Articles | Volume 10, issue 1
https://doi.org/10.5194/cp-10-41-2014
© 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-10-41-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
10 Jan 2014
Research article |
| 10 Jan 2014
Mending Milankovitch's theory: obliquity amplification by surface feedbacks
C. R. Tabor
Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA
C. J. Poulsen
Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA
D. Pollard
Earth and Environmental Systems Institute, Pennsylvania State University, State College, PA, USA
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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.
Jiang Zhu and Christopher J. Poulsen
Clim. Past, 17, 253–267, https://doi.org/10.5194/cp-17-253-2021, https://doi.org/10.5194/cp-17-253-2021, 2021
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Climate sensitivity has been directly calculated from paleoclimate data. This approach relies on good understandings of climate forcings and interactions within the Earth system. We conduct Last Glacial Maximum simulations using a climate model to quantify the forcing and efficacy of ice sheets and greenhouse gases and to directly estimate climate sensitivity in the model. Results suggest that the direct calculation overestimates the truth by 25 % due to neglecting ocean dynamical feedback.
Daniel J. Lunt, Fran Bragg, Wing-Le Chan, David K. Hutchinson, Jean-Baptiste Ladant, Polina Morozova, Igor Niezgodzki, Sebastian Steinig, Zhongshi Zhang, Jiang Zhu, Ayako Abe-Ouchi, Eleni Anagnostou, Agatha M. de Boer, Helen K. Coxall, Yannick Donnadieu, Gavin Foster, Gordon N. Inglis, Gregor Knorr, Petra M. Langebroek, Caroline H. Lear, Gerrit Lohmann, Christopher J. Poulsen, Pierre Sepulchre, Jessica E. Tierney, Paul J. Valdes, Evgeny M. Volodin, Tom Dunkley Jones, Christopher J. Hollis, Matthew Huber, and Bette L. Otto-Bliesner
Clim. Past, 17, 203–227, https://doi.org/10.5194/cp-17-203-2021, https://doi.org/10.5194/cp-17-203-2021, 2021
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This paper presents the first modelling results from the Deep-Time Model Intercomparison Project (DeepMIP), in which we focus on the early Eocene climatic optimum (EECO, 50 million years ago). We show that, in contrast to previous work, at least three models (CESM, GFDL, and NorESM) produce climate states that are consistent with proxy indicators of global mean temperature and polar amplification, and they achieve this at a CO2 concentration that is consistent with the CO2 proxy record.
David Pollard and Robert M. DeConto
Geosci. Model Dev., 13, 6481–6500, https://doi.org/10.5194/gmd-13-6481-2020, https://doi.org/10.5194/gmd-13-6481-2020, 2020
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Buttressing by floating ice shelves at ice-sheet grounding lines is an
important process that affects ice retreat and whether structural failure
occurs in deep bathymetry. Here, we use a simple algorithm to better
represent 2-D grounding-line curvature in an ice-sheet model. Along with other
enhancements, this improves the performance in idealized-fjord intercomparisons
and enables better diagnosis of potential structural failure at future
retreating Antarctic grounding lines.
Dipayan Choudhury, Axel Timmermann, Fabian Schloesser, Malte Heinemann, and David Pollard
Clim. Past, 16, 2183–2201, https://doi.org/10.5194/cp-16-2183-2020, https://doi.org/10.5194/cp-16-2183-2020, 2020
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Our study is the first study to conduct transient simulations over MIS 7, using a 3-D coupled climate–ice sheet model with interactive ice sheets in both hemispheres. We find glacial inceptions to be more sensitive to orbital variations, whereas glacial terminations need the concerted action of both orbital and CO2 forcings. We highlight the issue of multiple equilibria and an instability due to stationary-wave–topography feedback that can trigger unrealistic North American ice sheet growth.
Stephen L. Cornford, Helene Seroussi, Xylar S. Asay-Davis, G. Hilmar Gudmundsson, Rob Arthern, Chris Borstad, Julia Christmann, Thiago Dias dos Santos, Johannes Feldmann, Daniel Goldberg, Matthew J. Hoffman, Angelika Humbert, Thomas Kleiner, Gunter Leguy, William H. Lipscomb, Nacho Merino, Gaël Durand, Mathieu Morlighem, David Pollard, Martin Rückamp, C. Rosie Williams, and Hongju Yu
The Cryosphere, 14, 2283–2301, https://doi.org/10.5194/tc-14-2283-2020, https://doi.org/10.5194/tc-14-2283-2020, 2020
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We present the results of the third Marine Ice Sheet Intercomparison Project (MISMIP+). MISMIP+ is one in a series of exercises that test numerical models of ice sheet flow in simple situations. This particular exercise concentrates on the response of ice sheet models to the thinning of their floating ice shelves, which is of interest because numerical models are currently used to model the response to contemporary and near-future thinning in Antarctic ice shelves.
Jean-Baptiste Ladant, Christopher J. Poulsen, Frédéric Fluteau, Clay R. Tabor, Kenneth G. MacLeod, Ellen E. Martin, Shannon J. Haynes, and Masoud A. Rostami
Clim. Past, 16, 973–1006, https://doi.org/10.5194/cp-16-973-2020, https://doi.org/10.5194/cp-16-973-2020, 2020
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Understanding of the role of ocean circulation on climate is contingent on the ability to reconstruct its modes and evolution. Here, we show that earth system model simulations of the Late Cretaceous predict major changes in ocean circulation as a result of paleogeographic and gateway evolution. Comparisons of model results with available data compilations demonstrate reasonable agreement but highlight that various plausible theories of ocean circulation change coexist during this period.
Anders Levermann, Ricarda Winkelmann, Torsten Albrecht, Heiko Goelzer, Nicholas R. Golledge, Ralf Greve, Philippe Huybrechts, Jim Jordan, Gunter Leguy, Daniel Martin, Mathieu Morlighem, Frank Pattyn, David Pollard, Aurelien Quiquet, Christian Rodehacke, Helene Seroussi, Johannes Sutter, Tong Zhang, Jonas Van Breedam, Reinhard Calov, Robert DeConto, Christophe Dumas, Julius Garbe, G. Hilmar Gudmundsson, Matthew J. Hoffman, Angelika Humbert, Thomas Kleiner, William H. Lipscomb, Malte Meinshausen, Esmond Ng, Sophie M. J. Nowicki, Mauro Perego, Stephen F. Price, Fuyuki Saito, Nicole-Jeanne Schlegel, Sainan Sun, and Roderik S. W. van de Wal
Earth Syst. Dynam., 11, 35–76, https://doi.org/10.5194/esd-11-35-2020, https://doi.org/10.5194/esd-11-35-2020, 2020
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We provide an estimate of the future sea level contribution of Antarctica from basal ice shelf melting up to the year 2100. The full uncertainty range in the warming-related forcing of basal melt is estimated and applied to 16 state-of-the-art ice sheet models using a linear response theory approach. The sea level contribution we obtain is very likely below 61 cm under unmitigated climate change until 2100 (RCP8.5) and very likely below 40 cm if the Paris Climate Agreement is kept.
Michelle Tigchelaar, Axel Timmermann, Tobias Friedrich, Malte Heinemann, and David Pollard
The Cryosphere, 13, 2615–2631, https://doi.org/10.5194/tc-13-2615-2019, https://doi.org/10.5194/tc-13-2615-2019, 2019
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The Antarctic Ice Sheet has expanded and retracted often in the past, but, so far, studies have not identified which environmental driver is most important: air temperature, snowfall, ocean conditions or global sea level. In a modeling study of 400 000 years of Antarctic Ice Sheet variability we isolated different drivers and found that no single driver dominates. Air temperature and sea level are most important and combine in a synergistic way, with important implications for future change.
Hélène Seroussi, Sophie Nowicki, Erika Simon, Ayako Abe-Ouchi, Torsten Albrecht, Julien Brondex, Stephen Cornford, Christophe Dumas, Fabien Gillet-Chaulet, Heiko Goelzer, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Thomas Kleiner, Eric Larour, Gunter Leguy, William H. Lipscomb, Daniel Lowry, Matthias Mengel, Mathieu Morlighem, Frank Pattyn, Anthony J. Payne, David Pollard, Stephen F. Price, Aurélien Quiquet, Thomas J. Reerink, Ronja Reese, Christian B. Rodehacke, Nicole-Jeanne Schlegel, Andrew Shepherd, Sainan Sun, Johannes Sutter, Jonas Van Breedam, Roderik S. W. van de Wal, Ricarda Winkelmann, and Tong Zhang
The Cryosphere, 13, 1441–1471, https://doi.org/10.5194/tc-13-1441-2019, https://doi.org/10.5194/tc-13-1441-2019, 2019
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We compare a wide range of Antarctic ice sheet simulations with varying initialization techniques and model parameters to understand the role they play on the projected evolution of this ice sheet under simple scenarios. Results are improved compared to previous assessments and show that continued improvements in the representation of the floating ice around Antarctica are critical to reduce the uncertainty in the future ice sheet contribution to sea level rise.
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.
David Pollard, Robert M. DeConto, and Richard B. Alley
Geosci. Model Dev., 11, 5149–5172, https://doi.org/10.5194/gmd-11-5149-2018, https://doi.org/10.5194/gmd-11-5149-2018, 2018
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Around the margins of ice sheets in contact with the ocean, calving of icebergs can generate large amounts of floating ice debris called "mélange". In major Greenland fjords, mélange significantly slows down ice flow from upstream. Our study applies numerical models to past and possible future episodes of rapid Antarctic Ice Sheet retreat. We find that, due to larger spatial scales, Antarctic mélange does not significantly impede flow or slow ice retreat and associated sea level rise.
Perry Spector, John Stone, David Pollard, Trevor Hillebrand, Cameron Lewis, and Joel Gombiner
The Cryosphere, 12, 2741–2757, https://doi.org/10.5194/tc-12-2741-2018, https://doi.org/10.5194/tc-12-2741-2018, 2018
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Cosmogenic-nuclide analyses in bedrock recovered from below the West Antarctic Ice Sheet have the potential to establish whether and when large-scale deglaciation occurred in the past. Here we (i) discuss the criteria and considerations for subglacial drill sites, (ii) evaluate candidate sites in West Antarctica, and (iii) describe reconnaissance at three West Antarctic sites, focusing on the Pirrit Hills, which we present as a case study of site selection on the scale of an individual nunatak.
Clemens Schannwell, Stephen Cornford, David Pollard, and Nicholas E. Barrand
The Cryosphere, 12, 2307–2326, https://doi.org/10.5194/tc-12-2307-2018, https://doi.org/10.5194/tc-12-2307-2018, 2018
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Despite the speculation on the state and fate of Larsen C Ice Shelf, a key unknown factor remains: what would be the effects of ice-shelf collapse on upstream drainage basins and thus global sea levels? In our paper three state-of-the-art numerical ice-sheet models were used to simulate the volume evolution of the inland ice sheet to ice-shelf collapse at Larsen C and George VI ice shelves. Our results suggest sea-level rise of up to ~ 4 mm for Larsen C ice shelf and ~ 22 for George VI ice shelf.
Daniel J. Lunt, Matthew Huber, Eleni Anagnostou, Michiel L. J. Baatsen, Rodrigo Caballero, Rob DeConto, Henk A. Dijkstra, Yannick Donnadieu, David Evans, Ran Feng, Gavin L. Foster, Ed Gasson, Anna S. von der Heydt, Chris J. Hollis, Gordon N. Inglis, Stephen M. Jones, Jeff Kiehl, Sandy Kirtland Turner, Robert L. Korty, Reinhardt Kozdon, Srinath Krishnan, Jean-Baptiste Ladant, Petra Langebroek, Caroline H. Lear, Allegra N. LeGrande, Kate Littler, Paul Markwick, Bette Otto-Bliesner, Paul Pearson, Christopher J. Poulsen, Ulrich Salzmann, Christine Shields, Kathryn Snell, Michael Stärz, James Super, Clay Tabor, Jessica E. Tierney, Gregory J. L. Tourte, Aradhna Tripati, Garland R. Upchurch, Bridget S. Wade, Scott L. Wing, Arne M. E. Winguth, Nicky M. Wright, James C. Zachos, and Richard E. Zeebe
Geosci. Model Dev., 10, 889–901, https://doi.org/10.5194/gmd-10-889-2017, https://doi.org/10.5194/gmd-10-889-2017, 2017
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In this paper we describe the experimental design for a set of simulations which will be carried out by a range of climate models, all investigating the climate of the Eocene, about 50 million years ago. The intercomparison of model results is called 'DeepMIP', and we anticipate that we will contribute to the next IPCC report through an analysis of these simulations and the geological data to which we will compare them.
David Pollard, Won Chang, Murali Haran, Patrick Applegate, and Robert DeConto
Geosci. Model Dev., 9, 1697–1723, https://doi.org/10.5194/gmd-9-1697-2016, https://doi.org/10.5194/gmd-9-1697-2016, 2016
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Computer modeling of variations of the Antarctic Ice Sheet help to
understand the ice sheet's sensitivity to climate change. We apply
a numerical model to its retreat over the last 20 000 years, from its
maximum glacial extent to modern. An ensemble of 625 simulations is performed
with systematic combinations of uncertain model parameter values. Results are
analyzed using (1) simple averaging, and (2) advanced statistical techniques,
and reasonable agreement is found between the two.
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. Levermann, R. Winkelmann, S. Nowicki, J. L. Fastook, K. Frieler, R. Greve, H. H. Hellmer, M. A. Martin, M. Meinshausen, M. Mengel, A. J. Payne, D. Pollard, T. Sato, R. Timmermann, W. L. Wang, and R. A. Bindschadler
Earth Syst. Dynam., 5, 271–293, https://doi.org/10.5194/esd-5-271-2014, https://doi.org/10.5194/esd-5-271-2014, 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
R. Briggs, D. Pollard, and L. Tarasov
The Cryosphere, 7, 1949–1970, https://doi.org/10.5194/tc-7-1949-2013, https://doi.org/10.5194/tc-7-1949-2013, 2013
Y. Goddéris, S. L. Brantley, L. M. François, J. Schott, D. Pollard, M. Déqué, and M. Dury
Biogeosciences, 10, 135–148, https://doi.org/10.5194/bg-10-135-2013, https://doi.org/10.5194/bg-10-135-2013, 2013
Related subject area
Subject: Climate Modelling | Archive: Modelling only | Timescale: Milankovitch
Large-ensemble simulations of the North American and Greenland ice sheets at the Last Glacial Maximum with a coupled atmospheric general circulation–ice sheet model
New estimation of critical insolation–CO2 relationship for triggering glacial inception
Antarctic climate response in Last-Interglacial simulations using the Community Earth System Model (CESM2)
Toward generalized Milankovitch theory (GMT)
Unraveling the complexities of the Last Glacial Maximum climate: the role of individual boundary conditions and forcings
Do phenomenological dynamical paleoclimate models have physical similarity with Nature? Seemingly, not all of them do
Deglacial climate changes as forced by different ice sheet reconstructions
The coupled system response to 250 years of freshwater forcing: Last Interglacial CMIP6–PMIP4 HadGEM3 simulations
An energy budget approach to understand the Arctic warming during the Last Interglacial
Milankovitch, the father of paleoclimate modeling
Greenland climate simulations show high Eemian surface melt which could explain reduced total air content in ice cores
The response of tropical precipitation to Earth's precession: the role of energy fluxes and vertical stability
Interhemispheric effect of global geography on Earth's climate response to orbital forcing
Link between the North Atlantic Oscillation and the surface mass balance components of the Greenland Ice Sheet under preindustrial and last interglacial climates: a study with a coupled global circulation model
Eemian Greenland SMB strongly sensitive to model choice
The importance of snow albedo for ice sheet evolution over the last glacial cycle
Comparison of surface mass balance of ice sheets simulated by positive-degree-day method and energy balance approach
Sea ice led to poleward-shifted winds at the Last Glacial Maximum: the influence of state dependency on CMIP5 and PMIP3 models
The effect of a dynamic soil scheme on the climate of the mid-Holocene and the Last Glacial Maximum
Obliquity forcing of low-latitude climate
Modelling of mineral dust for interglacial and glacial climate conditions with a focus on Antarctica
Coupled ice sheet–climate modeling under glacial and pre-industrial boundary conditions
Relative impact of insolation and the Indo-Pacific warm pool surface temperature on the East Asia summer monsoon during the MIS-13 interglacial
Factors controlling the last interglacial climate as simulated by LOVECLIM1.3
Deglacial ice sheet meltdown: orbital pacemaking and CO2 effects
Statistical downscaling of a climate simulation of the last glacial cycle: temperature and precipitation over Northern Europe
Impact of precession on the climate, vegetation and fire activity in southern Africa during MIS4
Megalake Chad impact on climate and vegetation during the late Pliocene and the mid-Holocene
Modeling the climatic implications and indicative senses of the Guliya δ18O-temperature proxy record to the ocean–atmosphere system during the past 130 ka
Quantification of the Greenland ice sheet contribution to Last Interglacial sea level rise
Southern westerlies in LGM and future (RCP4.5) climates
Inferred gas hydrate and permafrost stability history models linked to climate change in the Beaufort-Mackenzie Basin, Arctic Canada
The role of orbital forcing, carbon dioxide and regolith in 100 kyr glacial cycles
Methane variations on orbital timescales: a transient modeling experiment
Deciphering the spatio-temporal complexity of climate change of the last deglaciation: a model analysis
Effects of orbital forcing on atmosphere and ocean heat transports in Holocene and Eemian climate simulations with a comprehensive Earth system model
Investigating the evolution of major Northern Hemisphere ice sheets during the last glacial-interglacial cycle
Individual and combined effects of ice sheets and precession on MIS-13 climate
Sam Sherriff-Tadano, Ruza Ivanovic, Lauren Gregoire, Charlotte Lang, Niall Gandy, Jonathan Gregory, Tamsin L. Edwards, Oliver Pollard, and Robin S. Smith
Clim. Past, 20, 1489–1512, https://doi.org/10.5194/cp-20-1489-2024, https://doi.org/10.5194/cp-20-1489-2024, 2024
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Ensemble simulations of the climate and ice sheets of the Last Glacial Maximum (LGM) are performed with a new coupled climate–ice sheet model. Results show a strong sensitivity of the North American ice sheet to the albedo scheme, while the Greenland ice sheet appeared more sensitive to basal sliding schemes. Our result implies a potential connection between the North American ice sheet at the LGM and the future Greenland ice sheet through the albedo scheme.
Stefanie Talento, Matteo Willeit, and Andrey Ganopolski
Clim. Past, 20, 1349–1364, https://doi.org/10.5194/cp-20-1349-2024, https://doi.org/10.5194/cp-20-1349-2024, 2024
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To trigger glacial inception, the summer maximum insolation at high latitudes in the Northern Hemisphere must be lower than a critical value. This value is not constant but depends on the atmospheric CO2 concentration. Paleoclimatic data do not give enough information to derive the relationship between the critical threshold and CO2. However, knowledge of such a relation is important for predicting future glaciations and the impact anthropogenic CO2 emissions might have on them.
Mira Berdahl, Gunter R. Leguy, William H. Lipscomb, Bette L. Otto-Bliesner, Esther C. Brady, Robert A. Tomas, Nathan M. Urban, Ian Miller, Harriet Morgan, and Eric J. Steig
Clim. Past Discuss., https://doi.org/10.5194/cp-2024-19, https://doi.org/10.5194/cp-2024-19, 2024
Preprint under review for CP
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Studying climate conditions near the Antarctic ice sheet (AIS) during Earth’s past warm periods informs us about how global warming may influence AIS ice loss. Using a global climate model, we investigate climate conditions near the AIS during the Last Interglacial (129 to 116 kyr ago), a period with warmer global temperatures and higher sea level than today. We identify the orbital and freshwater forcings that could cause ice loss and probe the mechanisms that lead to warmer climate conditions.
Andrey Ganopolski
Clim. Past, 20, 151–185, https://doi.org/10.5194/cp-20-151-2024, https://doi.org/10.5194/cp-20-151-2024, 2024
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Despite significant progress in modelling Quaternary climate dynamics, a comprehensive theory of glacial cycles is still lacking. Here, using the results of model simulations and data analysis, I present a framework of the generalized Milankovitch theory (GMT), which further advances the concept proposed by Milutin Milankovitch over a century ago. The theory explains a number of facts which were not known during Milankovitch time's, such as the 100 kyr periodicity of the late Quaternary.
Xiaoxu Shi, Martin Werner, Hu Yang, Roberta D'Agostino, Jiping Liu, Chaoyuan Yang, and Gerrit Lohmann
Clim. Past, 19, 2157–2175, https://doi.org/10.5194/cp-19-2157-2023, https://doi.org/10.5194/cp-19-2157-2023, 2023
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The Last Glacial Maximum (LGM) marks the most recent extremely cold and dry time period of our planet. Using AWI-ESM, we quantify the relative importance of Earth's orbit, greenhouse gases (GHG) and ice sheets (IS) in determining the LGM climate. Our results suggest that both GHG and IS play important roles in shaping the LGM temperature. Continental ice sheets exert a major control on precipitation, atmospheric dynamics, and the intensity of El Niño–Southern Oscillation.
Mikhail Y. Verbitsky and Michel Crucifix
Clim. Past, 19, 1793–1803, https://doi.org/10.5194/cp-19-1793-2023, https://doi.org/10.5194/cp-19-1793-2023, 2023
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Are phenomenological dynamical paleoclimate models physically similar to Nature? We demonstrated that though they may be very accurate in reproducing empirical time series, this is not sufficient to claim physical similarity with Nature until similarity parameters are considered. We suggest that the diagnostics of physical similarity should become a standard procedure before a phenomenological model can be utilized for interpretations of historical records or future predictions.
Nathaelle Bouttes, Fanny Lhardy, Aurélien Quiquet, Didier Paillard, Hugues Goosse, and Didier M. Roche
Clim. Past, 19, 1027–1042, https://doi.org/10.5194/cp-19-1027-2023, https://doi.org/10.5194/cp-19-1027-2023, 2023
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The last deglaciation is a period of large warming from 21 000 to 9000 years ago, concomitant with ice sheet melting. Here, we evaluate the impact of different ice sheet reconstructions and different processes linked to their changes. Changes in bathymetry and coastlines, although not often accounted for, cannot be neglected. Ice sheet melt results in freshwater into the ocean with large effects on ocean circulation, but the timing cannot explain the observed abrupt climate changes.
Maria Vittoria Guarino, Louise C. Sime, Rachel Diamond, Jeff Ridley, and David Schroeder
Clim. Past, 19, 865–881, https://doi.org/10.5194/cp-19-865-2023, https://doi.org/10.5194/cp-19-865-2023, 2023
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We investigate the response of the atmosphere, ocean, and ice domains to the release of a large volume of glacial meltwaters thought to have occurred during the Last Interglacial period. We show that the signal that originated in the North Atlantic travels over great distances across the globe. It modifies the ocean gyre circulation in the Northern Hemisphere as well as the belt of westerly winds in the Southern Hemisphere, with consequences for Antarctic sea ice.
Marie Sicard, Masa Kageyama, Sylvie Charbit, Pascale Braconnot, and Jean-Baptiste Madeleine
Clim. Past, 18, 607–629, https://doi.org/10.5194/cp-18-607-2022, https://doi.org/10.5194/cp-18-607-2022, 2022
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The Last Interglacial (129–116 ka) is characterised by an increased summer insolation over the Arctic region, which leads to a strong temperature rise. The aim of this study is to identify and quantify the main processes and feedback causing this Arctic warming. Using the IPSL-CM6A-LR model, we investigate changes in the energy budget relative to the pre-industrial period. We highlight the crucial role of Arctic sea ice cover, ocean and clouds on the Last Interglacial Arctic warming.
Andre Berger
Clim. Past, 17, 1727–1733, https://doi.org/10.5194/cp-17-1727-2021, https://doi.org/10.5194/cp-17-1727-2021, 2021
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This paper stresses the original contributions of Milankovitch related to his caloric seasons and his climate model giving the caloric seasons a climatological meaning.
Andreas Plach, Bo M. Vinther, Kerim H. Nisancioglu, Sindhu Vudayagiri, and Thomas Blunier
Clim. Past, 17, 317–330, https://doi.org/10.5194/cp-17-317-2021, https://doi.org/10.5194/cp-17-317-2021, 2021
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In light of recent large-scale melting of the Greenland ice sheet
(GrIS), e.g., in the summer of 2012 several days with surface melt
on the entire ice sheet (including elevations above 3000 m), we use
computer simulations to estimate the amount of melt during a
warmer-than-present period of the past. Our simulations show more
extensive melt than today. This is important for the interpretation of
ice cores which are used to reconstruct the evolution of the ice sheet
and the climate.
Chetankumar Jalihal, Joyce Helena Catharina Bosmans, Jayaraman Srinivasan, and Arindam Chakraborty
Clim. Past, 15, 449–462, https://doi.org/10.5194/cp-15-449-2019, https://doi.org/10.5194/cp-15-449-2019, 2019
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Insolation is thought to drive monsoons on orbital timescales. We find that insolation can be a trigger for changes in precipitation, but surface energy and vertical stability play an important role too. These feedbacks are found to be dominant over oceans and can even counter the insolation forcing, thus leading to a land–sea differential response in precipitation.
Rajarshi Roychowdhury and Robert DeConto
Clim. Past, 15, 377–388, https://doi.org/10.5194/cp-15-377-2019, https://doi.org/10.5194/cp-15-377-2019, 2019
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The climate response of the Earth to orbital forcing shows a distinct hemispheric asymmetry, and one of the reasons can be ascribed to the unequal distribution of land in the Northern Hemisphere and Southern Hemisphere. We show that a land asymmetry effect (LAE) exists, and that it can be quantified. By using a GCM with a unique geographic setup, we illustrate that there are far-field influences of global geography that moderate or accentuate the Earth's response to orbital forcing.
Silvana Ramos Buarque and David Salas y Melia
Clim. Past, 14, 1707–1725, https://doi.org/10.5194/cp-14-1707-2018, https://doi.org/10.5194/cp-14-1707-2018, 2018
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The link between the surface mass balance components of the Greenland Ice Sheet and both phases of the NAO is examined under preindustrial and warmer and colder climates of the last interglacial from simulations performed with CNRM-CM5.2. Accumulation in south Greenland is correlated with positive (negative) phases of the NAO in a warm (cold) climate. Melting under a warm (cold) climate is correlated with the negative (positive) phase of the NAO in north and northeast Greenland (at the margins).
Andreas Plach, Kerim H. Nisancioglu, Sébastien Le clec'h, Andreas Born, Petra M. Langebroek, Chuncheng Guo, Michael Imhof, and Thomas F. Stocker
Clim. Past, 14, 1463–1485, https://doi.org/10.5194/cp-14-1463-2018, https://doi.org/10.5194/cp-14-1463-2018, 2018
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The Greenland ice sheet is a huge frozen water reservoir which is crucial for predictions of sea level in a warming future climate. Therefore, computer models are needed to reliably simulate the melt of ice sheets. In this study, we use climate model simulations of the last period where it was warmer than today in Greenland. We test different melt models under these climatic conditions and show that the melt models show very different results under these warmer conditions.
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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The surface energy and mass balance of ice sheets strongly depends on surface albedo. Here, using an Earth system model of intermediate complexity, we explore the role played by surface albedo for the simulation of glacial cycles. We show that the evolution of the Northern Hemisphere ice sheets over the last glacial cycle is very sensitive to the parameterization of snow grain size and the effect of dust deposition on snow albedo.
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.
Louise C. Sime, Dominic Hodgson, Thomas J. Bracegirdle, Claire Allen, Bianca Perren, Stephen Roberts, and Agatha M. de Boer
Clim. Past, 12, 2241–2253, https://doi.org/10.5194/cp-12-2241-2016, https://doi.org/10.5194/cp-12-2241-2016, 2016
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Latitudinal shifts in the Southern Ocean westerly wind jet could explain large observed changes in the glacial to interglacial ocean CO2 inventory. However there is considerable disagreement in modelled deglacial-warming jet shifts. Here multi-model output is used to show that expansion of sea ice during the glacial period likely caused a slight poleward shift and intensification in the westerly wind jet. Issues with model representation of the winds caused much of the previous disagreement.
M. Stärz, G. Lohmann, and G. Knorr
Clim. Past, 12, 151–170, https://doi.org/10.5194/cp-12-151-2016, https://doi.org/10.5194/cp-12-151-2016, 2016
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In order to account for coupled climate-soil processes, we developed a soil scheme which is asynchronously coupled to an earth system model. We tested the scheme and found additional warming for a relatively warm climate (mid-Holocene), and extra cooling for a colder (Last Glacial Maximum) than preindustrial climate. These findings indicate a relatively strong positive soil feedback to climate, which may help to reduce model-data discrepancies for the climate of the geological past.
J. H. C. Bosmans, F. J. Hilgen, E. Tuenter, and L. J. Lourens
Clim. Past, 11, 1335–1346, https://doi.org/10.5194/cp-11-1335-2015, https://doi.org/10.5194/cp-11-1335-2015, 2015
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Our study shows that the influence of obliquity (the tilt of Earth's rotational axis) can be explained through changes in the insolation gradient across the tropics. This explanation is fundamentally different from high-latitude mechanisms that were previously often inferred to explain obliquity signals in low-latitude paleoclimate records, for instance glacial fluctuations. Our study is based on state-of-the-art climate model experiments.
N. Sudarchikova, U. Mikolajewicz, C. Timmreck, D. O'Donnell, G. Schurgers, D. Sein, and K. Zhang
Clim. Past, 11, 765–779, https://doi.org/10.5194/cp-11-765-2015, https://doi.org/10.5194/cp-11-765-2015, 2015
F. A. Ziemen, C. B. Rodehacke, and U. Mikolajewicz
Clim. Past, 10, 1817–1836, https://doi.org/10.5194/cp-10-1817-2014, https://doi.org/10.5194/cp-10-1817-2014, 2014
Q. Z. Yin, U. K. Singh, A. Berger, Z. T. Guo, and M. Crucifix
Clim. Past, 10, 1645–1657, https://doi.org/10.5194/cp-10-1645-2014, https://doi.org/10.5194/cp-10-1645-2014, 2014
M. F. Loutre, T. Fichefet, H. Goosse, P. Huybrechts, H. Goelzer, and E. Capron
Clim. Past, 10, 1541–1565, https://doi.org/10.5194/cp-10-1541-2014, https://doi.org/10.5194/cp-10-1541-2014, 2014
M. Heinemann, A. Timmermann, O. Elison Timm, F. Saito, and A. Abe-Ouchi
Clim. Past, 10, 1567–1579, https://doi.org/10.5194/cp-10-1567-2014, https://doi.org/10.5194/cp-10-1567-2014, 2014
N. Korhonen, A. Venäläinen, H. Seppä, and H. Järvinen
Clim. Past, 10, 1489–1500, https://doi.org/10.5194/cp-10-1489-2014, https://doi.org/10.5194/cp-10-1489-2014, 2014
M.-N. Woillez, G. Levavasseur, A.-L. Daniau, M. Kageyama, D. H. Urrego, M.-F. Sánchez-Goñi, and V. Hanquiez
Clim. Past, 10, 1165–1182, https://doi.org/10.5194/cp-10-1165-2014, https://doi.org/10.5194/cp-10-1165-2014, 2014
C. Contoux, A. Jost, G. Ramstein, P. Sepulchre, G. Krinner, and M. Schuster
Clim. Past, 9, 1417–1430, https://doi.org/10.5194/cp-9-1417-2013, https://doi.org/10.5194/cp-9-1417-2013, 2013
D. Xiao, P. Zhao, Y. Wang, and X. Zhou
Clim. Past, 9, 735–747, https://doi.org/10.5194/cp-9-735-2013, https://doi.org/10.5194/cp-9-735-2013, 2013
E. J. Stone, D. J. Lunt, J. D. Annan, and J. C. Hargreaves
Clim. Past, 9, 621–639, https://doi.org/10.5194/cp-9-621-2013, https://doi.org/10.5194/cp-9-621-2013, 2013
Y. Chavaillaz, F. Codron, and M. Kageyama
Clim. Past, 9, 517–524, https://doi.org/10.5194/cp-9-517-2013, https://doi.org/10.5194/cp-9-517-2013, 2013
J. Majorowicz, J. Safanda, and K. Osadetz
Clim. Past, 8, 667–682, https://doi.org/10.5194/cp-8-667-2012, https://doi.org/10.5194/cp-8-667-2012, 2012
A. Ganopolski and R. Calov
Clim. Past, 7, 1415–1425, https://doi.org/10.5194/cp-7-1415-2011, https://doi.org/10.5194/cp-7-1415-2011, 2011
T. Y. M. Konijnendijk, S. L. Weber, E. Tuenter, and M. van Weele
Clim. Past, 7, 635–648, https://doi.org/10.5194/cp-7-635-2011, https://doi.org/10.5194/cp-7-635-2011, 2011
D. M. Roche, H. Renssen, D. Paillard, and G. Levavasseur
Clim. Past, 7, 591–602, https://doi.org/10.5194/cp-7-591-2011, https://doi.org/10.5194/cp-7-591-2011, 2011
N. Fischer and J. H. Jungclaus
Clim. Past, 6, 155–168, https://doi.org/10.5194/cp-6-155-2010, https://doi.org/10.5194/cp-6-155-2010, 2010
S. Bonelli, S. Charbit, M. Kageyama, M.-N. Woillez, G. Ramstein, C. Dumas, and A. Quiquet
Clim. Past, 5, 329–345, https://doi.org/10.5194/cp-5-329-2009, https://doi.org/10.5194/cp-5-329-2009, 2009
Q. Z. Yin, A. Berger, and M. Crucifix
Clim. Past, 5, 229–243, https://doi.org/10.5194/cp-5-229-2009, https://doi.org/10.5194/cp-5-229-2009, 2009
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