Articles | Volume 14, issue 2
https://doi.org/10.5194/cp-14-239-2018
© Author(s) 2018. 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-14-239-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
02 Mar 2018
Research article |
| 02 Mar 2018
Response of the carbon cycle in an intermediate complexity model to the different climate configurations of the last nine interglacials
Nathaelle Bouttes
CORRESPONDING AUTHOR
Univ. Bordeaux, EPOC, UMR 5805, 33615 Pessac, France
Didier Swingedouw
Univ. Bordeaux, EPOC, UMR 5805, 33615 Pessac, France
Didier M. Roche
Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
Earth and Climate Cluster, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
Maria F. Sanchez-Goni
Univ. Bordeaux, EPOC, UMR 5805, 33615 Pessac, France
EPHE, PSL Research University, 33615 Pessac, France
Xavier Crosta
Univ. Bordeaux, EPOC, UMR 5805, 33615 Pessac, France
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Isabel A. Dove, Ian W. Bishop, Xavier Crosta, Natascha Riedinger, R. Patrick Kelly, and Rebecca S. Robinson
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Ryan A. Green, Laurie Menviel, Katrin J. Meissner, Xavier Crosta, Deepak Chandan, Gerrit Lohmann, W. Richard Peltier, Xiaoxu Shi, and Jiang Zhu
Clim. Past, 18, 845–862, https://doi.org/10.5194/cp-18-845-2022, https://doi.org/10.5194/cp-18-845-2022, 2022
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Climate models are used to predict future climate changes and as such, it is important to assess their performance in simulating past climate changes. We analyze seasonal sea-ice cover over the Southern Ocean simulated from numerical PMIP3, PMIP4 and LOVECLIM simulations during the Last Glacial Maximum (LGM). Comparing these simulations to proxy data, we provide improved estimates of LGM seasonal sea-ice cover. Our estimate of summer sea-ice extent is 20 %–30 % larger than previous estimates.
Jacob Jones, Karen E. Kohfeld, Helen Bostock, Xavier Crosta, Melanie Liston, Gavin Dunbar, Zanna Chase, Amy Leventer, Harris Anderson, and Geraldine Jacobsen
Clim. Past, 18, 465–483, https://doi.org/10.5194/cp-18-465-2022, https://doi.org/10.5194/cp-18-465-2022, 2022
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We provide new winter sea ice and summer sea surface temperature estimates for marine core TAN1302-96 (59° S, 157° E) in the Southern Ocean. We find that sea ice was not consolidated over the core site until ~65 ka and therefore believe that sea ice may not have been a major contributor to early glacial CO2 drawdown. Sea ice does appear to have coincided with Antarctic Intermediate Water production and subduction, suggesting it may have influenced intermediate ocean circulation changes.
Matthew Chadwick, Claire S. Allen, Louise C. Sime, Xavier Crosta, and Claus-Dieter Hillenbrand
Clim. Past, 18, 129–146, https://doi.org/10.5194/cp-18-129-2022, https://doi.org/10.5194/cp-18-129-2022, 2022
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Algae preserved in marine sediments have allowed us to reconstruct how much winter sea ice was present around Antarctica during a past time period (130 000 years ago) when the climate was warmer than today. The patterns of sea-ice increase and decrease vary between different parts of the Southern Ocean. The Pacific sector has a largely stable sea-ice extent, whereas the amount of sea ice in the Atlantic sector is much more variable with bigger decreases and increases than other regions.
Kelly-Anne Lawler, Giuseppe Cortese, Matthieu Civel-Mazens, Helen Bostock, Xavier Crosta, Amy Leventer, Vikki Lowe, John Rogers, and Leanne K. Armand
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The Gulf Stream and the Kuroshio are major currents of the North Atlantic and North Pacific, respectively. They transport warm water northward and are key components of the Earth climate system. For this study, we looked at how they affect the sea level of the coasts of Japan, the USA and Canada. We found that the inshore sea level
co-varies with the north-to-south shifts of the Gulf Stream and Kuroshio. In the paper, we discuss the physical mechanisms that could explain the agreement.
Aurélien Quiquet, Didier M. Roche, Christophe Dumas, Nathaëlle Bouttes, and Fanny Lhardy
Clim. Past, 17, 2179–2199, https://doi.org/10.5194/cp-17-2179-2021, https://doi.org/10.5194/cp-17-2179-2021, 2021
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In this paper we discuss results obtained with a set of coupled ice-sheet–climate model experiments for the last 26 kyrs. The model displays a large sensitivity of the oceanic circulation to the amount of the freshwater flux resulting from ice sheet melting. Ice sheet geometry changes alone are not enough to lead to abrupt climate events, and rapid warming at high latitudes is here only reported during abrupt oceanic circulation recoveries that occurred when accounting for freshwater flux.
Kate E. Ashley, Xavier Crosta, Johan Etourneau, Philippine Campagne, Harry Gilchrist, Uthmaan Ibraheem, Sarah E. Greene, Sabine Schmidt, Yvette Eley, Guillaume Massé, and James Bendle
Biogeosciences, 18, 5555–5571, https://doi.org/10.5194/bg-18-5555-2021, https://doi.org/10.5194/bg-18-5555-2021, 2021
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We explore the potential for the use of carbon isotopes of algal fatty acid as a new proxy for past primary productivity in Antarctic coastal zones. Coastal polynyas are hotspots of primary productivity and are known to draw down CO2 from the atmosphere. Reconstructions of past productivity changes could provide a baseline for the role of these areas as sinks for atmospheric CO2.
Fanny Lhardy, Nathaëlle Bouttes, Didier M. Roche, Xavier Crosta, Claire Waelbroeck, and Didier Paillard
Clim. Past, 17, 1139–1159, https://doi.org/10.5194/cp-17-1139-2021, https://doi.org/10.5194/cp-17-1139-2021, 2021
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Climate models struggle to simulate a LGM ocean circulation in agreement with paleotracer data. Using a set of simulations, we test the impact of boundary conditions and other modelling choices. Model–data comparisons of sea-surface temperatures and sea-ice cover support an overall cold Southern Ocean, with implications on the AMOC strength. Changes in implemented boundary conditions are not sufficient to simulate a shallower AMOC; other mechanisms to better represent convection are required.
Masa Kageyama, Sandy P. Harrison, Marie-L. Kapsch, Marcus Lofverstrom, Juan M. Lora, Uwe Mikolajewicz, Sam Sherriff-Tadano, Tristan Vadsaria, Ayako Abe-Ouchi, Nathaelle Bouttes, Deepak Chandan, Lauren J. Gregoire, Ruza F. Ivanovic, Kenji Izumi, Allegra N. LeGrande, Fanny Lhardy, Gerrit Lohmann, Polina A. Morozova, Rumi Ohgaito, André Paul, W. Richard Peltier, Christopher J. Poulsen, Aurélien Quiquet, Didier M. Roche, Xiaoxu Shi, Jessica E. Tierney, Paul J. Valdes, Evgeny Volodin, and Jiang Zhu
Clim. Past, 17, 1065–1089, https://doi.org/10.5194/cp-17-1065-2021, https://doi.org/10.5194/cp-17-1065-2021, 2021
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The Last Glacial Maximum (LGM; ~21 000 years ago) is a major focus for evaluating how well climate models simulate climate changes as large as those expected in the future. Here, we compare the latest climate model (CMIP6-PMIP4) to the previous one (CMIP5-PMIP3) and to reconstructions. Large-scale climate features (e.g. land–sea contrast, polar amplification) are well captured by all models, while regional changes (e.g. winter extratropical cooling, precipitations) are still poorly represented.
Kate E. Ashley, Robert McKay, Johan Etourneau, Francisco J. Jimenez-Espejo, Alan Condron, Anna Albot, Xavier Crosta, Christina Riesselman, Osamu Seki, Guillaume Massé, Nicholas R. Golledge, Edward Gasson, Daniel P. Lowry, Nicholas E. Barrand, Katelyn Johnson, Nancy Bertler, Carlota Escutia, Robert Dunbar, and James A. Bendle
Clim. Past, 17, 1–19, https://doi.org/10.5194/cp-17-1-2021, https://doi.org/10.5194/cp-17-1-2021, 2021
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We present a multi-proxy record of Holocene glacial meltwater input, sediment transport, and sea-ice variability off East Antarctica. Our record shows that a rapid Antarctic sea-ice increase during the mid-Holocene (~ 4.5 ka) occurred against a backdrop of increasing glacial meltwater input and gradual climate warming. We suggest that mid-Holocene ice shelf cavity expansion led to cooling of surface waters and sea-ice growth, which slowed basal ice shelf melting.
Ramdane Alkama, Patrick C. Taylor, Lorea Garcia-San Martin, Herve Douville, Gregory Duveiller, Giovanni Forzieri, Didier Swingedouw, and Alessandro Cescatti
The Cryosphere, 14, 2673–2686, https://doi.org/10.5194/tc-14-2673-2020, https://doi.org/10.5194/tc-14-2673-2020, 2020
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The amount of solar energy absorbed by Earth is believed to strongly depend on clouds. Here, we investigate this relationship using satellite data and 32 climate models, showing that this relationship holds everywhere except over polar seas, where an increased reflection by clouds corresponds to an increase in absorbed solar radiation at the surface. This interplay between clouds and sea ice reduces by half the increase of net radiation at the surface that follows the sea ice retreat.
Lisa Claire Orme, Xavier Crosta, Arto Miettinen, Dmitry V. Divine, Katrine Husum, Elisabeth Isaksson, Lukas Wacker, Rahul Mohan, Olivier Ther, and Minoru Ikehara
Clim. Past, 16, 1451–1467, https://doi.org/10.5194/cp-16-1451-2020, https://doi.org/10.5194/cp-16-1451-2020, 2020
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A record of past sea temperature in the Indian sector of the Southern Ocean, spanning the last 14 200 years, has been developed by analysis of fossil diatoms in marine sediment. During the late deglaciation the reconstructed temperature changes were highly similar to those over Antarctica, most likely due to a reorganisation of global ocean and atmospheric circulation. During the last 11 600 years temperatures gradually cooled and became increasingly variable.
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.
Brett Metcalfe, Bryan C. Lougheed, Claire Waelbroeck, and Didier M. Roche
Clim. Past, 16, 885–910, https://doi.org/10.5194/cp-16-885-2020, https://doi.org/10.5194/cp-16-885-2020, 2020
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Planktonic foraminifera construct a shell that, post mortem, settles to the seafloor, prior to collection by Palaeoclimatologists for use as proxies. Such organisms in life are sensitive to the ambient conditions (e.g. temperature, salinity), which therefore means our proxies maybe skewed toward the ecology of organisms. Using a proxy system model, Foraminifera as Modelled Entities (FAME), we assess the potential of extracting ENSO signal from tropical Pacific planktonic foraminifera.
Lise Missiaen, Nathaelle Bouttes, Didier M. Roche, Jean-Claude Dutay, Aurélien Quiquet, Claire Waelbroeck, Sylvain Pichat, and Jean-Yves Peterschmitt
Clim. Past, 16, 867–883, https://doi.org/10.5194/cp-16-867-2020, https://doi.org/10.5194/cp-16-867-2020, 2020
Simon Michel, Didier Swingedouw, Marie Chavent, Pablo Ortega, Juliette Mignot, and Myriam Khodri
Geosci. Model Dev., 13, 841–858, https://doi.org/10.5194/gmd-13-841-2020, https://doi.org/10.5194/gmd-13-841-2020, 2020
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Natural archives such as sediments, ice, tree rings or speleothems provide indirect observations of past climate at local and regional scales. In this paper, we provide a computational device to properly make evaluated reconstructions of climate indices using these paleo-data. It provides optimizing cross-validation algorithms and four regression methods that are applied to the reconstruction of the North Atlantic Oscillation index and compared in this study.
Pierre Sabatier, Marie Nicolle, Christine Piot, Christophe Colin, Maxime Debret, Didier Swingedouw, Yves Perrette, Marie-Charlotte Bellingery, Benjamin Chazeau, Anne-Lise Develle, Maxime Leblanc, Charlotte Skonieczny, Yoann Copard, Jean-Louis Reyss, Emmanuel Malet, Isabelle Jouffroy-Bapicot, Maëlle Kelner, Jérôme Poulenard, Julien Didier, Fabien Arnaud, and Boris Vannière
Clim. Past, 16, 283–298, https://doi.org/10.5194/cp-16-283-2020, https://doi.org/10.5194/cp-16-283-2020, 2020
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High-resolution multiproxy analysis of sediment core from a high-elevation lake on Corsica allows us to reconstruct past African dust inputs to the western Mediterranean area over the last 3 millennia. Millennial variations of Saharan dust input have been correlated with the long-term southward migration of the Intertropical Convergence Zone, while short-term variations were associated with the North Atlantic Oscillation and total solar irradiance after and before 1070 cal BP, respectively.
Aurélien Quiquet, Christophe Dumas, Catherine Ritz, Vincent Peyaud, and Didier M. Roche
Geosci. Model Dev., 11, 5003–5025, https://doi.org/10.5194/gmd-11-5003-2018, https://doi.org/10.5194/gmd-11-5003-2018, 2018
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This paper presents the GRISLI (Grenoble ice sheet and land ice) model in its newest revision. We present the recent model improvements from its original version (Ritz et al., 2001), together with a discussion of the model performance in reproducing the present-day Antarctic ice sheet geometry and the grounding line advances and retreats during the last 400 000 years. We show that GRISLI is a computationally cheap model, able to reproduce the large-scale behaviour of ice sheets.
Didier M. Roche, Claire Waelbroeck, Brett Metcalfe, and Thibaut Caley
Geosci. Model Dev., 11, 3587–3603, https://doi.org/10.5194/gmd-11-3587-2018, https://doi.org/10.5194/gmd-11-3587-2018, 2018
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The oxygen-18 signal recorded in fossil planktonic foraminifers has been used for over 50 years in many geoscience applications. However, different planktonic foraminifer species from the same sediment core generally yield distinct oxygen-18 signals, as a consequence of their specific living habitat in the water column and along the year. To explicitly take into account this variability for five common planktonic species, we developed the portable module FAME (Foraminifers As Modeled Entities).
Masa Kageyama, Pascale Braconnot, Sandy P. Harrison, Alan M. Haywood, Johann H. Jungclaus, Bette L. Otto-Bliesner, Jean-Yves Peterschmitt, Ayako Abe-Ouchi, Samuel Albani, Patrick J. Bartlein, Chris Brierley, Michel Crucifix, Aisling Dolan, Laura Fernandez-Donado, Hubertus Fischer, Peter O. Hopcroft, Ruza F. Ivanovic, Fabrice Lambert, Daniel J. Lunt, Natalie M. Mahowald, W. Richard Peltier, Steven J. Phipps, Didier M. Roche, Gavin A. Schmidt, Lev Tarasov, Paul J. Valdes, Qiong Zhang, and Tianjun Zhou
Geosci. Model Dev., 11, 1033–1057, https://doi.org/10.5194/gmd-11-1033-2018, https://doi.org/10.5194/gmd-11-1033-2018, 2018
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The Paleoclimate Modelling Intercomparison Project (PMIP) takes advantage of the existence of past climate states radically different from the recent past to test climate models used for climate projections and to better understand these climates. This paper describes the PMIP contribution to CMIP6 (Coupled Model Intercomparison Project, 6th phase) and possible analyses based on PMIP results, as well as on other CMIP6 projects.
Aurélien Quiquet, Didier M. Roche, Christophe Dumas, and Didier Paillard
Geosci. Model Dev., 11, 453–466, https://doi.org/10.5194/gmd-11-453-2018, https://doi.org/10.5194/gmd-11-453-2018, 2018
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Earth system models of intermediate complexity generally have a simplified model physics and a coarse model resolution. In this work we present the inclusion of an online dynamical downscaling of temperature and precipitation in such a model. This downscaling explicitly takes into account sub-grid topography. With this new model functionality we are able to simulate temperature and precipitation on a 40 km grid for the whole Northern Hemisphere from the native model resolution.
Masa Kageyama, Samuel Albani, Pascale Braconnot, Sandy P. Harrison, Peter O. Hopcroft, Ruza F. Ivanovic, Fabrice Lambert, Olivier Marti, W. Richard Peltier, Jean-Yves Peterschmitt, Didier M. Roche, Lev Tarasov, Xu Zhang, Esther C. Brady, Alan M. Haywood, Allegra N. LeGrande, Daniel J. Lunt, Natalie M. Mahowald, Uwe Mikolajewicz, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, Hans Renssen, Robert A. Tomas, Qiong Zhang, Ayako Abe-Ouchi, Patrick J. Bartlein, Jian Cao, Qiang Li, Gerrit Lohmann, Rumi Ohgaito, Xiaoxu Shi, Evgeny Volodin, Kohei Yoshida, Xiao Zhang, and Weipeng Zheng
Geosci. Model Dev., 10, 4035–4055, https://doi.org/10.5194/gmd-10-4035-2017, https://doi.org/10.5194/gmd-10-4035-2017, 2017
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The Last Glacial Maximum (LGM, 21000 years ago) is an interval when global ice volume was at a maximum, eustatic sea level close to a minimum, greenhouse gas concentrations were lower, atmospheric aerosol loadings were higher than today, and vegetation and land-surface characteristics were different from today. This paper describes the implementation of the LGM numerical experiment for the PMIP4-CMIP6 modelling intercomparison projects and the associated sensitivity experiments.
María Fernanda Sánchez Goñi, Stéphanie Desprat, Anne-Laure Daniau, Frank C. Bassinot, Josué M. Polanco-Martínez, Sandy P. Harrison, Judy R. M. Allen, R. Scott Anderson, Hermann Behling, Raymonde Bonnefille, Francesc Burjachs, José S. Carrión, Rachid Cheddadi, James S. Clark, Nathalie Combourieu-Nebout, Colin. J. Courtney Mustaphi, Georg H. Debusk, Lydie M. Dupont, Jemma M. Finch, William J. Fletcher, Marco Giardini, Catalina González, William D. Gosling, Laurie D. Grigg, Eric C. Grimm, Ryoma Hayashi, Karin Helmens, Linda E. Heusser, Trevor Hill, Geoffrey Hope, Brian Huntley, Yaeko Igarashi, Tomohisa Irino, Bonnie Jacobs, Gonzalo Jiménez-Moreno, Sayuri Kawai, A. Peter Kershaw, Fujio Kumon, Ian T. Lawson, Marie-Pierre Ledru, Anne-Marie Lézine, Ping Mei Liew, Donatella Magri, Robert Marchant, Vasiliki Margari, Francis E. Mayle, G. Merna McKenzie, Patrick Moss, Stefanie Müller, Ulrich C. Müller, Filipa Naughton, Rewi M. Newnham, Tadamichi Oba, Ramón Pérez-Obiol, Roberta Pini, Cesare Ravazzi, Katy H. Roucoux, Stephen M. Rucina, Louis Scott, Hikaru Takahara, Polichronis C. Tzedakis, Dunia H. Urrego, Bas van Geel, B. Guido Valencia, Marcus J. Vandergoes, Annie Vincens, Cathy L. Whitlock, Debra A. Willard, and Masanobu Yamamoto
Earth Syst. Sci. Data, 9, 679–695, https://doi.org/10.5194/essd-9-679-2017, https://doi.org/10.5194/essd-9-679-2017, 2017
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The ACER (Abrupt Climate Changes and Environmental Responses) global database includes 93 pollen records from the last glacial period (73–15 ka) plotted against a common chronology; 32 also provide charcoal records. The database allows for the reconstruction of the regional expression, vegetation and fire of past abrupt climate changes that are comparable to those expected in the 21st century. This work is a major contribution to understanding the processes behind rapid climate change.
Mélanie Wary, Frédérique Eynaud, Didier Swingedouw, Valérie Masson-Delmotte, Jens Matthiessen, Catherine Kissel, Jena Zumaque, Linda Rossignol, and Jean Jouzel
Clim. Past, 13, 729–739, https://doi.org/10.5194/cp-13-729-2017, https://doi.org/10.5194/cp-13-729-2017, 2017
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The last glacial period was punctuated by abrupt climatic variations, whose cold atmospheric phases have been commonly associated with cold sea-surface temperatures and expansion of sea ice in the North Atlantic and adjacent seas. Here we provide direct evidence of a regional paradoxical see-saw pattern: cold Greenland and North Atlantic phases coincide with warmer sea-surface conditions and shorter seasonal sea-ice cover durations in the Norwegian Sea as compared to warm phases.
Jonathan M. Gregory, Nathaelle Bouttes, Stephen M. Griffies, Helmuth Haak, William J. Hurlin, Johann Jungclaus, Maxwell Kelley, Warren G. Lee, John Marshall, Anastasia Romanou, Oleg A. Saenko, Detlef Stammer, and Michael Winton
Geosci. Model Dev., 9, 3993–4017, https://doi.org/10.5194/gmd-9-3993-2016, https://doi.org/10.5194/gmd-9-3993-2016, 2016
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As a consequence of greenhouse gas emissions, changes in ocean temperature, salinity, circulation and sea level are expected in coming decades. Among the models used for climate projections for the 21st century, there is a large spread in projections of these effects. The Flux-Anomaly-Forced Model Intercomparison Project (FAFMIP) aims to investigate and explain this spread by prescribing a common set of changes in the input of heat, water and wind stress to the ocean in the participating models.
Pierre Burckel, Claire Waelbroeck, Yiming Luo, Didier M. Roche, Sylvain Pichat, Samuel L. Jaccard, Jeanne Gherardi, Aline Govin, Jörg Lippold, and François Thil
Clim. Past, 12, 2061–2075, https://doi.org/10.5194/cp-12-2061-2016, https://doi.org/10.5194/cp-12-2061-2016, 2016
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In this paper, we compare new and published Atlantic sedimentary Pa/Th data with Pa/Th simulated using stream functions generated under various climatic conditions. We show that during Greenland interstadials of the 20–50 ka period, the Atlantic meridional overturning circulation was very different from that of the Holocene. Moreover, southern-sourced waters dominated the Atlantic during Heinrich stadial 2, a slow northern-sourced water mass flowing above 2500 m in the North Atlantic.
Timothé Bolliet, Patrick Brockmann, Valérie Masson-Delmotte, Franck Bassinot, Valérie Daux, Dominique Genty, Amaelle Landais, Marlène Lavrieux, Elisabeth Michel, Pablo Ortega, Camille Risi, Didier M. Roche, Françoise Vimeux, and Claire Waelbroeck
Clim. Past, 12, 1693–1719, https://doi.org/10.5194/cp-12-1693-2016, https://doi.org/10.5194/cp-12-1693-2016, 2016
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This paper presents a new database of past climate proxies which aims to facilitate the distribution of data by using a user-friendly interface. Available data from the last 40 years are often fragmented, with lots of different formats, and online libraries are sometimes nonintuitive. We thus built a new dynamic web portal for data browsing, visualizing, and batch downloading of hundreds of datasets presenting a homogeneous format.
Ruza F. Ivanovic, Lauren J. Gregoire, Masa Kageyama, Didier M. Roche, Paul J. Valdes, Andrea Burke, Rosemarie Drummond, W. Richard Peltier, and Lev Tarasov
Geosci. Model Dev., 9, 2563–2587, https://doi.org/10.5194/gmd-9-2563-2016, https://doi.org/10.5194/gmd-9-2563-2016, 2016
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This manuscript presents the experiment design for the PMIP4 Last Deglaciation Core experiment: a transient simulation of the last deglaciation, 21–9 ka. Specified model boundary conditions include time-varying orbital parameters, greenhouse gases, ice sheets, ice meltwater fluxes and other geographical changes (provided for 26–0 ka). The context of the experiment and the choices for the boundary conditions are explained, along with the future direction of the working group.
Philippine Campagne, Xavier Crosta, Sabine Schmidt, Marie Noëlle Houssais, Olivier Ther, and Guillaume Massé
Biogeosciences, 13, 4205–4218, https://doi.org/10.5194/bg-13-4205-2016, https://doi.org/10.5194/bg-13-4205-2016, 2016
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Diatoms and biomarkers have been recently used for palaeoclimate reconstructions in the Southern Ocean. Few sediment-based ecological studies have investigated their relationships with environmental conditions. Here, we compare high-resolution sedimentary records with meteorological data to study relationships between our proxies and recent atmospheric and sea surface changes. Our results indicate that coupled wind pattern and sea surface variability act as the proximal forcing at that scale.
Marianne Bügelmayer-Blaschek, Didier M. Roche, Hans Renssen, and Claire Waelbroeck
Clim. Past Discuss., https://doi.org/10.5194/cp-2016-31, https://doi.org/10.5194/cp-2016-31, 2016
Revised manuscript has not been submitted
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Using the global isotope-enabled climate – iceberg model iLOVECLIM we performed three experiments to investigate the mechanisms behind the simulated δ18Ocalcite pattern applying a Heinrich event like iceberg forcing. Our model results display two main patterns in the δ18Ocalcite signal. First, we find regions that display almost no response in δ18Ocalcite and second, regions where the δ18Ocalcite pattern closely follows the δ18Oseawater signal.
M. Bügelmayer, D. M. Roche, and H. Renssen
Geosci. Model Dev., 8, 2139–2151, https://doi.org/10.5194/gmd-8-2139-2015, https://doi.org/10.5194/gmd-8-2139-2015, 2015
N. Bouttes, D. M. Roche, V. Mariotti, and L. Bopp
Geosci. Model Dev., 8, 1563–1576, https://doi.org/10.5194/gmd-8-1563-2015, https://doi.org/10.5194/gmd-8-1563-2015, 2015
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We describe the development of a relatively simple climate model to include a model of the carbon cycle in the ocean. The carbon cycle consists of the exchange of carbon between the atmosphere, land vegetation and ocean. In the ocean, carbon exists in organic form, such as plankton which grows and dies, and inorganic forms, such as dissolved CO2. With this we will be able to explore long-standing questions such as why the atmospheric CO2 has changed over time during the last million years.
D. C. Kitover, R. van Balen, D. M. Roche, J. Vandenberghe, and H. Renssen
Geosci. Model Dev., 8, 1445–1460, https://doi.org/10.5194/gmd-8-1445-2015, https://doi.org/10.5194/gmd-8-1445-2015, 2015
M. Bügelmayer, D. M. Roche, and H. Renssen
The Cryosphere, 9, 821–835, https://doi.org/10.5194/tc-9-821-2015, https://doi.org/10.5194/tc-9-821-2015, 2015
K. A. Crichton, D. M. Roche, G. Krinner, and J. Chappellaz
Geosci. Model Dev., 7, 3111–3134, https://doi.org/10.5194/gmd-7-3111-2014, https://doi.org/10.5194/gmd-7-3111-2014, 2014
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Permafrost is ground that remains frozen for two or more consecutive years. An estimated 50% of the global below-ground organic carbon is stored in soils of the permafrost zone. This study presents the development and validation of a simplified permafrost-carbon mechanism for the CLIMBER-2 model. Our model development allows, for the first time, the study of the role of permafrost soils in the global carbon cycle for long timescales and for coupled palaeoclimate Earth system modelling studies.
T. Caley, D. M. Roche, C. Waelbroeck, and E. Michel
Clim. Past, 10, 1939–1955, https://doi.org/10.5194/cp-10-1939-2014, https://doi.org/10.5194/cp-10-1939-2014, 2014
D. M. Roche, C. Dumas, M. Bügelmayer, S. Charbit, and C. Ritz
Geosci. Model Dev., 7, 1377–1394, https://doi.org/10.5194/gmd-7-1377-2014, https://doi.org/10.5194/gmd-7-1377-2014, 2014
P. Beghin, S. Charbit, C. Dumas, M. Kageyama, D. M. Roche, and C. Ritz
Clim. Past, 10, 345–358, https://doi.org/10.5194/cp-10-345-2014, https://doi.org/10.5194/cp-10-345-2014, 2014
D. M. Roche
Geosci. Model Dev., 6, 1481–1491, https://doi.org/10.5194/gmd-6-1481-2013, https://doi.org/10.5194/gmd-6-1481-2013, 2013
D. M. Roche and T. Caley
Geosci. Model Dev., 6, 1493–1504, https://doi.org/10.5194/gmd-6-1493-2013, https://doi.org/10.5194/gmd-6-1493-2013, 2013
T. Caley and D. M. Roche
Geosci. Model Dev., 6, 1505–1516, https://doi.org/10.5194/gmd-6-1505-2013, https://doi.org/10.5194/gmd-6-1505-2013, 2013
J. Etourneau, L. G. Collins, V. Willmott, J.-H. Kim, L. Barbara, A. Leventer, S. Schouten, J. S. Sinninghe Damsté, A. Bianchini, V. Klein, X. Crosta, and G. Massé
Clim. Past, 9, 1431–1446, https://doi.org/10.5194/cp-9-1431-2013, https://doi.org/10.5194/cp-9-1431-2013, 2013
S. Charbit, C. Dumas, M. Kageyama, D. M. Roche, and C. Ritz
The Cryosphere, 7, 681–698, https://doi.org/10.5194/tc-7-681-2013, https://doi.org/10.5194/tc-7-681-2013, 2013
M. Kageyama, U. Merkel, B. Otto-Bliesner, M. Prange, A. Abe-Ouchi, G. Lohmann, R. Ohgaito, D. M. Roche, J. Singarayer, D. Swingedouw, and X Zhang
Clim. Past, 9, 935–953, https://doi.org/10.5194/cp-9-935-2013, https://doi.org/10.5194/cp-9-935-2013, 2013
R. Séférian, L. Bopp, D. Swingedouw, and J. Servonnat
Earth Syst. Dynam., 4, 109–127, https://doi.org/10.5194/esd-4-109-2013, https://doi.org/10.5194/esd-4-109-2013, 2013
P. Mathiot, H. Goosse, X. Crosta, B. Stenni, M. Braida, H. Renssen, C. J. Van Meerbeeck, V. Masson-Delmotte, A. Mairesse, and S. Dubinkina
Clim. Past, 9, 887–901, https://doi.org/10.5194/cp-9-887-2013, https://doi.org/10.5194/cp-9-887-2013, 2013
M. Casado, P. Ortega, V. Masson-Delmotte, C. Risi, D. Swingedouw, V. Daux, D. Genty, F. Maignan, O. Solomina, B. Vinther, N. Viovy, and P. Yiou
Clim. Past, 9, 871–886, https://doi.org/10.5194/cp-9-871-2013, https://doi.org/10.5194/cp-9-871-2013, 2013
P. Ortega, M. Montoya, F. González-Rouco, H. Beltrami, and D. Swingedouw
Clim. Past, 9, 547–565, https://doi.org/10.5194/cp-9-547-2013, https://doi.org/10.5194/cp-9-547-2013, 2013
J. Zumaque, F. Eynaud, S. Zaragosi, F. Marret, K. M. Matsuzaki, C. Kissel, D. M. Roche, B. Malaizé, E. Michel, I. Billy, T. Richter, and E. Palis
Clim. Past, 8, 1997–2017, https://doi.org/10.5194/cp-8-1997-2012, https://doi.org/10.5194/cp-8-1997-2012, 2012
V. Valsecchi, M. F. Sanchez Goñi, and L. Londeix
Clim. Past, 8, 1941–1956, https://doi.org/10.5194/cp-8-1941-2012, https://doi.org/10.5194/cp-8-1941-2012, 2012
Related subject area
Subject: Carbon Cycle | Archive: Modelling only | Timescale: Milankovitch
Modeling the evolution of pulse-like perturbations in atmospheric carbon and carbon isotopes: the role of weathering–sedimentation imbalances
Low terrestrial carbon storage at the Last Glacial Maximum: constraints from multi-proxy data
Simulation of climate, ice sheets and CO2 evolution during the last four glacial cycles with an Earth system model of intermediate complexity
The Plio-Pleistocene climatic evolution as a consequence of orbital forcing on the carbon cycle
Effects of eustatic sea-level change, ocean dynamics, and nutrient utilization on atmospheric pCO2 and seawater composition over the last 130 000 years: a model study
Impact of oceanic processes on the carbon cycle during the last termination
Impact of brine-induced stratification on the glacial carbon cycle
Glacial-interglacial atmospheric CO2 change: a possible "standing volume" effect on deep-ocean carbon sequestration
Aurich Jeltsch-Thömmes and Fortunat Joos
Clim. Past, 16, 423–451, https://doi.org/10.5194/cp-16-423-2020, https://doi.org/10.5194/cp-16-423-2020, 2020
Short summary
Short summary
Perturbations in atmospheric CO2 and in its isotopic composition, e.g., in response to carbon release from the land biosphere or from fossil fuel burning, evolve differently in time. We use an Earth system model of intermediate complexity to show that fluxes to and from the solid Earth play an important role in removing these perturbations from the atmosphere over thousands of years.
Aurich Jeltsch-Thömmes, Gianna Battaglia, Olivier Cartapanis, Samuel L. Jaccard, and Fortunat Joos
Clim. Past, 15, 849–879, https://doi.org/10.5194/cp-15-849-2019, https://doi.org/10.5194/cp-15-849-2019, 2019
Short summary
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A long-standing question in climate science is concerned with what processes contributed to the increase in atmospheric CO2 after the last ice age. From the range of possible processes we try to constrain the change in carbon storage in the land biosphere. By combining ice core and marine sediment data in a modeling framework we show that the carbon storage in the land biosphere increased largely after the last ice age. This will help to further understand processes at work in the Earth system.
Andrey Ganopolski and Victor Brovkin
Clim. Past, 13, 1695–1716, https://doi.org/10.5194/cp-13-1695-2017, https://doi.org/10.5194/cp-13-1695-2017, 2017
Short summary
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Ice cores reveal that atmospheric CO2 concentration varied synchronously with the global ice volume. Explaining the mechanism of glacial–interglacial variations of atmospheric CO2 concentrations and the link between CO2 and ice sheets evolution still remains a challenge. Here using the Earth system model of intermediate complexity we performed for the first time simulations of co-evolution of climate, ice sheets and carbon cycle using the astronomical forcing as the only external forcing.
Didier Paillard
Clim. Past, 13, 1259–1267, https://doi.org/10.5194/cp-13-1259-2017, https://doi.org/10.5194/cp-13-1259-2017, 2017
Short summary
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Ice ages are paced by astronomical parameters. On longer timescales, the astronomy also acts on climate, as evidenced by the 400 kyr signature observed in carbon isotopic records. In this paper, I present a conceptual model that links the astronomy to the dynamics of organic carbon in coastal areas. The model reproduces the carbon isotopic records and a two-step decrease in atmospheric CO2 that would explain the Pleistocene (~ 2.8 Myr BP) and mid-Pleistocene (~ 0.8 Myr BP) transition.
K. Wallmann, B. Schneider, and M. Sarnthein
Clim. Past, 12, 339–375, https://doi.org/10.5194/cp-12-339-2016, https://doi.org/10.5194/cp-12-339-2016, 2016
Short summary
Short summary
An Earth system model was set up and applied to evaluate the effects of sea-level change, ocean dynamics, and nutrient utilization on seawater composition and atmospheric pCO2 over the last glacial cycle. The model results strongly suggest that global sea-level change contributed significantly to the slow glacial decline in atmospheric pCO2 and the gradual pCO2 increase over the Holocene whereas the rapid deglacial pCO2 rise was induced by fast changes in ocean dynamics and nutrient utilization.
N. Bouttes, D. Paillard, D. M. Roche, C. Waelbroeck, M. Kageyama, A. Lourantou, E. Michel, and L. Bopp
Clim. Past, 8, 149–170, https://doi.org/10.5194/cp-8-149-2012, https://doi.org/10.5194/cp-8-149-2012, 2012
N. Bouttes, D. Paillard, and D. M. Roche
Clim. Past, 6, 575–589, https://doi.org/10.5194/cp-6-575-2010, https://doi.org/10.5194/cp-6-575-2010, 2010
L. C. Skinner
Clim. Past, 5, 537–550, https://doi.org/10.5194/cp-5-537-2009, https://doi.org/10.5194/cp-5-537-2009, 2009
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Short summary
Atmospheric CO2 is key for climate change. CO2 is lower during the oldest warm period of the last million years, the interglacials, than during the most recent ones (since 430 000 years ago). This difference has not been explained yet, but could be due to changes of ocean circulation. We test this hypothesis and the role of vegetation and ice sheets using an intermediate complexity model. We show that only small changes of CO2 can be obtained, underlying missing feedbacks or mechanisms.
Atmospheric CO2 is key for climate change. CO2 is lower during the oldest warm period of the...
