Articles | Volume 20, issue 12
https://doi.org/10.5194/cp-20-2719-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-20-2719-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
16 Dec 2024
Research article | Highlight paper |
| 16 Dec 2024
| 16 Dec 2024
Surface buoyancy control of millennial-scale variations in the Atlantic meridional ocean circulation
Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, P.O. Box 601203, 14412 Potsdam, Germany
Andrey Ganopolski
Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, P.O. Box 601203, 14412 Potsdam, Germany
Neil R. Edwards
Environment, Earth and Ecosystems, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
Stefan Rahmstorf
Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, P.O. Box 601203, 14412 Potsdam, Germany
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Andrey Ganopolski
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Takahito Mitsui, Matteo Willeit, and Niklas Boers
Earth Syst. Dynam., 14, 1277–1294, https://doi.org/10.5194/esd-14-1277-2023, https://doi.org/10.5194/esd-14-1277-2023, 2023
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Christine Kaufhold and Andrey Ganopolski
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Matteo Willeit, Tatiana Ilyina, Bo Liu, Christoph Heinze, Mahé Perrette, Malte Heinemann, Daniela Dalmonech, Victor Brovkin, Guy Munhoven, Janine Börker, Jens Hartmann, Gibran Romero-Mujalli, and Andrey Ganopolski
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Biogeosciences, 19, 4249–4265, https://doi.org/10.5194/bg-19-4249-2022, https://doi.org/10.5194/bg-19-4249-2022, 2022
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Andreas Wernecke, Tamsin L. Edwards, Isabel J. Nias, Philip B. Holden, and Neil R. Edwards
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Geosci. Model Dev., 12, 5137–5155, https://doi.org/10.5194/gmd-12-5137-2019, https://doi.org/10.5194/gmd-12-5137-2019, 2019
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We describe the development of the Paleoclimate PLASIM-GENIE emulator and its application to derive a high-resolution spatio-temporal description of the climate of the last 5 x 106 years. Spatial fields of bioclimatic variables are emulated at 1000-year intervals, driven by time series of scalar boundary-condition forcing (CO2, orbit, and ice volume). Emulated anomalies are interpolated into modern climatology to produce a high-resolution climate reconstruction of the Pliocene–Pleistocene.
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The Cryosphere, 13, 2281–2301, https://doi.org/10.5194/tc-13-2281-2019, https://doi.org/10.5194/tc-13-2281-2019, 2019
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Jamie D. Wilson, Stephen Barker, Neil R. Edwards, Philip B. Holden, and Andy Ridgwell
Biogeosciences, 16, 2923–2936, https://doi.org/10.5194/bg-16-2923-2019, https://doi.org/10.5194/bg-16-2923-2019, 2019
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The remains of plankton rain down from the surface ocean to the deep ocean, acting to store CO2 in the deep ocean. We used a model of biology and ocean circulation to explore the importance of this process in different regions of the ocean. The amount of CO2 stored in the deep ocean is most sensitive to changes in the Southern Ocean. As plankton in the Southern Ocean are likely those most impacted by future climate change, the amount of CO2 they store in the deep ocean could also be affected.
Krista M. S. Kemppinen, Philip B. Holden, Neil R. Edwards, Andy Ridgwell, and Andrew D. Friend
Clim. Past, 15, 1039–1062, https://doi.org/10.5194/cp-15-1039-2019, https://doi.org/10.5194/cp-15-1039-2019, 2019
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We simulate the Last Glacial Maximum atmospheric CO2 decrease with a large ensemble of parameter sets to investigate the range of possible physical and biogeochemical Earth system changes accompanying the CO2 decrease. Amongst the dominant ensemble changes is an increase in terrestrial carbon, which we attribute to a slower soil respiration rate, and the preservation of carbon by the LGM ice sheets. Further investigation into the role of terrestrial carbon is warranted.
Reinhard Calov, Sebastian Beyer, Ralf Greve, Johanna Beckmann, Matteo Willeit, Thomas Kleiner, Martin Rückamp, Angelika Humbert, and Andrey Ganopolski
The Cryosphere, 12, 3097–3121, https://doi.org/10.5194/tc-12-3097-2018, https://doi.org/10.5194/tc-12-3097-2018, 2018
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We present RCP 4.5 and 8.5 projections for the Greenland glacial system with the new glacial system model IGLOO 1.0, which incorporates the ice sheet model SICOPOLIS 3.3, a model of basal hydrology and a parameterization of submarine melt of outlet glaciers. Surface temperature and mass balance anomalies from the MAR climate model serve as forcing delivering projections for the contribution of the Greenland ice sheet to sea level rise and submarine melt of Helheim and Store outlet glaciers.
Matteo Willeit and Andrey Ganopolski
Clim. Past, 14, 697–707, https://doi.org/10.5194/cp-14-697-2018, https://doi.org/10.5194/cp-14-697-2018, 2018
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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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The Cryosphere, 12, 301–323, https://doi.org/10.5194/tc-12-301-2018, https://doi.org/10.5194/tc-12-301-2018, 2018
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Greenland's glaciers that are in contact with the ocean undergo a special ice–ocean melting. To project numerically Greenland's centennial contribution to sea level rise, it is crucial to incorporate this special melting. We demonstrate that a numerically cheap model shows the qualitative same behavior as numerical expensive 2–3-dimensional models and calculates the same melting as empirical data show. Our analytical solution gives some insight in the yet poorly understood melting behavior.
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
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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.
Eva Bauer and Andrey Ganopolski
Clim. Past, 13, 819–832, https://doi.org/10.5194/cp-13-819-2017, https://doi.org/10.5194/cp-13-819-2017, 2017
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Transient glacial cycle simulations with an EMIC and the PDD method require smaller melt factors for inception than for termination and larger factors for American than European ice sheets. The PDD online method with standard values simulates a sea level drop of 250 m at the LGM. The PDD online run reproducing the LGM ice volume has deficient ablation for reversing from glacial to interglacial climate, so termination is delayed. The SEB method with dust impact on snow albedo is seen as superior.
Mario Krapp, Alexander Robinson, and Andrey Ganopolski
The Cryosphere, 11, 1519–1535, https://doi.org/10.5194/tc-11-1519-2017, https://doi.org/10.5194/tc-11-1519-2017, 2017
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We present the snowpack model SEMIC. It calculates snow height, surface temperature, surface albedo, and the surface mass balance of snow- and ice-covered surfaces while using meteorological data as input. In this paper we describe how SEMIC works and how well it compares with snowpack data of a more sophisticated regional climate model applied to the Greenland ice sheet. Because of its simplicity and efficiency, SEMIC can be used as a coupling interface between atmospheric and ice sheet models.
Matteo Willeit and Andrey Ganopolski
Geosci. Model Dev., 9, 3817–3857, https://doi.org/10.5194/gmd-9-3817-2016, https://doi.org/10.5194/gmd-9-3817-2016, 2016
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PALADYN is presented; it is a new comprehensive and computationally efficient land surface–vegetation–carbon cycle model designed to be used in Earth system models of intermediate complexity for long-term simulations and paleoclimate studies.
Philip B. Holden, Neil R. Edwards, Klaus Fraedrich, Edilbert Kirk, Frank Lunkeit, and Xiuhua Zhu
Geosci. Model Dev., 9, 3347–3361, https://doi.org/10.5194/gmd-9-3347-2016, https://doi.org/10.5194/gmd-9-3347-2016, 2016
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We describe the development, tuning and climate of PLASIM–GENIE, a new intermediate complexity Atmosphere–Ocean General Circulation Model (AOGCM), built by coupling the Planet Simulator to the GENIE Earth system model.
Giang T. Tran, Kevin I. C. Oliver, András Sóbester, David J. J. Toal, Philip B. Holden, Robert Marsh, Peter Challenor, and Neil R. Edwards
Adv. Stat. Clim. Meteorol. Oceanogr., 2, 17–37, https://doi.org/10.5194/ascmo-2-17-2016, https://doi.org/10.5194/ascmo-2-17-2016, 2016
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In this work, we combine the information from a complex and a simple atmospheric model to efficiently build a statistical representation (an emulator) of the complex model and to study the relationship between them. Thanks to the improved efficiency, this process is now feasible for complex models, which are slow and costly to run. The constructed emulator provide approximations of the model output, allowing various analyses to be made without the need to run the complex model again.
A. M. Foley, P. B. Holden, N. R. Edwards, J.-F. Mercure, P. Salas, H. Pollitt, and U. Chewpreecha
Earth Syst. Dynam., 7, 119–132, https://doi.org/10.5194/esd-7-119-2016, https://doi.org/10.5194/esd-7-119-2016, 2016
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We introduce GENIEem-PLASIM-ENTSem (GPem), a climate-carbon cycle emulator, showing how model emulation can be used in integrated assessment modelling to resolve regional climate impacts and systematically capture uncertainty. In a case study, we couple GPem to FTT:Power-E3MG, a non-equilibrium economic model with technology diffusion. We find that when the electricity sector is decarbonised by 90 %, further emissions reductions must be achieved in other sectors to avoid dangerous climate change.
M. Willeit and A. Ganopolski
Clim. Past, 11, 1165–1180, https://doi.org/10.5194/cp-11-1165-2015, https://doi.org/10.5194/cp-11-1165-2015, 2015
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In this paper we explore the permafrost–ice-sheet interaction using the fully coupled climate–ice-sheet model CLIMBER-2 with the addition of a newly developed permafrost module. We find that permafrost has a moderate but significant effect on ice sheet dynamics during the last glacial cycle. In particular at the Last Glacial Maximum the inclusion of permafrost leads to a 15m sea level equivalent increase in Northern Hemisphere ice volume when permafrost is included.
R. Calov, A. Robinson, M. Perrette, and A. Ganopolski
The Cryosphere, 9, 179–196, https://doi.org/10.5194/tc-9-179-2015, https://doi.org/10.5194/tc-9-179-2015, 2015
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Ice discharge into the ocean from outlet glaciers is an important
component of mass loss of the Greenland ice sheet. Here, we present a
simple parameterization of ice discharge for coarse resolution ice
sheet models, suitable for large ensembles or long-term palaeo
simulations. This parameterization reproduces in a good approximation
the present-day ice discharge compared with estimates, and the
simulation of the present-day ice sheet elevation is considerably
improved.
E. Bauer and A. Ganopolski
Clim. Past, 10, 1333–1348, https://doi.org/10.5194/cp-10-1333-2014, https://doi.org/10.5194/cp-10-1333-2014, 2014
D. Dalmonech, A. M. Foley, A. Anav, P. Friedlingstein, A. D. Friend, M. Kidston, M. Willeit, and S. Zaehle
Biogeosciences Discuss., https://doi.org/10.5194/bgd-11-2083-2014, https://doi.org/10.5194/bgd-11-2083-2014, 2014
Revised manuscript has not been submitted
M. Willeit, A. Ganopolski, and G. Feulner
Biogeosciences, 11, 17–32, https://doi.org/10.5194/bg-11-17-2014, https://doi.org/10.5194/bg-11-17-2014, 2014
M. Willeit, A. Ganopolski, and G. Feulner
Clim. Past, 9, 1749–1759, https://doi.org/10.5194/cp-9-1749-2013, https://doi.org/10.5194/cp-9-1749-2013, 2013
Related subject area
Subject: Climate Modelling | Archive: Modelling only | Timescale: Millenial/D-O
High-resolution LGM climate of Europe and the Alpine region using the regional climate model WRF
Causes of the weak emergent constraint on climate sensitivity at the Last Glacial Maximum
Does a difference in ice sheets between Marine Isotope Stages 3 and 5a affect the duration of stadials? Implications from hosing experiments
Impact of mid-glacial ice sheets on deep ocean circulation and global climate
A Bayesian framework for emergent constraints: case studies of climate sensitivity with PMIP
Equilibrium simulations of Marine Isotope Stage 3 climate
Heinrich events show two-stage climate response in transient glacial simulations
Hosed vs. unhosed: interruptions of the Atlantic Meridional Overturning Circulation in a global coupled model, with and without freshwater forcing
The climate reconstruction in Shandong Peninsula, northern China, during the last millennium based on stalagmite laminae together with a comparison to δ18O
Variability of daily winter wind speed distribution over Northern Europe during the past millennium in regional and global climate simulations
Last interglacial model–data mismatch of thermal maximum temperatures partially explained
Hindcasting the continuum of Dansgaard–Oeschger variability: mechanisms, patterns and timing
Climatic impacts of fresh water hosing under Last Glacial Maximum conditions: a multi-model study
A mechanism for dust-induced destabilization of glacial climates
The climate in the Baltic Sea region during the last millennium simulated with a regional climate model
Role of CO2 and Southern Ocean winds in glacial abrupt climate change
Heinrich event 1: an example of dynamical ice-sheet reaction to oceanic changes
Weakened atmospheric energy transport feedback in cold glacial climates
Water vapour source impacts on oxygen isotope variability in tropical precipitation during Heinrich events
Glacial climate sensitivity to different states of the Atlantic Meridional Overturning Circulation: results from the IPSL model
Emmanuele Russo, Jonathan Buzan, Sebastian Lienert, Guillaume Jouvet, Patricio Velasquez Alvarez, Basil Davis, Patrick Ludwig, Fortunat Joos, and Christoph C. Raible
Clim. Past, 20, 449–465, https://doi.org/10.5194/cp-20-449-2024, https://doi.org/10.5194/cp-20-449-2024, 2024
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We present a series of experiments conducted for the Last Glacial Maximum (~21 ka) over Europe using the regional climate Weather Research and Forecasting model (WRF) at convection-permitting resolutions. The model, with new developments better suited to paleo-studies, agrees well with pollen-based climate reconstructions. This agreement is improved when considering different sources of uncertainty. The effect of convection-permitting resolutions is also assessed.
Martin Renoult, Navjit Sagoo, Jiang Zhu, and Thorsten Mauritsen
Clim. Past, 19, 323–356, https://doi.org/10.5194/cp-19-323-2023, https://doi.org/10.5194/cp-19-323-2023, 2023
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The relationship between the Last Glacial Maximum and the sensitivity of climate models to a doubling of CO2 can be used to estimate the true sensitivity of the Earth. However, this relationship has varied in successive model generations. In this study, we assess multiple processes at the Last Glacial Maximum which weaken this relationship. For example, how models respond to the presence of ice sheets is a large contributor of uncertainty.
Sam Sherriff-Tadano, Ayako Abe-Ouchi, Akira Oka, Takahito Mitsui, and Fuyuki Saito
Clim. Past, 17, 1919–1936, https://doi.org/10.5194/cp-17-1919-2021, https://doi.org/10.5194/cp-17-1919-2021, 2021
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Glacial periods underwent climate shifts between warm states and cold states on a millennial timescale. Frequency of these climate shifts varied along time: it was shorter during mid-glacial period compared to early glacial period. Here, from climate simulations of early and mid-glacial periods with a comprehensive climate model, we show that the larger ice sheet in the mid-glacial compared to early glacial periods could contribute to the frequent climate shifts during the mid-glacial period.
Sam Sherriff-Tadano, Ayako Abe-Ouchi, and Akira Oka
Clim. Past, 17, 95–110, https://doi.org/10.5194/cp-17-95-2021, https://doi.org/10.5194/cp-17-95-2021, 2021
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We perform simulations of Marine Isotope Stage 3 and 5a with an atmosphere–ocean general circulation model to explore the effect of the southward expansion of mid-glacial ice sheets on the Atlantic Meridional Overturning Circulation (AMOC) and climate. We find that the southward expansion of the mid-glacial ice sheet causes a surface cooling over the North Atlantic and Southern Ocean, but it exerts a small impact on the AMOC due to the competing effects of surface wind and surface cooling.
Martin Renoult, James Douglas Annan, Julia Catherine Hargreaves, Navjit Sagoo, Clare Flynn, Marie-Luise Kapsch, Qiang Li, Gerrit Lohmann, Uwe Mikolajewicz, Rumi Ohgaito, Xiaoxu Shi, Qiong Zhang, and Thorsten Mauritsen
Clim. Past, 16, 1715–1735, https://doi.org/10.5194/cp-16-1715-2020, https://doi.org/10.5194/cp-16-1715-2020, 2020
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Interest in past climates as sources of information for the climate system has grown in recent years. In particular, studies of the warm mid-Pliocene and cold Last Glacial Maximum showed relationships between the tropical surface temperature of the Earth and its sensitivity to an abrupt doubling of atmospheric CO2. In this study, we develop a new and promising statistical method and obtain similar results as previously observed, wherein the sensitivity does not seem to exceed extreme values.
Chuncheng Guo, Kerim H. Nisancioglu, Mats Bentsen, Ingo Bethke, and Zhongshi Zhang
Clim. Past, 15, 1133–1151, https://doi.org/10.5194/cp-15-1133-2019, https://doi.org/10.5194/cp-15-1133-2019, 2019
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We present an equilibrium simulation of the climate of Marine Isotope Stage 3, with an IPCC-class model with a relatively high model resolution and a long integration. The simulated climate resembles a warm interstadial state, as indicated by reconstructions of Greenland temperature, sea ice extent, and AMOC. Sensitivity experiments to changes in atmospheric CO2 levels and ice sheet size show that the model is in a relatively stable climate state without multiple equilibria.
Florian Andreas Ziemen, Marie-Luise Kapsch, Marlene Klockmann, and Uwe Mikolajewicz
Clim. Past, 15, 153–168, https://doi.org/10.5194/cp-15-153-2019, https://doi.org/10.5194/cp-15-153-2019, 2019
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Heinrich events are among the dominant modes of glacial climate variability. They are caused by massive ice discharges from the Laurentide Ice Sheet into the North Atlantic. In previous studies, the climate changes were either seen as resulting from freshwater released from the melt of the discharged icebergs or by ice sheet elevation changes. With a coupled ice sheet–climate model, we show that both effects are relevant with the freshwater effects preceding the ice sheet elevation effects.
Nicolas Brown and Eric D. Galbraith
Clim. Past, 12, 1663–1679, https://doi.org/10.5194/cp-12-1663-2016, https://doi.org/10.5194/cp-12-1663-2016, 2016
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An Earth system model is used to explore variability in the global impacts of AMOC disruptions. The model exhibits spontaneous AMOC oscillations under particular boundary conditions, which we compare with freshwater-forced disruptions. We find that the global impacts are similar whether the AMOC disruptions are spontaneous or forced. Freshwater forcing generally amplifies the global impacts, with tropical precipitation and the stability of polar haloclines showing particular sensitivity.
Qing Wang, Houyun Zhou, Ke Cheng, Hong Chi, Chuan-Chou Shen, Changshan Wang, and Qianqian Ma
Clim. Past, 12, 871–881, https://doi.org/10.5194/cp-12-871-2016, https://doi.org/10.5194/cp-12-871-2016, 2016
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The upper part of stalagmite ky1 (from top to 42.769 mm depth), consisting of 678 laminae, was collected from a cave in northern China, located in the East Asia monsoon area. The time of deposition ranges from AD 1217±20 to 1894±20. The analysis shows that both the variations in the thickness of the laminae themselves and the fluctuating degree of variation in the thickness of the laminae of stalagmite ky1 have obviously staged characteristics and synchronized with climate.
Svenja E. Bierstedt, Birgit Hünicke, Eduardo Zorita, Sebastian Wagner, and Juan José Gómez-Navarro
Clim. Past, 12, 317–338, https://doi.org/10.5194/cp-12-317-2016, https://doi.org/10.5194/cp-12-317-2016, 2016
P. Bakker and H. Renssen
Clim. Past, 10, 1633–1644, https://doi.org/10.5194/cp-10-1633-2014, https://doi.org/10.5194/cp-10-1633-2014, 2014
L. Menviel, A. Timmermann, T. Friedrich, and M. H. England
Clim. Past, 10, 63–77, https://doi.org/10.5194/cp-10-63-2014, https://doi.org/10.5194/cp-10-63-2014, 2014
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
B. F. Farrell and D. S. Abbot
Clim. Past, 8, 2061–2067, https://doi.org/10.5194/cp-8-2061-2012, https://doi.org/10.5194/cp-8-2061-2012, 2012
S. Schimanke, H. E. M. Meier, E. Kjellström, G. Strandberg, and R. Hordoir
Clim. Past, 8, 1419–1433, https://doi.org/10.5194/cp-8-1419-2012, https://doi.org/10.5194/cp-8-1419-2012, 2012
R. Banderas, J. Álvarez-Solas, and M. Montoya
Clim. Past, 8, 1011–1021, https://doi.org/10.5194/cp-8-1011-2012, https://doi.org/10.5194/cp-8-1011-2012, 2012
J. Álvarez-Solas, M. Montoya, C. Ritz, G. Ramstein, S. Charbit, C. Dumas, K. Nisancioglu, T. Dokken, and A. Ganopolski
Clim. Past, 7, 1297–1306, https://doi.org/10.5194/cp-7-1297-2011, https://doi.org/10.5194/cp-7-1297-2011, 2011
I. Cvijanovic, P. L. Langen, and E. Kaas
Clim. Past, 7, 1061–1073, https://doi.org/10.5194/cp-7-1061-2011, https://doi.org/10.5194/cp-7-1061-2011, 2011
S. C. Lewis, A. N. LeGrande, M. Kelley, and G. A. Schmidt
Clim. Past, 6, 325–343, https://doi.org/10.5194/cp-6-325-2010, https://doi.org/10.5194/cp-6-325-2010, 2010
M. Kageyama, J. Mignot, D. Swingedouw, C. Marzin, R. Alkama, and O. Marti
Clim. Past, 5, 551–570, https://doi.org/10.5194/cp-5-551-2009, https://doi.org/10.5194/cp-5-551-2009, 2009
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Hodell, D. A., Crowhurst, S. J., Lourens, L., Margari, V., Nicolson, J., Rolfe, J. E., Skinner, L. C., Thomas, N. C., Tzedakis, P. C., Mleneck-Vautravers, M. J., and Wolff, E. W.: A 1.5-million-year record of orbital and millennial climate variability in the North Atlantic, Clim. Past, 19, 607–636, https://doi.org/10.5194/cp-19-607-2023, 2023. a, b
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Co-editor-in-chief
The Atlantic Meridional Overturning Circulation (AMOC) is at its weakest of the last millennium and is projected to further weaken over the coming decades, with the risk of a collapse over the coming century non negligible. The geologic record provides examples of rapid and large AMOC variations, with phases of AMOC weakening, preceding an AMOC shutdown. One key question is whether CO2-driven AMOC weakening is reversible, or whether it represents a tipping point, which might lead to an AMOC collapse. The study by Willeit et al. offers a new diagnostic that is simple to implement and allows for comparing AMOC stability between different models, as well as different time periods. This offers a powerful new tool in understanding the conditions for AMOC stability, and thus the AMOC future.
The Atlantic Meridional Overturning Circulation (AMOC) is at its weakest of the last millennium...
Short summary
Using an Earth system model that can simulate Dansgaard–Oeschger-like events, we show that conditions under which millennial-scale climate variability occurs are related to the integrated surface buoyancy flux over the northern North Atlantic. This newly defined buoyancy measure explains why millennial-scale climate variability arising from abrupt changes in the Atlantic meridional overturning circulation occurred for mid-glacial conditions but not for interglacial or full glacial conditions.
Using an Earth system model that can simulate Dansgaard–Oeschger-like events, we show that...
