory gives a more satisfying explanation than uniformitarianism.
Hong Shen and Christopher J. Poulsen
Clim. Past, 15, 169–187, https://doi.org/10.5194/cp-15-169-2019, https://doi.org/10.5194/cp-15-169-2019, 2019
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The stable isotopic composition of water (δ18O) preserved in terrestrial sediments has been used to reconstruct surface elevations. The method is based on the observed decrease in δ18O with elevation, attributed to rainout during air mass ascent. We use a climate model to test the δ18O–elevation relationship during Tibetan–Himalayan uplift. We show that δ18O is a poor indicator of past elevation over most of the region, as processes other than rainout are important when elevations are lower.
Deepak Chandan and W. Richard Peltier
Clim. Past, 14, 825–856, https://doi.org/10.5194/cp-14-825-2018, https://doi.org/10.5194/cp-14-825-2018, 2018
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We infer the physical mechanisms by which the mid-Pliocene could have sustained a warm climate. We also provide a mid-Pliocene perspective on a range of climate sensitivities applicable on several timescales. Warming inferred on the basis of these sensitivity parameters is compared to forecasted levels of warming. This leads us to conclude that projections for 300–500 years into the future underestimate the potential for warming because they do not account for long-timescale feedback processes.
David K. Hutchinson, Agatha M. de Boer, Helen K. Coxall, Rodrigo Caballero, Johan Nilsson, and Michiel Baatsen
Clim. Past, 14, 789–810, https://doi.org/10.5194/cp-14-789-2018, https://doi.org/10.5194/cp-14-789-2018, 2018
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The Eocene--Oligocene transition was a major cooling event 34 million years ago. Climate model studies of this transition have used low ocean resolution or topography that roughly approximates the time period. We present a new climate model simulation of the late Eocene, with higher ocean resolution and topography which is accurately designed for this time period. These features improve the ocean circulation and gateways which are thought to be important for this climate transition.
Baohuang Su, Dabang Jiang, Ran Zhang, Pierre Sepulchre, and Gilles Ramstein
Clim. Past, 14, 751–762, https://doi.org/10.5194/cp-14-751-2018, https://doi.org/10.5194/cp-14-751-2018, 2018
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The present numerical experiments undertaken by a coupled atmosphere–ocean model indicate that the uplift of the Tibetan Plateau alone could have been a potential driver for the reorganization of Pacific and Atlantic meridional overturning circulations between the late Eocene and early Oligocene. In other words, the Tibetan Plateau could play an important role in maintaining the current large-scale overturning circulation in the Atlantic and Pacific.
John S. Keery, Philip B. Holden, and Neil R. Edwards
Clim. Past, 14, 215–238, https://doi.org/10.5194/cp-14-215-2018, https://doi.org/10.5194/cp-14-215-2018, 2018
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In the Eocene (~ 55 million years ago), the Earth had high levels of atmospheric CO2, so studies of the Eocene can provide insights into the likely effects of present-day fossil fuel burning. We ran a low-resolution but very fast climate model with 50 combinations of CO2 and orbital parameters, and an Eocene layout of the oceans and continents. Climatic effects of CO2 are dominant but precession and obliquity strongly influence monsoon rainfall and ocean–land temperature contrasts, respectively.
Lennert B. Stap, Roderik S. W. van de Wal, Bas de Boer, Richard Bintanja, and Lucas J. Lourens
Clim. Past, 13, 1243–1257, https://doi.org/10.5194/cp-13-1243-2017, https://doi.org/10.5194/cp-13-1243-2017, 2017
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We show the results of transient simulations with a coupled climate–ice sheet model over the past 38 million years. The CO2 forcing of the model is inversely obtained from a benthic δ18O stack. These simulations enable us to study the influence of ice sheet variability on climate change on long timescales. We find that ice sheet–climate interaction strongly enhances Earth system sensitivity and polar amplification.
Deepak Chandan and W. Richard Peltier
Clim. Past, 13, 919–942, https://doi.org/10.5194/cp-13-919-2017, https://doi.org/10.5194/cp-13-919-2017, 2017
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This paper discusses the climate of the mid-Pliocene warm period (~ 3.3–3 Mya) obtained using coupled climate simulations at CMIP5 resolution with the CCSM4 model and the boundary conditions (BCs) prescribed for the PlioMIP2 program. It is found that climate simulations performed with these BCs capture the warming patterns inferred from proxy data much better than what was possible with the BCs for the original PlioMIP program.
Shawn Corvec and Christopher G. Fletcher
Clim. Past, 13, 135–147, https://doi.org/10.5194/cp-13-135-2017, https://doi.org/10.5194/cp-13-135-2017, 2017
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The mid-Pliocene warm period is sometimes thought of as being a climate that could closely resemble the climate in the near-term due to anthropogenic climate change. Here we examine the tropical atmospheric circulation as modeled by PlioMIP (the Pliocene Model Intercomparison Project). We find that there are many similarities and some important differences to projections of future climate, with the pattern of sea surface temperature (SST) warming being a key factor in explaining the differences.
Michiel Baatsen, Douwe J. J. van Hinsbergen, Anna S. von der Heydt, Henk A. Dijkstra, Appy Sluijs, Hemmo A. Abels, and Peter K. Bijl
Clim. Past, 12, 1635–1644, https://doi.org/10.5194/cp-12-1635-2016, https://doi.org/10.5194/cp-12-1635-2016, 2016
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One of the major difficulties in modelling palaeoclimate is constricting the boundary conditions, causing significant discrepancies between different studies. Here, a new method is presented to automate much of the process of generating the necessary geographical reconstructions. The latter can be made using various rotational frameworks and topography/bathymetry input, allowing for easy inter-comparisons and the incorporation of the latest insights from geoscientific research.
Willem P. Sijp, Anna S. von der Heydt, and Peter K. Bijl
Clim. Past, 12, 807–817, https://doi.org/10.5194/cp-12-807-2016, https://doi.org/10.5194/cp-12-807-2016, 2016
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The timing and role in ocean circulation and climate of the opening of Southern Ocean gateways is as yet elusive. Here, we present the first model results specific to the early-to-middle Eocene where, in agreement with the field evidence, a southerly shallow opening of the Tasman Gateway does indeed cause a westward flow across the Tasman Gateway, in agreement with recent micropalaeontological studies.
Fergus W. Howell, Alan M. Haywood, Bette L. Otto-Bliesner, Fran Bragg, Wing-Le Chan, Mark A. Chandler, Camille Contoux, Youichi Kamae, Ayako Abe-Ouchi, Nan A. Rosenbloom, Christian Stepanek, and Zhongshi Zhang
Clim. Past, 12, 749–767, https://doi.org/10.5194/cp-12-749-2016, https://doi.org/10.5194/cp-12-749-2016, 2016
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Simulations of pre-industrial and mid-Pliocene Arctic sea ice by eight GCMs are analysed. Ensemble variability in sea ice extent is greater in the mid-Pliocene summer, when half of the models simulate sea-ice-free conditions. Weaker correlations are seen between sea ice extent and temperatures in the pre-industrial era compared to the mid-Pliocene. The need for more comprehensive sea ice proxy data is highlighted, in order to better compare model performances.
Alan M. Haywood, Harry J. Dowsett, Aisling M. Dolan, David Rowley, Ayako Abe-Ouchi, Bette Otto-Bliesner, Mark A. Chandler, Stephen J. Hunter, Daniel J. Lunt, Matthew Pound, and Ulrich Salzmann
Clim. Past, 12, 663–675, https://doi.org/10.5194/cp-12-663-2016, https://doi.org/10.5194/cp-12-663-2016, 2016
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Our paper presents the experimental design for the second phase of the Pliocene Model Intercomparison Project (PlioMIP). We outline the way in which climate models should be set up in order to study the Pliocene – a period of global warmth in Earth's history which is relevant for our understanding of future climate change. By conducting a model intercomparison we hope to understand the uncertainty associated with model predictions of a warmer climate.
J. H. Koh and C. M. Brierley
Clim. Past, 11, 1433–1451, https://doi.org/10.5194/cp-11-1433-2015, https://doi.org/10.5194/cp-11-1433-2015, 2015
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Here we diagnose simulated changes in large-scale climate variables associated with the formation of tropical cyclones (i.e. hurricanes and typhoons). The cumulative potential for storm formation is pretty constant, despite the climate changes between the Last Glacial Maximum and the warm Pliocene. There are, however, coherent shifts in the relative strength of the storm regions. Little connection appears between the past behaviour in the five models studied and their future projections.
A. Marzocchi, D. J. Lunt, R. Flecker, C. D. Bradshaw, A. Farnsworth, and F. J. Hilgen
Clim. Past, 11, 1271–1295, https://doi.org/10.5194/cp-11-1271-2015, https://doi.org/10.5194/cp-11-1271-2015, 2015
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This paper investigates the climatic response to orbital forcing through the analysis of an ensemble of simulations covering a late Miocene precession cycle. Including orbital variability in our model–data comparison reduces the mismatch between the proxy record and model output. Our results indicate that ignoring orbital variability could lead to miscorrelations in proxy reconstructions. The North African summer monsoon's sensitivity is high to orbits, moderate to paleogeography and low to CO2.
C. M. Brierley
Clim. Past, 11, 605–618, https://doi.org/10.5194/cp-11-605-2015, https://doi.org/10.5194/cp-11-605-2015, 2015
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Previously, model ensembles have shown little consensus in the response of the El Niño–Southern Oscillation (ENSO) to imposed forcings – either for the past or future. The recent coordinated experiment on the warm Pliocene (~3 million years ago) shows surprising agreement that there was a robustly weaker ENSO with a shift to lower frequencies. Suggested physical mechanisms cannot explain this coherent signal, and it warrants further investigation.
S. J. Koenig, A. M. Dolan, B. de Boer, E. J. Stone, D. J. Hill, R. M. DeConto, A. Abe-Ouchi, D. J. Lunt, D. Pollard, A. Quiquet, F. Saito, J. Savage, and R. van de Wal
Clim. Past, 11, 369–381, https://doi.org/10.5194/cp-11-369-2015, https://doi.org/10.5194/cp-11-369-2015, 2015
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The paper assess the Greenland Ice Sheet’s sensitivity to a warm period in the past, a time when atmospheric CO2 concentrations were comparable to current levels. We quantify ice sheet volume and locations in Greenland and find that the ice sheets are less sensitive to differences in ice sheet model configurations than to changes in imposed climate forcing. We conclude that Pliocene ice was most likely to be limited to highest elevations in eastern and southern Greenland.
A. M. Dolan, S. J. Hunter, D. J. Hill, A. M. Haywood, S. J. Koenig, B. L. Otto-Bliesner, A. Abe-Ouchi, F. Bragg, W.-L. Chan, M. A. Chandler, C. Contoux, A. Jost, Y. Kamae, G. Lohmann, D. J. Lunt, G. Ramstein, N. A. Rosenbloom, L. Sohl, C. Stepanek, H. Ueda, Q. Yan, and Z. Zhang
Clim. Past, 11, 403–424, https://doi.org/10.5194/cp-11-403-2015, https://doi.org/10.5194/cp-11-403-2015, 2015
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Climate and ice sheet models are often used to predict the nature of ice sheets in Earth history. It is important to understand whether such predictions are consistent among different models, especially in warm periods of relevance to the future. We use input from 15 different climate models to run one ice sheet model and compare the predictions over Greenland. We find that there are large differences between the predicted ice sheets for the warm Pliocene (c. 3 million years ago).
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
R. F. Ivanovic, P. J. Valdes, R. Flecker, and M. Gutjahr
Clim. Past, 10, 607–622, https://doi.org/10.5194/cp-10-607-2014, https://doi.org/10.5194/cp-10-607-2014, 2014
E. Gasson, D. J. Lunt, R. DeConto, A. Goldner, M. Heinemann, M. Huber, A. N. LeGrande, D. Pollard, N. Sagoo, M. Siddall, A. Winguth, and P. J. Valdes
Clim. Past, 10, 451–466, https://doi.org/10.5194/cp-10-451-2014, https://doi.org/10.5194/cp-10-451-2014, 2014
C. A. Loptson, D. J. Lunt, and J. E. Francis
Clim. Past, 10, 419–436, https://doi.org/10.5194/cp-10-419-2014, https://doi.org/10.5194/cp-10-419-2014, 2014
D. J. Hill, A. M. Haywood, D. J. Lunt, S. J. Hunter, F. J. Bragg, C. Contoux, C. Stepanek, L. Sohl, N. A. Rosenbloom, W.-L. Chan, Y. Kamae, Z. Zhang, A. Abe-Ouchi, M. A. Chandler, A. Jost, G. Lohmann, B. L. Otto-Bliesner, G. Ramstein, and H. Ueda
Clim. Past, 10, 79–90, https://doi.org/10.5194/cp-10-79-2014, https://doi.org/10.5194/cp-10-79-2014, 2014
N. Hamon, P. Sepulchre, V. Lefebvre, and G. Ramstein
Clim. Past, 9, 2687–2702, https://doi.org/10.5194/cp-9-2687-2013, https://doi.org/10.5194/cp-9-2687-2013, 2013
R. Zhang, Q. Yan, Z. S. Zhang, D. Jiang, B. L. Otto-Bliesner, A. M. Haywood, D. J. Hill, A. M. Dolan, C. Stepanek, G. Lohmann, C. Contoux, F. Bragg, W.-L. Chan, M. A. Chandler, A. Jost, Y. Kamae, A. Abe-Ouchi, G. Ramstein, N. A. Rosenbloom, L. Sohl, and H. Ueda
Clim. Past, 9, 2085–2099, https://doi.org/10.5194/cp-9-2085-2013, https://doi.org/10.5194/cp-9-2085-2013, 2013
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