Articles | Volume 12, issue 9
https://doi.org/10.5194/cp-12-1829-2016
© Author(s) 2016. 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-12-1829-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
08 Sep 2016
Research article |
| 08 Sep 2016
The effect of greenhouse gas concentrations and ice sheets on the glacial AMOC in a coupled climate model
Marlene Klockmann
CORRESPONDING AUTHOR
Max Planck Institute for Meteorology, Hamburg, Germany
International Max Planck Research School on Earth System Modelling, Hamburg, Germany
Uwe Mikolajewicz
Max Planck Institute for Meteorology, Hamburg, Germany
Jochem Marotzke
Max Planck Institute for Meteorology, Hamburg, Germany
Related authors
Marlene Klockmann, Udo von Toussaint, and Eduardo Zorita
Geosci. Model Dev., 17, 1765–1787, https://doi.org/10.5194/gmd-17-1765-2024, https://doi.org/10.5194/gmd-17-1765-2024, 2024
Short summary
Short summary
Reconstructions of climate variability before the observational period rely on climate proxies and sophisticated statistical models to link the proxy information and climate variability. Existing models tend to underestimate the true magnitude of variability, especially if the proxies contain non-climatic noise. We present and test a promising new framework for climate-index reconstructions, based on Gaussian processes, which reconstructs robust variability estimates from noisy and sparse data.
Zeguo Zhang, Sebastian Wagner, Marlene Klockmann, and Eduardo Zorita
Clim. Past, 18, 2643–2668, https://doi.org/10.5194/cp-18-2643-2022, https://doi.org/10.5194/cp-18-2643-2022, 2022
Short summary
Short summary
A bidirectional long short-term memory (LSTM) neural network was employed for the first time for past temperature field reconstructions. The LSTM method tested in our experiments using a limited calibration and validation dataset shows worse reconstruction skills compared to traditional reconstruction methods. However, a certain degree of reconstruction performance achieved by the nonlinear LSTM method shows that skill can be achieved even when using small samples with limited datasets.
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
Short summary
Short summary
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.
Malena Andernach, Marie-Luise Kapsch, and Uwe Mikolajewicz
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2024-24, https://doi.org/10.5194/esd-2024-24, 2024
Preprint under review for ESD
Short summary
Short summary
Using a comprehensive set of simulations with the Max Planck Institute for Meteorology Earth System Model, we disentangle and quantify the impacts of a disintegrated Greenland Ice Sheet on the global climate, including the deep ocean. We find that most of the climate response is driven by Greenland’s lower elevation and enhanced by changed surface-properties, although regional differences exist. The altered climate conditions constrain a potential ice-sheet regrowth to high-bedrock elevations.
Katharina D. Six, Uwe Mikolajewicz, and Gerhard Schmiedl
Clim. Past, 20, 1785–1816, https://doi.org/10.5194/cp-20-1785-2024, https://doi.org/10.5194/cp-20-1785-2024, 2024
Short summary
Short summary
We use a physical and biogeochemical ocean model of the Mediterranean Sea to obtain a picture of the Last Glacial Maximum. The shallowing of the Strait of Gibraltar leads to a shallower pycnocline and more efficient nutrient export. Consistent with the sediment data, an increase in organic matter deposition is simulated, although this is based on lower biological production. This unexpected but plausible result resolves the apparent contradiction between planktonic and benthic proxy data.
Uwe Mikolajewicz, Marie-Luise Kapsch, Clemens Schannwell, Katharina D. Six, Florian A. Ziemen, Meike Bagge, Jean-Philippe Baudouin, Olga Erokhina, Veronika Gayler, Volker Klemann, Virna L. Meccia, Anne Mouchet, and Thomas Riddick
Clim. Past Discuss., https://doi.org/10.5194/cp-2024-55, https://doi.org/10.5194/cp-2024-55, 2024
Revised manuscript under review for CP
Short summary
Short summary
A fully coupled atmosphere-ocean-ice sheet-solid earth model was applied to simulate the time from the last glacial maximum to the preindustrial. The model simulations are compared to proxy data. During the glacial and deglaciation the model simulates several abrupt changes in North Atlantic climate. The underlying meachanisms are analysed and described.
Elisa Ziegler, Nils Weitzel, Jean-Philippe Baudouin, Marie-Luise Kapsch, Uwe Mikolajewicz, Lauren Gregoire, Ruza Ivanovic, Paul J. Valdes, Christian Wirths, and Kira Rehfeld
EGUsphere, https://doi.org/10.5194/egusphere-2024-1396, https://doi.org/10.5194/egusphere-2024-1396, 2024
Short summary
Short summary
During the Last Deglaciation global surface temperature rose by about 4–7 degrees over several millennia. We show that changes of year-to-year up to century-to-century fluctuations of temperature and precipitation during the Deglaciation were mostly larger than during either the preceding or succeeding more stable periods in fifteen climate model simulations. The analysis demonstrates how ice sheets, meltwater and volcanism influence simulated variability to inform future simulation protocols.
Bjorn Stevens, Stefan Adami, Tariq Ali, Hartwig Anzt, Zafer Aslan, Sabine Attinger, Jaana Bäck, Johanna Baehr, Peter Bauer, Natacha Bernier, Bob Bishop, Hendryk Bockelmann, Sandrine Bony, Guy Brasseur, David N. Bresch, Sean Breyer, Gilbert Brunet, Pier Luigi Buttigieg, Junji Cao, Christelle Castet, Yafang Cheng, Ayantika Dey Choudhury, Deborah Coen, Susanne Crewell, Atish Dabholkar, Qing Dai, Francisco Doblas-Reyes, Dale Durran, Ayoub El Gaidi, Charlie Ewen, Eleftheria Exarchou, Veronika Eyring, Florencia Falkinhoff, David Farrell, Piers M. Forster, Ariane Frassoni, Claudia Frauen, Oliver Fuhrer, Shahzad Gani, Edwin Gerber, Debra Goldfarb, Jens Grieger, Nicolas Gruber, Wilco Hazeleger, Rolf Herken, Chris Hewitt, Torsten Hoefler, Huang-Hsiung Hsu, Daniela Jacob, Alexandra Jahn, Christian Jakob, Thomas Jung, Christopher Kadow, In-Sik Kang, Sarah Kang, Karthik Kashinath, Katharina Kleinen-von Königslöw, Daniel Klocke, Uta Kloenne, Milan Klöwer, Chihiro Kodama, Stefan Kollet, Tobias Kölling, Jenni Kontkanen, Steve Kopp, Michal Koran, Markku Kulmala, Hanna Lappalainen, Fakhria Latifi, Bryan Lawrence, June Yi Lee, Quentin Lejeun, Christian Lessig, Chao Li, Thomas Lippert, Jürg Luterbacher, Pekka Manninen, Jochem Marotzke, Satoshi Matsouoka, Charlotte Merchant, Peter Messmer, Gero Michel, Kristel Michielsen, Tomoki Miyakawa, Jens Müller, Ramsha Munir, Sandeep Narayanasetti, Ousmane Ndiaye, Carlos Nobre, Achim Oberg, Riko Oki, Tuba Özkan-Haller, Tim Palmer, Stan Posey, Andreas Prein, Odessa Primus, Mike Pritchard, Julie Pullen, Dian Putrasahan, Johannes Quaas, Krishnan Raghavan, Venkatachalam Ramaswamy, Markus Rapp, Florian Rauser, Markus Reichstein, Aromar Revi, Sonakshi Saluja, Masaki Satoh, Vera Schemann, Sebastian Schemm, Christina Schnadt Poberaj, Thomas Schulthess, Cath Senior, Jagadish Shukla, Manmeet Singh, Julia Slingo, Adam Sobel, Silvina Solman, Jenna Spitzer, Philip Stier, Thomas Stocker, Sarah Strock, Hang Su, Petteri Taalas, John Taylor, Susann Tegtmeier, Georg Teutsch, Adrian Tompkins, Uwe Ulbrich, Pier-Luigi Vidale, Chien-Ming Wu, Hao Xu, Najibullah Zaki, Laure Zanna, Tianjun Zhou, and Florian Ziemen
Earth Syst. Sci. Data, 16, 2113–2122, https://doi.org/10.5194/essd-16-2113-2024, https://doi.org/10.5194/essd-16-2113-2024, 2024
Short summary
Short summary
To manage Earth in the Anthropocene, new tools, new institutions, and new forms of international cooperation will be required. Earth Virtualization Engines is proposed as an international federation of centers of excellence to empower all people to respond to the immense and urgent challenges posed by climate change.
Nils Weitzel, Heather Andres, Jean-Philippe Baudouin, Marie-Luise Kapsch, Uwe Mikolajewicz, Lukas Jonkers, Oliver Bothe, Elisa Ziegler, Thomas Kleinen, André Paul, and Kira Rehfeld
Clim. Past, 20, 865–890, https://doi.org/10.5194/cp-20-865-2024, https://doi.org/10.5194/cp-20-865-2024, 2024
Short summary
Short summary
The ability of climate models to faithfully reproduce past warming episodes is a valuable test considering potentially large future warming. We develop a new method to compare simulations of the last deglaciation with temperature reconstructions. We find that reconstructions differ more between regions than simulations, potentially due to deficiencies in the simulation design, models, or reconstructions. Our work is a promising step towards benchmarking simulations of past climate transitions.
Brooke Snoll, Ruza Ivanovic, Lauren Gregoire, Sam Sherriff-Tadano, Laurie Menviel, Takashi Obase, Ayako Abe-Ouchi, Nathaelle Bouttes, Chengfei He, Feng He, Marie Kapsch, Uwe Mikolajewicz, Juan Muglia, and Paul Valdes
Clim. Past, 20, 789–815, https://doi.org/10.5194/cp-20-789-2024, https://doi.org/10.5194/cp-20-789-2024, 2024
Short summary
Short summary
Geological records show rapid climate change throughout the recent deglaciation. The drivers of these changes are still misunderstood but are often attributed to shifts in the Atlantic Ocean circulation from meltwater input. A cumulative effort to understand these processes prompted numerous simulations of this period. We use these to explain the chain of events and our collective ability to simulate them. The results demonstrate the importance of the meltwater amount used in the simulation.
Marlene Klockmann, Udo von Toussaint, and Eduardo Zorita
Geosci. Model Dev., 17, 1765–1787, https://doi.org/10.5194/gmd-17-1765-2024, https://doi.org/10.5194/gmd-17-1765-2024, 2024
Short summary
Short summary
Reconstructions of climate variability before the observational period rely on climate proxies and sophisticated statistical models to link the proxy information and climate variability. Existing models tend to underestimate the true magnitude of variability, especially if the proxies contain non-climatic noise. We present and test a promising new framework for climate-index reconstructions, based on Gaussian processes, which reconstructs robust variability estimates from noisy and sparse data.
Takashi Obase, Laurie Menviel, Ayako Abe-Ouchi, Tristan Vadsaria, Ruza Ivanovic, Brooke Snoll, Sam Sherriff-Tadano, Paul Valdes, Lauren Gregoire, Marie-Luise Kapsch, Uwe Mikolajewicz, Nathaelle Bouttes, Didier Roche, Fanny Lhardy, Chengfei He, Bette Otto-Bliesner, Zhengyu Liu, and Wing-Le Chan
Clim. Past Discuss., https://doi.org/10.5194/cp-2023-86, https://doi.org/10.5194/cp-2023-86, 2023
Revised manuscript under review for CP
Short summary
Short summary
This study analyses transient simulations of the last deglaciation performed by six climate models to understand the processes driving southern high latitude temperature changes. We find that atmospheric CO2 changes and AMOC changes are the primary drivers of the major warming and cooling during the middle stage of the deglaciation. The multi-model analysis highlights the model’s sensitivity of CO2, AMOC to meltwater, and the meltwater history on temperature changes in southern high latitudes.
Cathy Hohenegger, Peter Korn, Leonidas Linardakis, René Redler, Reiner Schnur, Panagiotis Adamidis, Jiawei Bao, Swantje Bastin, Milad Behravesh, Martin Bergemann, Joachim Biercamp, Hendryk Bockelmann, Renate Brokopf, Nils Brüggemann, Lucas Casaroli, Fatemeh Chegini, George Datseris, Monika Esch, Geet George, Marco Giorgetta, Oliver Gutjahr, Helmuth Haak, Moritz Hanke, Tatiana Ilyina, Thomas Jahns, Johann Jungclaus, Marcel Kern, Daniel Klocke, Lukas Kluft, Tobias Kölling, Luis Kornblueh, Sergey Kosukhin, Clarissa Kroll, Junhong Lee, Thorsten Mauritsen, Carolin Mehlmann, Theresa Mieslinger, Ann Kristin Naumann, Laura Paccini, Angel Peinado, Divya Sri Praturi, Dian Putrasahan, Sebastian Rast, Thomas Riddick, Niklas Roeber, Hauke Schmidt, Uwe Schulzweida, Florian Schütte, Hans Segura, Radomyra Shevchenko, Vikram Singh, Mia Specht, Claudia Christine Stephan, Jin-Song von Storch, Raphaela Vogel, Christian Wengel, Marius Winkler, Florian Ziemen, Jochem Marotzke, and Bjorn Stevens
Geosci. Model Dev., 16, 779–811, https://doi.org/10.5194/gmd-16-779-2023, https://doi.org/10.5194/gmd-16-779-2023, 2023
Short summary
Short summary
Models of the Earth system used to understand climate and predict its change typically employ a grid spacing of about 100 km. Yet, many atmospheric and oceanic processes occur on much smaller scales. In this study, we present a new model configuration designed for the simulation of the components of the Earth system and their interactions at kilometer and smaller scales, allowing an explicit representation of the main drivers of the flow of energy and matter by solving the underlying equations.
Clemens Schannwell, Uwe Mikolajewicz, Florian Ziemen, and Marie-Luise Kapsch
Clim. Past, 19, 179–198, https://doi.org/10.5194/cp-19-179-2023, https://doi.org/10.5194/cp-19-179-2023, 2023
Short summary
Short summary
Heinrich-type ice-sheet surges are recurring events over the course of the last glacial cycle during which large numbers of icebergs are discharged from the Laurentide ice sheet into the ocean. These events alter the evolution of the global climate. Here, we use model simulations of the Laurentide ice sheet to identify and quantify the importance of various climate and ice-sheet parameters for the simulated surge cycle.
Zeguo Zhang, Sebastian Wagner, Marlene Klockmann, and Eduardo Zorita
Clim. Past, 18, 2643–2668, https://doi.org/10.5194/cp-18-2643-2022, https://doi.org/10.5194/cp-18-2643-2022, 2022
Short summary
Short summary
A bidirectional long short-term memory (LSTM) neural network was employed for the first time for past temperature field reconstructions. The LSTM method tested in our experiments using a limited calibration and validation dataset shows worse reconstruction skills compared to traditional reconstruction methods. However, a certain degree of reconstruction performance achieved by the nonlinear LSTM method shows that skill can be achieved even when using small samples with limited datasets.
Tim Rohrschneider, Johanna Baehr, Veit Lüschow, Dian Putrasahan, and Jochem Marotzke
Ocean Sci., 18, 979–996, https://doi.org/10.5194/os-18-979-2022, https://doi.org/10.5194/os-18-979-2022, 2022
Short summary
Short summary
This paper presents an analysis of wind sensitivity experiments in order to provide insight into the wind forcing dependence of the AMOC by understanding the behavior of its depth scale(s).
Lennart Ramme and Jochem Marotzke
Clim. Past, 18, 759–774, https://doi.org/10.5194/cp-18-759-2022, https://doi.org/10.5194/cp-18-759-2022, 2022
Short summary
Short summary
After the Marinoan snowball Earth, the climate warmed rapidly due to enhanced greenhouse conditions, and the freshwater inflow of melting glaciers caused a strong stratification of the ocean. Our climate simulations reveal a potentially only moderate global temperature increase and a break-up of the stratification within just a few thousand years. The findings give insights into the environmental conditions relevant for the geological and biological evolution during that time.
Katharina Dorothea Six and Uwe Mikolajewicz
Biogeosciences Discuss., https://doi.org/10.5194/bg-2022-27, https://doi.org/10.5194/bg-2022-27, 2022
Preprint withdrawn
Short summary
Short summary
We developed a global ocean biogeochemical model with a zoom on the Benguela upwelling system. We show that the high spatial resolution is necessary to capture long-term trends of oxygen of the recent past. The regional anthropogenic carbon uptake over the last century is lower than compared to a coarser resolution ocean model as used in Earth system models. This suggests that, at least for some regions, the changes projected by these Earth system models are associated with high uncertainty.
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
Short summary
Short summary
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.
Marie-Luise Kapsch, Uwe Mikolajewicz, Florian A. Ziemen, Christian B. Rodehacke, and Clemens Schannwell
The Cryosphere, 15, 1131–1156, https://doi.org/10.5194/tc-15-1131-2021, https://doi.org/10.5194/tc-15-1131-2021, 2021
Xavier Fettweis, Stefan Hofer, Uta Krebs-Kanzow, Charles Amory, Teruo Aoki, Constantijn J. Berends, Andreas Born, Jason E. Box, Alison Delhasse, Koji Fujita, Paul Gierz, Heiko Goelzer, Edward Hanna, Akihiro Hashimoto, Philippe Huybrechts, Marie-Luise Kapsch, Michalea D. King, Christoph Kittel, Charlotte Lang, Peter L. Langen, Jan T. M. Lenaerts, Glen E. Liston, Gerrit Lohmann, Sebastian H. Mernild, Uwe Mikolajewicz, Kameswarrao Modali, Ruth H. Mottram, Masashi Niwano, Brice Noël, Jonathan C. Ryan, Amy Smith, Jan Streffing, Marco Tedesco, Willem Jan van de Berg, Michiel van den Broeke, Roderik S. W. van de Wal, Leo van Kampenhout, David Wilton, Bert Wouters, Florian Ziemen, and Tobias Zolles
The Cryosphere, 14, 3935–3958, https://doi.org/10.5194/tc-14-3935-2020, https://doi.org/10.5194/tc-14-3935-2020, 2020
Short summary
Short summary
We evaluated simulated Greenland Ice Sheet surface mass balance from 5 kinds of models. While the most complex (but expensive to compute) models remain the best, the faster/simpler models also compare reliably with observations and have biases of the same order as the regional models. Discrepancies in the trend over 2000–2012, however, suggest that large uncertainties remain in the modelled future SMB changes as they are highly impacted by the meltwater runoff biases over the current climate.
Suzanne Alice Ghislaine Leroy, Klaus Arpe, Uwe Mikolajewicz, and Jing Wu
Clim. Past, 16, 2039–2054, https://doi.org/10.5194/cp-16-2039-2020, https://doi.org/10.5194/cp-16-2039-2020, 2020
Short summary
Short summary
The biodiversity of temperate deciduous trees in eastern Asia is greater than in Europe. During the peak of the last ice age, their distribution was obtained based on pollen data literature. A climate model, after validation on the present, was used to calculate the potential distribution of such trees in the past. It shows that the shift of the tree belt was only 2° latitude to the south. Moreover, greater population connectivity was shown for the Yellow Sea and southern Himalayas.
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
Short summary
Short summary
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.
Flavio Lehner, Clara Deser, Nicola Maher, Jochem Marotzke, Erich M. Fischer, Lukas Brunner, Reto Knutti, and Ed Hawkins
Earth Syst. Dynam., 11, 491–508, https://doi.org/10.5194/esd-11-491-2020, https://doi.org/10.5194/esd-11-491-2020, 2020
Short summary
Short summary
Projections of climate change are uncertain because climate models are imperfect, future greenhouse gases emissions are unknown and climate is to some extent chaotic. To partition and understand these sources of uncertainty and make the best use of climate projections, large ensembles with multiple climate models are needed. Such ensembles now exist in a public data archive. We provide several novel applications focused on global and regional temperature and precipitation projections.
Moritz Mathis and Uwe Mikolajewicz
Ocean Sci., 16, 167–193, https://doi.org/10.5194/os-16-167-2020, https://doi.org/10.5194/os-16-167-2020, 2020
Short summary
Short summary
In a strong global warming scenario, declining nutrient concentrations of Atlantic water masses flushing the NWES lead to a reduction in the biological productivity on the shelf. We show that meltwater discharge from the Greenland ice sheet induces a change in the subpolar ocean circulation, resulting in a nutrient increase of deeper Atlantic water masses. These are mixed up at the shelf break and spread over the shelf, mitigating both the expected nutrient decline and productivity reduction.
Andreas Lang and Uwe Mikolajewicz
Ocean Sci., 15, 651–668, https://doi.org/10.5194/os-15-651-2019, https://doi.org/10.5194/os-15-651-2019, 2019
Short summary
Short summary
Here we investigate the occurrence of extreme storm surges in the southern German Bight and their associated large-scale forcing mechanisms using climate model simulations covering the last 1000 years. We find that extreme storm surges are characterized by a large internal variability that masks potential links to external climate forcing or background sea level fluctuations; existing estimates of extreme sea levels based on short data records thus fail to account for their full variability.
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
Short summary
Short summary
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.
Virna Loana Meccia and Uwe Mikolajewicz
Geosci. Model Dev., 11, 4677–4692, https://doi.org/10.5194/gmd-11-4677-2018, https://doi.org/10.5194/gmd-11-4677-2018, 2018
Thomas Riddick, Victor Brovkin, Stefan Hagemann, and Uwe Mikolajewicz
Geosci. Model Dev., 11, 4291–4316, https://doi.org/10.5194/gmd-11-4291-2018, https://doi.org/10.5194/gmd-11-4291-2018, 2018
Short summary
Short summary
During the Last Glacial Maximum, many rivers were blocked by the presence of large ice sheets and thus found new routes to the sea. This resulted in changes in the pattern of freshwater discharge into the oceans and thus would have significantly affected ocean circulation. Also, rivers found routes across the vast exposed continental shelves to the lower coastlines of that time. We propose a model for such changes in river routing suitable for use in wider models of the last glacial cycle.
Uwe Mikolajewicz, Florian Ziemen, Guido Cioni, Martin Claussen, Klaus Fraedrich, Marvin Heidkamp, Cathy Hohenegger, Diego Jimenez de la Cuesta, Marie-Luise Kapsch, Alexander Lemburg, Thorsten Mauritsen, Katharina Meraner, Niklas Röber, Hauke Schmidt, Katharina D. Six, Irene Stemmler, Talia Tamarin-Brodsky, Alexander Winkler, Xiuhua Zhu, and Bjorn Stevens
Earth Syst. Dynam., 9, 1191–1215, https://doi.org/10.5194/esd-9-1191-2018, https://doi.org/10.5194/esd-9-1191-2018, 2018
Short summary
Short summary
Model experiments show that changing the sense of Earth's rotation has relatively little impact on the globally and zonally averaged energy budgets but leads to large shifts in continental climates and patterns of precipitation. The retrograde world is greener as the desert area shrinks. Deep water formation shifts from the North Atlantic to the North Pacific with subsequent changes in ocean overturning. Over large areas of the Indian Ocean, cyanobacteria dominate over bulk phytoplankton.
Valerie Menke, Werner Ehrmann, Yvonne Milker, Swaantje Brzelinski, Jürgen Möbius, Uwe Mikolajewicz, Bernd Zolitschka, Karin Zonneveld, Kay Christian Emeis, and Gerhard Schmiedl
Clim. Past Discuss., https://doi.org/10.5194/cp-2017-139, https://doi.org/10.5194/cp-2017-139, 2017
Preprint withdrawn
Short summary
Short summary
This study examines changes in the marine ecosystem during the past 1300 years in the Gulf of Taranto (Italy) to unravel natural and anthropogenic forcing. Our data suggest, that processes at the sea floor are linked to the North Atlantic Oscillation (NAO) and the Atlantic Multidecadal Oscillation. During the past 200 years, the effects of rising northern hemisphere temperature and increasing anthropogenic activity enhanced nutrient and organic matter fluxes leading to more eutrophic conditions.
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
Short summary
Short summary
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.
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
M. Gröger, E. Maier-Reimer, U. Mikolajewicz, A. Moll, and D. Sein
Biogeosciences, 10, 3767–3792, https://doi.org/10.5194/bg-10-3767-2013, https://doi.org/10.5194/bg-10-3767-2013, 2013
P. Bakker, E. J. Stone, S. Charbit, M. Gröger, U. Krebs-Kanzow, S. P. Ritz, V. Varma, V. Khon, D. J. Lunt, U. Mikolajewicz, M. Prange, H. Renssen, B. Schneider, and M. Schulz
Clim. Past, 9, 605–619, https://doi.org/10.5194/cp-9-605-2013, https://doi.org/10.5194/cp-9-605-2013, 2013
S. Tietsche, D. Notz, J. H. Jungclaus, and J. Marotzke
Ocean Sci., 9, 19–36, https://doi.org/10.5194/os-9-19-2013, https://doi.org/10.5194/os-9-19-2013, 2013
Related subject area
Subject: Ocean Dynamics | Archive: Modelling only | Timescale: Pleistocene
Glacial AMOC shoaling despite vigorous tidal dissipation: vertical stratification matters
Impact of ice sheet meltwater fluxes on the climate evolution at the onset of the Last Interglacial
The impacts of deglacial meltwater forcing on the South Atlantic Ocean deep circulation since the Last Glacial Maximum
Yugeng Chen, Pengyang Song, Xianyao Chen, and Gerrit Lohmann
Clim. Past, 20, 2001–2015, https://doi.org/10.5194/cp-20-2001-2024, https://doi.org/10.5194/cp-20-2001-2024, 2024
Short summary
Short summary
Our study examines the Atlantic Meridional Overturning Circulation (AMOC) during the Last Glacial Maximum (LGM), a period with higher tidal dissipation. Despite increased tidal mixing, our model simulations show that the AMOC remained relatively shallow, consistent with paleoproxy data and resolving previous inconsistencies between proxy data and model simulations. This research highlights the importance of strong ocean stratification during the LGM and its interaction with tidal mixing.
Heiko Goelzer, Philippe Huybrechts, Marie-France Loutre, and Thierry Fichefet
Clim. Past, 12, 1721–1737, https://doi.org/10.5194/cp-12-1721-2016, https://doi.org/10.5194/cp-12-1721-2016, 2016
Short summary
Short summary
We have modelled the climate evolution from 135 to 120 kyr BP with an Earth system model to study the onset of the Last Interglacial warm period. Ice sheet changes and associated freshwater fluxes in both hemispheres constitute an important forcing in the simulations. Freshwater fluxes from the melting Antarctic ice sheet are found to lead to an oceanic cold event in the Southern Ocean as evidenced in some ocean sediment cores, which may be used to constrain the timing of ice sheet retreat.
J. M. Marson, I. Wainer, M. M. Mata, and Z. Liu
Clim. Past, 10, 1723–1734, https://doi.org/10.5194/cp-10-1723-2014, https://doi.org/10.5194/cp-10-1723-2014, 2014
Cited articles
Abe-Ouchi, A., Saito, F., Kageyama, M., Braconnot, P., Harrison, S. P., Lambeck, K., Otto-Bliesner, B. L., Peltier, W. R., Tarasov, L., Peterschmitt, J.-Y., and Takahashi, K.: Ice-sheet configuration in the CMIP5/PMIP3 Last Glacial Maximum experiments, Geosci. Model Dev., 8, 3621–3637, https://doi.org/10.5194/gmd-8-3621-2015, 2015.
Adkins, J. F.: The role of deep ocean circulation in setting glacial climates, Paleoceanography, 28, 539–561, 2013.
Adkins, J. F., McIntyre, K., and Schrag, D. P.: The Salinity, Temperature, and δ18O of the Glacial Deep Ocean, Science, 298, 1769–1773, 2002.
Annan, J. D. and Hargreaves, J. C.: A new global reconstruction of temperature changes at the Last Glacial Maximum, Clim. Past, 9, 367–376, https://doi.org/10.5194/cp-9-367-2013, 2013.
Argus, D. F., Peltier, W., Drummond, R., and Moore, A. W.: The Antarctica component of postglacial rebound model ICE-6G_C (VM5a) based on GPS positioning, exposure age dating of ice thicknesses, and relative sea level histories, Geophys. J. Int., 198, 537–563, 2014.
Bartlein, P., Harrison, S., Brewer, S., Connor, S., Davis, B., Gajewski, K., Guiot, J., Harrison-Prentice, T., Henderson, A., Peyron, O., Prentice, I. C., Scholze, M., Seppä, H., Shuman, B., Sugita, S., Thompson, R. S., Viau, A. E., Williams, J., and Wu, H.: Pollen-based continental climate reconstructions at 6 and 21 ka: a global synthesis, Clim. Dynam., 37, 775–802, 2011.
Böhm, E., Lippold, J., Gutjahr, M., Frank, M., Blaser, P., Antz, B., Fohlmeister, J., Frank, N., Andersen, M., and Deininger, M.: Strong and deep Atlantic meridional overturning circulation during the last glacial cycle, Nature, 517, 73–76, 2015.
Braconnot, P. and Kageyama, M.: Shortwave forcing and feedbacks in Last Glacial Maximum and Mid-Holocene PMIP3 simulations, Philos. T. R. Soc. A, 373, 20140424, https://doi.org/10.1098/rsta.2014.0424, 2015.
Braconnot, P., Otto–Bliesner, B., Harrison, S., Joussaume, S., Peterchmitt, J.-Y., Abe-Ouchi, A., Crucifix, M., Driesschaert, E., Fichefet, Th., Hewitt, C. D., Kageyama, M., Kitoh, A., Laîné, A., Loutre, M.-F., Marti, O., Merkel, U., Ramstein, G., Valdes, P., Weber, S. L., Yu, Y., and Zhao, Y.: Results of PMIP2 coupled simulations of the Mid-Holocene and Last Glacial Maximum – Part 1: experiments and large-scale features, Clim. Past, 3, 261–277, https://doi.org/10.5194/cp-3-261-2007, 2007.
Brady, E. C., Otto-Bliesner, B. L., Kay, J. E., and Rosenbloom, N.: Sensitivity to Glacial Forcing in the CCSM4, J. Climate, 26, 1901–1925, 2013.
Broccoli, A. and Manabe, S.: The influence of continental ice, atmospheric CO2, and land albedo on the climate of the last glacial maximum, Clim. Dynam., 1, 87–99, 1987.
Burke, A., Marchal, O., Bradtmiller, L. I., McManus, J. F., and François, R.: Application of an inverse method to interpret 231Pa ∕ 230Th observations from marine sediments, Paleoceanography, 26, PA1212, https://doi.org/10.1029/2010PA002022, 2011.
Curry, W. B. and Oppo, D. W.: Glacial water mass geometry and the distribution of δ13C of ΣCO2 in the western Atlantic Ocean, Paleoceanography, 20, PA1017, https://doi.org/10.1029/2004PA001021, 2005.
Duplessy, J., Shackleton, N., Fairbanks, R., Labeyrie, L., Oppo, D., and Kallel, N.: Deepwater source variations during the last climatic cycle and their impact on the global deepwater circulation, Paleoceanography, 3, 343–360, 1988.
Felzer, B., Webb III, T., and Oglesby, R. J.: The impact of ice sheets, CO2, and orbital insolation on late Quaternary climates: sensitivity experiments with a general circulation model, Quaternary Sci. Rev., 17, 507–534, 1998.
Ferrari, R., Jansen, M. F., Adkins, J. F., Burke, A., Stewart, A. L., and Thompson, A. F.: Antarctic sea ice control on ocean circulation in present and glacial climates, P. Natl. Acad. Sci. USA, 111, 8753–8758, 2014.
Frajka-Williams, E., Cunningham, S., Bryden, H., and King, B.: Variability of Antarctic Bottom Water at 24.5 N in the Atlantic, J. Geophys. Res.-Oceans, 116, C11026, https://doi.org/10.1029/2011JC007168, 2011.
Gebbie, G.: How much did glacial North Atlantic water shoal?, Paleoceanography, 29, 190–209, 2014.
Giorgetta, M. A., Jungclaus, J., Reick, C. H., Legutke, S., Bader, J., Böttinger, M., Brovkin, V., Crueger, T., Esch, M., Fieg, K., Glushak, K., Gayler, V. Haak, H., Hollweg, H.-D., Ilyina, T., Kinne, S., Kornblueh, L., Matei, D., Mauritsen, T., Mikolajewicz, U., Mueller, W., Notz, D., Pithan, F., Raddatz, T., Rast, S., Redler, R., Roeckner, E., Schmidt, H., Schnur, R., Segschneider, J., Six, K. D., Stockhause, M., Timmreck, C., Wegner, J., Widmann, H., Wieners, K.-H., Claussen, M., Marotzke, J., and Stevens, B.: Climate and carbon cycle changes from 1850 to 2100 in MPI-ESM simulations for the Coupled Model Intercomparison Project phase 5, J. Adv. Model. Earth Syst., 5, 572–597, 2013.
Hargreaves, J. C., Annan, J. D., Ohgaito, R., Paul, A., and Abe-Ouchi, A.: Skill and reliability of climate model ensembles at the Last Glacial Maximum and mid-Holocene, Clim. Past, 9, 811–823, https://doi.org/10.5194/cp-9-811-2013, 2013.
Hewitt, C. and Mitchell, J.: Radiative forcing and response of a GCM to ice age boundary conditions: cloud feedback and climate sensitivity, Clim. Dynam., 13, 821–834, 1997.
Jungclaus, J., Keenlyside, N., Botzet, M., Haak, H., Luo, J.-J., Latif, M., Marotzke, J., Mikolajewicz, U., and Roeckner, E.: Ocean Circulation and Tropical Variability in the Coupled Model ECHAM5/MPI-OM, J. Climate, 19, 3952–3972, 2006.
Jungclaus, J., Fischer, N., Haak, H., Lohmann, K., Marotzke, J., Matei, D., Mikolajewicz, U., Notz, D., and Storch, J.: Characteristics of the ocean simulations in the Max Planck Institute Ocean Model (MPIOM) the ocean component of the MPI-Earth system model, J. Adv. Model. Earth Syst., 5, 422–446, 2013.
Justino, F., Timmermann, A., Merkel, U., and Souza, E. P.: Synoptic Reorganization of Atmospheric flow during the Last Glacial Maximum, J. Climate, 18, 2826–2846, 2005.
Kim, S.-J.: The effect of atmospheric CO2 and ice sheet topography on LGM climate, Clim. Dynam., 22, 639–651, 2004.
Lambeck, K., Purcell, A., Zhao, J., and Svensson, N.-O.: The Scandinavian ice sheet: from MIS 4 to the end of the Last Glacial Maximum, Boreas, 39, 410–435, 2010.
Lippold, J., Luo, Y., Francois, R., Allen, S. E., Gherardi, J., Pichat, S., Hickey, B., and Schulz, H.: Strength and geometry of the glacial Atlantic Meridional Overturning Circulation, Nat. Geosci., 5, 813–816, 2012.
MARGO Project Members: Constraints on the magnitude and patterns of ocean cooling at the Last Glacial Maximum, Nat. Geosci., 2, 127–132, 2009.
Marotzke, J.: Climate science: A grip on ice-age ocean circulation, Nature, 485, 180–181, 2012.
Marsland, S. J., Haak, H., Jungclaus, J. H., Latif, M., and Röske, F.: The Max-Planck-Institute global ocean/sea ice model with orthogonal curvilinear coordinates, Ocean Modell., 5, 91–127, 2003.
McCarthy, G., Smeed, D., Johns, W., Frajka-Williams, E., Moat, B., Rayner, D., Baringer, M., Meinen, C., Collins, J., and Bryden, H.: Measuring the Atlantic Meridional Overturning Circulation at 26° N, Prog. Oceanogr., 130, 91–111, 2015.
McManus, J., Francois, R., Gherardi, J.-M., Keigwin, L., and Brown-Leger, S.: Collapse and rapid resumption of Atlantic meridional circulation linked to deglacial climate changes, Nature, 428, 834–837, 2004.
Mikolajewicz, U.: Modeling Mediterranean Ocean climate of the Last Glacial Maximum, Clim. Past, 7, 161–180, https://doi.org/10.5194/cp-7-161-2011, 2011.
Mikolajewicz, U. and Maier-Reimer, E.: Mixed boundary conditions in ocean general circulation models and their influence on the stability of the model's conveyor belt, J. Geophys. Res.-Oceans, 99, 22633–22644, 1994.
Miller, M., Adkins, J., Menemenlis, D., and Schodlok, M.: The role of ocean cooling in setting glacial southern source bottom water salinity, Paleoceanography, 27, PA3207, https://doi.org/10.1029/2012PA002297, 2012.
Msadek, R., Johns, W. E., Yeager, S. G., Danabasoglu, G., Delworth, T. L., and Rosati, A.: The Atlantic meridional heat transport at 26.5 N and its relationship with the MOC in the RAPID array and the GFDL and NCAR coupled models, J. Climate, 26, 4335–4356, 2013.
Muglia, J. and Schmittner, A.: Glacial Atlantic overturning increased by wind stress in climate models, Geophys. Res. Lett., 42, 9862–9868, https://doi.org/10.1002/2015GL064583, 2015.
Myhre, G., Highwood, E. J., Shine, K. P., and Stordal, F.: New estimates of radiative forcing due to well mixed greenhouse gases, Geophys. Res. Lett., 25, 2715–2718, 1998.
Notz, D., Haumann, F. A., Haak, H., Jungclaus, J. H., and Marotzke, J.: Arctic sea-ice evolution as modeled by Max Planck Institute for Meteorology's Earth system model, J. Adv. Model. Earth Syst., 5, 173–194, 2013.
Oka, A., Hasumi, H., and Abe-Ouchi, A.: The thermal threshold of the Atlantic meridional overturning circulation and its control by wind stress forcing during glacial climate, Geophys. Res. Lett., 39, L09709, https://doi.org/10.1029/2012GL051421, 2012.
Otto-Bliesner, B., Hewitt, C., Marchitto, T., Brady, E., Abe-Ouchi, A., Crucifix, M., Murakami, S., and Weber, S.: Last Glacial Maximum ocean thermohaline circulation: PMIP2 model intercomparisons and data constraints, Geophys. Res. Lett., 34, L12706, https://doi.org/10.1029/2007GL029475, 2007.
Otto-Bliesner, B. L., Brady, E. C., Clauzet, G., Tomas, R., Levis, S., and Kothavala, Z.: Last Glacial Maximum and Holocene climate in CCSM3, J. Climate, 19, 2526–2544, 2006.
Otto-Bliesner, B. L., Schneider, R., Brady, E., Kucera, M., Abe-Ouchi, A., Bard, E., Braconnot, P., Crucifix, M., Hewitt, C., Kageyama, M., Marti, O., Paul, A., Rosell-Melé, A., Waelbroeck, C., Weber, S. L., Weinelt, M., and Yu, Y.: A comparison of PMIP2 model simulations and the MARGO proxy reconstruction for tropical sea surface temperatures at last glacial maximum, Clim. Dynam., 32, 799–815, 2009.
Pausata, F. S. R., Li, C., Wettstein, J. J., Kageyama, M., and Nisancioglu, K. H.: The key role of topography in altering North Atlantic atmospheric circulation during the last glacial period, Clim. Past, 7, 1089–1101, https://doi.org/10.5194/cp-7-1089-2011, 2011.
Peltier, W.: Global glacial isostasy and the surface of the ice-age Earth: the ICE-5G (VM2) model and GRACE, Annu. Rev. Earth Planet. Sci., 32, 111–149, 2004.
Peltier, W., Argus, D., and Drummond, R.: Space geodesy constrains ice age terminal deglaciation: The global ICE-6G_C (VM5a) model, J. Geophys. Res.-Sol. Ea., 120, 450–487, 2015.
Reick, C., Raddatz, T., Brovkin, V., and Gayler, V.: Representation of natural and anthropogenic land cover change in MPI-ESM, J. Adv. Model. Earth Syst., 5, 459–482, 2013.
Schmittner, A., Urban, N. M., Shakun, J. D., Mahowald, N. M., Clark, P. U., Bartlein, P. J., Mix, A. C., and Rosell-Melé, A.: Climate Sensitivity Estimated from Temperature Reconstructions of the Last Glacial Maximum, Science, 334, 1385–1388, 2011.
Shakun, J. D., Clark, P. U., He, F., Marcott, S. A., Mix, A. C., Liu, Z., Otto-Bliesner, B., Schmittner, A., and Bard, E.: Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation, Nature, 484, 49–54, 2012.
Shin, S.-I., Liu, Z., Otto-Bliesner, B., Brady, E., Kutzbach, J., and Harrison, S.: A simulation of the Last Glacial Maximum climate using the NCAR-CCSM, Clim. Dynam., 20, 127–151, 2003.
Stevens, B., Giorgetta, M., Esch, M., Mauritsen, T., Crueger, T., Rast, S., Salzmann, M., Schmidt, H., Bader, J., Block, K., Brokopf, R., Fast, I., Kinne, S., Kornblueh, L., Lohmann, U., Pincus, R., Reichler, T., and Roeckner, E.: Atmospheric component of the MPI-M Earth System Model: ECHAM6, J. Adv. Model. Earth Syst., 5, 146–172, 2013.
Stössel, A., Notz, D., Haumann, F. A., Haak, H., Jungclaus, J., and Mikolajewicz, U.: Controlling high-latitude Southern Ocean convection in climate models, Ocean Modell., 86, 58–75, 2015.
Tarasov, L., Dyke, A. S., Neal, R. M., and Peltier, W.: A data-calibrated distribution of deglacial chronologies for the North American ice complex from glaciological modeling, Earth Planet. Sc. Lett., 315, 30–40, 2012.
Valcke, S.: The OASIS3 coupler: a European climate modelling community software, Geosci. Model Dev., 6, 373–388, https://doi.org/10.5194/gmd-6-373-2013, 2013.
Weber, S. L., Drijfhout, S. S., Abe-Ouchi, A., Crucifix, M., Eby, M., Ganopolski, A., Murakami, S., Otto-Bliesner, B., and Peltier, W. R.: The modern and glacial overturning circulation in the Atlantic ocean in PMIP coupled model simulations, Clim. Past, 3, 51–64, https://doi.org/10.5194/cp-3-51-2007, 2007.
Winguth, A., Archer, D., Duplessy, J.-C., Maier-Reimer, E., and Mikolajewicz, U.: Sensitivity of paleonutrient tracer distributions and deep-sea circulation to glacial boundary conditions, Paleoceanography, 14, 304–323, 1999.
Ziemen, F. A., Rodehacke, C. B., and Mikolajewicz, U.: Coupled ice sheet-climate modeling under glacial and pre-industrial boundary conditions, Clim. Past, 10, 1817–1836, https://doi.org/10.5194/cp-10-1817-2014, 2014.
Short summary
We study the response of the glacial AMOC to different forcings in a coupled AOGCM. The depth of the upper overturning cell remains almost unchanged in response to the full glacial forcing. This is the result of two opposing effects: a deepening due to the ice sheets and a shoaling due to the low GHG concentrations. Increased brine release in the Southern Ocean is key to the shoaling. With glacial ice sheets, a shallower cell can be simulated with GHG concentrations below the glacial level.
We study the response of the glacial AMOC to different forcings in a coupled AOGCM. The depth of...
