Articles | Volume 19, issue 5
https://doi.org/10.5194/cp-19-1101-2023
© Author(s) 2023. 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-19-1101-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Jun 2023
Research article |
| 01 Jun 2023
| 01 Jun 2023
Buoyancy forcing: a key driver of northern North Atlantic sea surface temperature variability across multiple timescales
Bjørg Risebrobakken
CORRESPONDING AUTHOR
NORCE Norwegian Research Center, Bjerknes Centre for Climate Research, Bergen, Norway
Mari F. Jensen
Department of Earth Sciences, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Helene R. Langehaug
Nansen Environmental and Remote Sensing Center, Bjerknes Centre for
Climate Research, Bergen, Norway
Tor Eldevik
Geophysical Institute, University of Bergen and Bjerknes Centre for
Climate Research, Bergen, Norway
Anne Britt Sandø
Institute of Marine Research, Bjerknes Centre for Climate Research,
Bergen, Norway
Camille Li
Geophysical Institute, University of Bergen and Bjerknes Centre for
Climate Research, Bergen, Norway
Andreas Born
Department of Earth Sciences, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Erin Louise McClymont
Department of Geography, Durham University, Durham, UK
Ulrich Salzmann
Department of Geography and Environmental Sciences, Northumbria
University, Newcastle upon Tyne, UK
Stijn De Schepper
NORCE Norwegian Research Center, Bjerknes Centre for Climate Research, Bergen, Norway
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Ingo Bethke, Yiguo Wang, François Counillon, Noel Keenlyside, Madlen Kimmritz, Filippa Fransner, Annette Samuelsen, Helene Langehaug, Lea Svendsen, Ping-Gin Chiu, Leilane Passos, Mats Bentsen, Chuncheng Guo, Alok Gupta, Jerry Tjiputra, Alf Kirkevåg, Dirk Olivié, Øyvind Seland, Julie Solsvik Vågane, Yuanchao Fan, and Tor Eldevik
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Andreas Born and Alexander Robinson
The Cryosphere, 15, 4539–4556, https://doi.org/10.5194/tc-15-4539-2021, https://doi.org/10.5194/tc-15-4539-2021, 2021
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Erica Madonna, David S. Battisti, Camille Li, and Rachel H. White
Weather Clim. Dynam., 2, 777–794, https://doi.org/10.5194/wcd-2-777-2021, https://doi.org/10.5194/wcd-2-777-2021, 2021
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Often in science we carry out experiments with computers in which several factors are explored, for example, in the field of climate science, how the factors of greenhouse gases, ice, and vegetation affect temperature. We can explore the relative importance of these factors by
swapping in and outdifferent values of these factors, and can also carry out experiments with many different combinations of these factors. This paper discusses how best to analyse the results from such experiments.
Tobias Zolles and Andreas Born
The Cryosphere, 15, 2917–2938, https://doi.org/10.5194/tc-15-2917-2021, https://doi.org/10.5194/tc-15-2917-2021, 2021
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We investigate the sensitivity of a glacier surface mass and the energy balance model of the Greenland ice sheet for the cold period of the Last Glacial Maximum (LGM) and the present-day climate. The results show that the model sensitivity changes with climate. While for present-day simulations inclusions of sublimation and hoar formation are of minor importance, they cannot be neglected during the LGM. To simulate the surface mass balance over long timescales, a water vapor scheme is necessary.
Charlotte L. Spencer-Jones, Erin L. McClymont, Nicole J. Bale, Ellen C. Hopmans, Stefan Schouten, Juliane Müller, E. Povl Abrahamsen, Claire Allen, Torsten Bickert, Claus-Dieter Hillenbrand, Elaine Mawbey, Victoria Peck, Aleksandra Svalova, and James A. Smith
Biogeosciences, 18, 3485–3504, https://doi.org/10.5194/bg-18-3485-2021, https://doi.org/10.5194/bg-18-3485-2021, 2021
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Long-term ocean temperature records are needed to fully understand the impact of West Antarctic Ice Sheet collapse. Glycerol dialkyl glycerol tetraethers (GDGTs) are powerful tools for reconstructing ocean temperature but can be difficult to apply to the Southern Ocean. Our results show active GDGT synthesis in relatively warm depths of the ocean. This research improves the application of GDGT palaeoceanographic proxies in the Southern Ocean.
Huiling Zou, Yongqi Gao, Helene R. Langehaug, Lei Yu, and Dong Guo
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-16, https://doi.org/10.5194/os-2021-16, 2021
Publication in OS not foreseen
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This work focuses on the the relationships between winter sea ice variability and thermodynamic processes in sea ice in the Bering Sea. It has been found that in the Norwegian Earth System Model, thermodynamics in sea ice plays an important role in winter sea ice variability and they can contribute over 70 % of winter sea ice mass incresea in the Bering Sea. The results can be very helpful to give a better understanding of sea ice changes in an Earth System Model.
David K. Hutchinson, Helen K. Coxall, Daniel J. Lunt, Margret Steinthorsdottir, Agatha M. de Boer, Michiel Baatsen, Anna von der Heydt, Matthew Huber, Alan T. Kennedy-Asser, Lutz Kunzmann, Jean-Baptiste Ladant, Caroline H. Lear, Karolin Moraweck, Paul N. Pearson, Emanuela Piga, Matthew J. Pound, Ulrich Salzmann, Howie D. Scher, Willem P. Sijp, Kasia K. Śliwińska, Paul A. Wilson, and Zhongshi Zhang
Clim. Past, 17, 269–315, https://doi.org/10.5194/cp-17-269-2021, https://doi.org/10.5194/cp-17-269-2021, 2021
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The Eocene–Oligocene transition was a major climate cooling event from a largely ice-free world to the first major glaciation of Antarctica, approximately 34 million years ago. This paper reviews observed changes in temperature, CO2 and ice sheets from marine and land-based records at this time. We present a new model–data comparison of this transition and find that CO2-forced cooling provides the best explanation of the observed global temperature changes.
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
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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.
Erin L. McClymont, Heather L. Ford, Sze Ling Ho, Julia C. Tindall, Alan M. Haywood, Montserrat Alonso-Garcia, Ian Bailey, Melissa A. Berke, Kate Littler, Molly O. Patterson, Benjamin Petrick, Francien Peterse, A. Christina Ravelo, Bjørg Risebrobakken, Stijn De Schepper, George E. A. Swann, Kaustubh Thirumalai, Jessica E. Tierney, Carolien van der Weijst, Sarah White, Ayako Abe-Ouchi, Michiel L. J. Baatsen, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Ran Feng, Chuncheng Guo, Anna S. von der Heydt, Stephen Hunter, Xiangyi Li, Gerrit Lohmann, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Christian Stepanek, and Zhongshi Zhang
Clim. Past, 16, 1599–1615, https://doi.org/10.5194/cp-16-1599-2020, https://doi.org/10.5194/cp-16-1599-2020, 2020
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We examine the sea-surface temperature response to an interval of climate ~ 3.2 million years ago, when CO2 concentrations were similar to today and the near future. Our geological data and climate models show that global mean sea-surface temperatures were 2.3 to 3.2 ºC warmer than pre-industrial climate, that the mid-latitudes and high latitudes warmed more than the tropics, and that the warming was particularly enhanced in the North Atlantic Ocean.
Peter Yu Feng Siew, Camille Li, Stefan Pieter Sobolowski, and Martin Peter King
Weather Clim. Dynam., 1, 261–275, https://doi.org/10.5194/wcd-1-261-2020, https://doi.org/10.5194/wcd-1-261-2020, 2020
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Arctic sea ice loss has been linked to changes in mid-latitude weather and climate. However, the literature offers differing views on the strength, robustness, and even existence of these linkages. We use a statistical tool (Causal Effect Networks) to show that one proposed pathway linking Barents–Kara ice and mid-latitude circulation is intermittent in observations and likely only active under certain conditions. This result may help explain apparent inconsistencies across previous studies.
Aurélie Marcelle Renée Aubry, Stijn De Schepper, and Anne de Vernal
J. Micropalaeontol., 39, 41–60, https://doi.org/10.5194/jm-39-41-2020, https://doi.org/10.5194/jm-39-41-2020, 2020
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We used organic-walled microfossils to better define the Plio–Pleistocene transition (2.56 Ma) that is associated with the intensification of the Northern Hemisphere glaciation. The disappearance of species around 2.75 Ma reflects an ecological response accompanying the Greenland ice sheet growth.
A strong regionalism marks the Labrador Sea and suggests cooler conditions than elsewhere in the North Atlantic, although our zone boundaries are contemporaneous with the eastern North Atlantic.
Maria Luisa Sánchez-Montes, Erin L. McClymont, Jeremy M. Lloyd, Juliane Müller, Ellen A. Cowan, and Coralie Zorzi
Clim. Past, 16, 299–313, https://doi.org/10.5194/cp-16-299-2020, https://doi.org/10.5194/cp-16-299-2020, 2020
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In this paper, we present new climate reconstructions in SW Alaska from recovered marine sediments in the Gulf of Alaska. We find that glaciers reached the Gulf of Alaska during a cooling climate 2.9 million years ago, and after that the Cordilleran Ice Sheet continued growing during a global drop in atmospheric CO2 levels. Cordilleran Ice Sheet growth could have been supported by an increase in heat supply to the SW Alaska and warm ocean evaporation–mountain precipitation mechanisms.
Tine Nilsen, Dmitry V. Divine, Annika Hofgaard, Andreas Born, Johann Jungclaus, and Igor Drobyshev
Clim. Past Discuss., https://doi.org/10.5194/cp-2019-123, https://doi.org/10.5194/cp-2019-123, 2019
Revised manuscript not accepted
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Using a set of three climate model simulations we cannot find a consistent relationship between atmospheric conditions favorable for forest fire activity in northern Scandinavia and weaker ocean circulation in the North Atlantic subpolar gyre on seasonal timescales. In the literature there is support of such a relationship for longer timescales. With the motivation to improve seasonal prediction systems, we conclude that the gyre circulation alone does not indicate forthcoming model drought.
Lise S. Graff, Trond Iversen, Ingo Bethke, Jens B. Debernard, Øyvind Seland, Mats Bentsen, Alf Kirkevåg, Camille Li, and Dirk J. L. Olivié
Earth Syst. Dynam., 10, 569–598, https://doi.org/10.5194/esd-10-569-2019, https://doi.org/10.5194/esd-10-569-2019, 2019
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Differences between a 1.5 and a 2.0 °C warmer global climate than 1850 conditions are discussed based on a suite of global atmosphere-only, fully coupled, and slab-ocean runs with the Norwegian Earth System Model. Responses, such as the Arctic amplification of global warming, are stronger with the fully coupled and slab-ocean configurations. While ice-free Arctic summers are rare under 1.5 °C warming in the slab-ocean runs, they are estimated to occur 18 % of the time under 2.0 °C warming.
Andreas Plach, Kerim H. Nisancioglu, Petra M. Langebroek, Andreas Born, and Sébastien Le clec'h
The Cryosphere, 13, 2133–2148, https://doi.org/10.5194/tc-13-2133-2019, https://doi.org/10.5194/tc-13-2133-2019, 2019
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Meltwater from the Greenland ice sheet (GrIS) rises sea level and knowing how the GrIS behaved in the past will help to become better in predicting its future. Here, the evolution of the past GrIS is shown to be dominated by how much ice melts (a result of the prevailing climate) rather than how ice flow is represented in the simulations. Therefore, it is very important to know past climates accurately, in order to be able to simulate the evolution of the GrIS and its contribution to sea level.
Christopher J. Hollis, Tom Dunkley Jones, Eleni Anagnostou, Peter K. Bijl, Marlow Julius Cramwinckel, Ying Cui, Gerald R. Dickens, Kirsty M. Edgar, Yvette Eley, David Evans, Gavin L. Foster, Joost Frieling, Gordon N. Inglis, Elizabeth M. Kennedy, Reinhard Kozdon, Vittoria Lauretano, Caroline H. Lear, Kate Littler, Lucas Lourens, A. Nele Meckler, B. David A. Naafs, Heiko Pälike, Richard D. Pancost, Paul N. Pearson, Ursula Röhl, Dana L. Royer, Ulrich Salzmann, Brian A. Schubert, Hannu Seebeck, Appy Sluijs, Robert P. Speijer, Peter Stassen, Jessica Tierney, Aradhna Tripati, Bridget Wade, Thomas Westerhold, Caitlyn Witkowski, James C. Zachos, Yi Ge Zhang, Matthew Huber, and Daniel J. Lunt
Geosci. Model Dev., 12, 3149–3206, https://doi.org/10.5194/gmd-12-3149-2019, https://doi.org/10.5194/gmd-12-3149-2019, 2019
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The Deep-Time Model Intercomparison Project (DeepMIP) is a model–data intercomparison of the early Eocene (around 55 million years ago), the last time that Earth's atmospheric CO2 concentrations exceeded 1000 ppm. Previously, we outlined the experimental design for climate model simulations. Here, we outline the methods used for compilation and analysis of climate proxy data. The resulting climate
atlaswill provide insights into the mechanisms that control past warm climate states.
Andreas Born, Michael A. Imhof, and Thomas F. Stocker
The Cryosphere, 13, 1529–1546, https://doi.org/10.5194/tc-13-1529-2019, https://doi.org/10.5194/tc-13-1529-2019, 2019
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We present a new numerical model to simulate the surface energy and mass balance of snow and ice. While similar models exist and cover a wide range of complexity from empirical models to those that simulate the microscopic structure of individual snow grains, we aim to strike a balance between physical completeness and numerical efficiency. This new model will enable physically accurate simulations over timescales of hundreds of millennia, a key requirement of investigating ice age cycles.
Florence Sylvestre, Mathieu Schuster, Hendrik Vogel, Moussa Abdheramane, Daniel Ariztegui, Ulrich Salzmann, Antje Schwalb, Nicolas Waldmann, and the ICDP CHADRILL Consortium
Sci. Dril., 24, 71–78, https://doi.org/10.5194/sd-24-71-2018, https://doi.org/10.5194/sd-24-71-2018, 2018
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CHADRILL aims to recover a sedimentary core spanning the Miocene–Pleistocene sediment succession of Lake Chad through deep drilling. This record will provide significant insights into the modulation of orbitally forced changes in northern African hydroclimate under different climate boundary conditions and the most continuous climatic and environmental record to be compared with hominid migrations across northern Africa and the implications for understanding human evolution.
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.
Anna Binczewska, Bjørg Risebrobakken, Irina Polovodova Asteman, Matthias Moros, Amandine Tisserand, Eystein Jansen, and Andrzej Witkowski
Biogeosciences, 15, 5909–5928, https://doi.org/10.5194/bg-15-5909-2018, https://doi.org/10.5194/bg-15-5909-2018, 2018
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Primary productivity is an important factor in the functioning and structuring of the coastal ecosystem. Thus, two sediment cores from the Skagerrak (North Sea) were investigated in order to obtain a comprehensive picture of primary productivity changes during the last millennium and identify associated forcing factors (e.g. anthropogenic, climate). The cores were dated and analysed for palaeoproductivity proxies and palaeothermometers.
Ariadna Salabarnada, Carlota Escutia, Ursula Röhl, C. Hans Nelson, Robert McKay, Francisco J. Jiménez-Espejo, Peter K. Bijl, Julian D. Hartman, Stephanie L. Strother, Ulrich Salzmann, Dimitris Evangelinos, Adrián López-Quirós, José Abel Flores, Francesca Sangiorgi, Minoru Ikehara, and Henk Brinkhuis
Clim. Past, 14, 991–1014, https://doi.org/10.5194/cp-14-991-2018, https://doi.org/10.5194/cp-14-991-2018, 2018
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Here we reconstruct ice sheet and paleoceanographic configurations in the East Antarctic Wilkes Land margin based on a multi-proxy study conducted in late Oligocene (26–25 Ma) sediments from IODP Site U1356. The new obliquity-forced glacial–interglacial sedimentary model shows that, under the high CO2 values of the late Oligocene, ice sheets had mostly retreated to their terrestrial margins and the ocean was very dynamic with shifting positions of the polar fronts and associated water masses.
Zhongshi Zhang, Qing Yan, Elizabeth J. Farmer, Camille Li, Gilles Ramstein, Terence Hughes, Martin Jakobsson, Matt O'Regan, Ran Zhang, Ning Tan, Camille Contoux, Christophe Dumas, and Chuncheng Guo
Clim. Past Discuss., https://doi.org/10.5194/cp-2018-79, https://doi.org/10.5194/cp-2018-79, 2018
Revised manuscript not accepted
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Our study challenges the widely accepted idea that the Laurentide-Eurasian ice sheets gradually extended across North America and Northwest Eurasia, and suggests the growth of the NH ice sheets is much more complicated. We find climate feedbacks regulate the distribution of the NH ice sheets, producing swings between two distinct ice sheet configurations: the Laurentide-Eurasian and a circum-Arctic configuration, where large ice sheets existed over Northeast Siberia and the Canadian Rockies.
Mari F. Jensen, Aleksi Nummelin, Søren B. Nielsen, Henrik Sadatzki, Evangeline Sessford, Bjørg Risebrobakken, Carin Andersson, Antje Voelker, William H. G. Roberts, Joel Pedro, and Andreas Born
Clim. Past, 14, 901–922, https://doi.org/10.5194/cp-14-901-2018, https://doi.org/10.5194/cp-14-901-2018, 2018
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We combine North Atlantic sea-surface temperature reconstructions and global climate model simulations to study rapid glacial climate shifts (30–40 000 years ago). Pre-industrial climate boosts similar, albeit weaker, sea-surface temperature variability as the glacial period. However, in order to reproduce most of the amplitude of this variability, and to see temperature variability in Greenland similar to the ice-core record, although with a smaller amplitude, we need forced simulations.
Camille Li, Clio Michel, Lise Seland Graff, Ingo Bethke, Giuseppe Zappa, Thomas J. Bracegirdle, Erich Fischer, Ben J. Harvey, Trond Iversen, Martin P. King, Harinarayan Krishnan, Ludwig Lierhammer, Daniel Mitchell, John Scinocca, Hideo Shiogama, Dáithí A. Stone, and Justin J. Wettstein
Earth Syst. Dynam., 9, 359–382, https://doi.org/10.5194/esd-9-359-2018, https://doi.org/10.5194/esd-9-359-2018, 2018
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This study investigates the midlatitude atmospheric circulation response to 1.5°C and 2.0°C of warming using modelling experiments run for the HAPPI project (Half a degree Additional warming, Prognosis & Projected Impacts). While the chaotic nature of the atmospheric flow dominates in these low-end warming scenarios, some local changes emerge. Case studies explore precipitation impacts both for regions that dry (Mediterranean) and regions that get wetter (Europe, North American west coast).
Paul E. Bachem, Bjørg Risebrobakken, Stijn De Schepper, and Erin L. McClymont
Clim. Past, 13, 1153–1168, https://doi.org/10.5194/cp-13-1153-2017, https://doi.org/10.5194/cp-13-1153-2017, 2017
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We present a high-resolution multi-proxy study of the Norwegian Sea, covering the 5.33 to 3.14 Ma time window within the Pliocene. We show that large-scale climate transitions took place during this warmer than modern time, most likely in response to ocean gateway transformations. Strong warming at 4.0 Ma in the Norwegian Sea, when regions closer to Greenland cooled, indicate that increased northward ocean heat transport may be compatible with expanding glaciation and Arctic sea ice growth.
Jack Longman, Daniel Veres, Vasile Ersek, Ulrich Salzmann, Katalin Hubay, Marc Bormann, Volker Wennrich, and Frank Schäbitz
Clim. Past, 13, 897–917, https://doi.org/10.5194/cp-13-897-2017, https://doi.org/10.5194/cp-13-897-2017, 2017
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We present the first record of dust input into an eastern European bog over the past 10 800 years. We find significant changes in past dust deposition, with large inputs related to both natural and human influences. We show evidence that Saharan desertification has had a significant impact on dust deposition in eastern Europe for the past 6100 years.
Stephanie L. Strother, Ulrich Salzmann, Francesca Sangiorgi, Peter K. Bijl, Jörg Pross, Carlota Escutia, Ariadna Salabarnada, Matthew J. Pound, Jochen Voss, and John Woodward
Biogeosciences, 14, 2089–2100, https://doi.org/10.5194/bg-14-2089-2017, https://doi.org/10.5194/bg-14-2089-2017, 2017
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One of the main challenges in Antarctic vegetation reconstructions is the uncertainty in unambiguously identifying reworked pollen and spore assemblages in marine sedimentary records influenced by waxing and waning ice sheets. This study uses red fluorescence and digital imaging as a new tool to identify reworking in a marine sediment core from circum-Antarctic waters to reconstruct Cenozoic climate change and vegetation with high confidence.
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.
Harry Dowsett, Aisling Dolan, David Rowley, Robert Moucha, Alessandro M. Forte, Jerry X. Mitrovica, Matthew Pound, Ulrich Salzmann, Marci Robinson, Mark Chandler, Kevin Foley, and Alan Haywood
Clim. Past, 12, 1519–1538, https://doi.org/10.5194/cp-12-1519-2016, https://doi.org/10.5194/cp-12-1519-2016, 2016
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Past intervals in Earth history provide unique windows into conditions much different than those observed today. We investigated the paleoenvironments of a past warm interval (~ 3 million years ago). Our reconstruction includes data sets for surface temperature, vegetation, soils, lakes, ice sheets, topography, and bathymetry. These data are being used along with global climate models to expand our understanding of the climate system and to help us prepare for future changes.
Sina Panitz, Ulrich Salzmann, Bjørg Risebrobakken, Stijn De Schepper, and Matthew J. Pound
Clim. Past, 12, 1043–1060, https://doi.org/10.5194/cp-12-1043-2016, https://doi.org/10.5194/cp-12-1043-2016, 2016
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This paper presents the first late Pliocene high-resolution pollen record for the Norwegian Arctic, covering the time period 3.60 to 3.14 million years ago (Ma). The climate of the late Pliocene has been widely regarded as relatively stable. Our results suggest a high climate variability with alternating cool temperate forests during warmer-than-presen periods and boreal forests similar to today during cooler intervals. A spread of peatlands at the expense of forest indicates long-term cooling.
Alan M. Haywood, Harry J. Dowsett, Aisling M. Dolan, David Rowley, Ayako Abe-Ouchi, Bette Otto-Bliesner, Mark A. Chandler, Stephen J. Hunter, Daniel J. Lunt, Matthew Pound, and Ulrich Salzmann
Clim. Past, 12, 663–675, https://doi.org/10.5194/cp-12-663-2016, https://doi.org/10.5194/cp-12-663-2016, 2016
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Our paper presents the experimental design for the second phase of the Pliocene Model Intercomparison Project (PlioMIP). We outline the way in which climate models should be set up in order to study the Pliocene – a period of global warmth in Earth's history which is relevant for our understanding of future climate change. By conducting a model intercomparison we hope to understand the uncertainty associated with model predictions of a warmer climate.
K. Lohmann, J. Mignot, H. R. Langehaug, J. H. Jungclaus, D. Matei, O. H. Otterå, Y. Q. Gao, T. L. Mjell, U. S. Ninnemann, and H. F. Kleiven
Clim. Past, 11, 203–216, https://doi.org/10.5194/cp-11-203-2015, https://doi.org/10.5194/cp-11-203-2015, 2015
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We use model simulations to investigate mechanisms of similar Iceland--Scotland overflow (outflow from the Nordic seas) and North Atlantic sea surface temperature variability, suggested from palaeo-reconstructions (Mjell et al., 2015). Our results indicate the influence of Nordic Seas surface temperature on the pressure gradient across the Iceland--Scotland ridge, not a large-scale link through the meridional overturning circulation, is responsible for the (simulated) co-variability.
M. J. Pound, J. Tindall, S. J. Pickering, A. M. Haywood, H. J. Dowsett, and U. Salzmann
Clim. Past, 10, 167–180, https://doi.org/10.5194/cp-10-167-2014, https://doi.org/10.5194/cp-10-167-2014, 2014
R. J. Telford, C. Li, and M. Kucera
Clim. Past, 9, 859–870, https://doi.org/10.5194/cp-9-859-2013, https://doi.org/10.5194/cp-9-859-2013, 2013
Related subject area
Subject: Ocean Dynamics | Archive: Marine Archives | Timescale: Cenozoic
Impact of the Late Miocene Cooling on the loss of coral reefs in the Central Indo-Pacific
Nonlinear increase in seawater 87Sr ∕ 86Sr in the Oligocene to early Miocene and implications for climate-sensitive weathering
Limited exchange between the deep Pacific and Atlantic oceans during the warm mid-Pliocene and Marine Isotope Stage M2 “glaciation”
Late Cenozoic sea-surface-temperature evolution of the South Atlantic Ocean
Lipid-biomarker-based sea surface temperature record offshore Tasmania over the last 23 million years
Late Neogene nannofossil assemblages as tracers of ocean circulation and paleoproductivity over the NW Australian shelf
Plio-Pleistocene Perth Basin water temperatures and Leeuwin Current dynamics (Indian Ocean) derived from oxygen and clumped-isotope paleothermometry
Temperate Oligocene surface ocean conditions offshore of Cape Adare, Ross Sea, Antarctica
A revised mid-Pliocene composite section centered on the M2 glacial event for ODP Site 846
Lessons from a high-CO2 world: an ocean view from ∼ 3 million years ago
Late Pliocene Cordilleran Ice Sheet development with warm northeast Pacific sea surface temperatures
Understanding the mechanisms behind high glacial productivity in the southern Brazilian margin
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 3: Insights from Oligocene–Miocene TEX86-based sea surface temperature reconstructions
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 2: Insights from Oligocene–Miocene dinoflagellate cyst assemblages
Variations in Mediterranean–Atlantic exchange across the late Pliocene climate transition
Revisiting the Ceara Rise, equatorial Atlantic Ocean: isotope stratigraphy of ODP Leg 154 from 0 to 5 Ma
Constraints on ocean circulation at the Paleocene–Eocene Thermal Maximum from neodymium isotopes
Expansion and diversification of high-latitude radiolarian assemblages in the late Eocene linked to a cooling event in the southwest Pacific
Microfossil evidence for trophic changes during the Eocene–Oligocene transition in the South Atlantic (ODP Site 1263, Walvis Ridge)
A major change in North Atlantic deep water circulation 1.6 million years ago
Contribution of changes in opal productivity and nutrient distribution in the coastal upwelling systems to Late Pliocene/Early Pleistocene climate cooling
Productivity response of calcareous nannoplankton to Eocene Thermal Maximum 2 (ETM2)
Technical note: Late Pliocene age control and composite depths at ODP Site 982, revisited
Pliocene three-dimensional global ocean temperature reconstruction
Benjamin Fredericks Petrick, Lars Reuning, Miriam Pfeiffer, Gerald Auer, and Lorenz Schwark
Clim. Past Discuss., https://doi.org/10.5194/cp-2024-28, https://doi.org/10.5194/cp-2024-28, 2024
Revised manuscript accepted for CP
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It is known that there was a lack of coral reefs in the Central Indo-Pacific during the Pliocene. The cause of this is unknown. This study uses a new SST record biased on biomarkers from the Coral Sea between 11–2 Ma to demonstrate a 2-degree cooling in the Central Indo-Pacific as part of the Late Miocene Cooling. When combined with other impacts associated with this event, this might explain the collapse of coral reefs. The new data shows the importance of SST changes in Coral Reef loss.
Heather M. Stoll, Leopoldo D. Pena, Ivan Hernandez-Almeida, José Guitián, Thomas Tanner, and Heiko Pälike
Clim. Past, 20, 25–36, https://doi.org/10.5194/cp-20-25-2024, https://doi.org/10.5194/cp-20-25-2024, 2024
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The Oligocene and early Miocene periods featured dynamic glacial cycles on Antarctica. In this paper, we use Sr isotopes in marine carbonate sediments to document a change in the location and intensity of continental weathering during short periods of very intense Antarctic glaciation. Potentially, the weathering intensity of old continental rocks on Antarctica was reduced during glaciation. We also show improved age models for correlation of Southern Ocean and North Atlantic sediments.
Anna Hauge Braaten, Kim A. Jakob, Sze Ling Ho, Oliver Friedrich, Eirik Vinje Galaasen, Stijn De Schepper, Paul A. Wilson, and Anna Nele Meckler
Clim. Past, 19, 2109–2125, https://doi.org/10.5194/cp-19-2109-2023, https://doi.org/10.5194/cp-19-2109-2023, 2023
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In the context of understanding current global warming, the middle Pliocene (3.3–3.0 million years ago) is an important interval in Earth's history because atmospheric carbon dioxide concentrations were similar to levels today. We have reconstructed deep-sea temperatures at two different locations for this period, and find that a very different mode of ocean circulation or mixing existed, with important implications for how heat was transported in the deep ocean.
Frida S. Hoem, Adrián López-Quirós, Suzanna van de Lagemaat, Johan Etourneau, Marie-Alexandrine Sicre, Carlota Escutia, Henk Brinkhuis, Francien Peterse, Francesca Sangiorgi, and Peter K. Bijl
Clim. Past, 19, 1931–1949, https://doi.org/10.5194/cp-19-1931-2023, https://doi.org/10.5194/cp-19-1931-2023, 2023
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We present two new sea surface temperature (SST) records in comparison with available SST records to reconstruct South Atlantic paleoceanographic evolution. Our results show a low SST gradient in the Eocene–early Oligocene due to the persistent gyral circulation. A higher SST gradient in the Middle–Late Miocene infers a stronger circumpolar current. The southern South Atlantic was the coldest region in the Southern Ocean and likely the main deep-water formation location in the Middle Miocene.
Suning Hou, Foteini Lamprou, Frida S. Hoem, Mohammad Rizky Nanda Hadju, Francesca Sangiorgi, Francien Peterse, and Peter K. Bijl
Clim. Past, 19, 787–802, https://doi.org/10.5194/cp-19-787-2023, https://doi.org/10.5194/cp-19-787-2023, 2023
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Neogene climate cooling is thought to be accompanied by increased Equator-to-pole temperature gradients, but mid-latitudes are poorly represented. We use biomarkers to reconstruct a 23 Myr continuous sea surface temperature record of the mid-latitude Southern Ocean. We note a profound mid-latitude cooling which narrowed the latitudinal temperature gradient with the northward expansion of subpolar conditions. We surmise that this reflects the strengthening of the ACC and the expansion of sea ice.
Boris-Theofanis Karatsolis and Jorijntje Henderiks
Clim. Past, 19, 765–786, https://doi.org/10.5194/cp-19-765-2023, https://doi.org/10.5194/cp-19-765-2023, 2023
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Ocean circulation around NW Australia plays a key role in regulating the climate in the area and is characterised by seasonal variations in the activity of a major boundary current named the Leeuwin Current. By investigating nannofossils found in sediment cores recovered from the NW Australian shelf, we reconstructed ocean circulation in the warmer-than-present world from 6 to 3.5 Ma, as mirrored by long-term changes in stratification and nutrient availability.
David De Vleeschouwer, Marion Peral, Marta Marchegiano, Angelina Füllberg, Niklas Meinicke, Heiko Pälike, Gerald Auer, Benjamin Petrick, Christophe Snoeck, Steven Goderis, and Philippe Claeys
Clim. Past, 18, 1231–1253, https://doi.org/10.5194/cp-18-1231-2022, https://doi.org/10.5194/cp-18-1231-2022, 2022
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The Leeuwin Current transports warm water along the western coast of Australia: from the tropics to the Southern Hemisphere midlatitudes. Therewith, the current influences climate in two ways: first, as a moisture source for precipitation in southwestern Australia; second, as a vehicle for Equator-to-pole heat transport. In this study, we study sediment cores along the Leeuwin Current pathway to understand its ocean–climate interactions between 4 and 2 Ma.
Frida S. Hoem, Luis Valero, Dimitris Evangelinos, Carlota Escutia, Bella Duncan, Robert M. McKay, Henk Brinkhuis, Francesca Sangiorgi, and Peter K. Bijl
Clim. Past, 17, 1423–1442, https://doi.org/10.5194/cp-17-1423-2021, https://doi.org/10.5194/cp-17-1423-2021, 2021
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We present new offshore palaeoceanographic reconstructions for the Oligocene (33.7–24.4 Ma) in the Ross Sea, Antarctica. Our study of dinoflagellate cysts and lipid biomarkers indicates warm-temperate sea surface conditions. We posit that warm surface-ocean conditions near the continental shelf during the Oligocene promoted increased precipitation and heat delivery towards Antarctica that led to dynamic terrestrial ice sheet volumes in the warmer climate state of the Oligocene.
Timothy D. Herbert, Rocio Caballero-Gill, and Joseph B. Novak
Clim. Past, 17, 1385–1394, https://doi.org/10.5194/cp-17-1385-2021, https://doi.org/10.5194/cp-17-1385-2021, 2021
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The Pliocene represents a geologically warm period with polar ice restricted to the Antarctic. Nevertheless, variability and ice volume persisted in the Pliocene. This work revisits a classic site on which much of our understanding of Pliocene paleoclimate variability is based and corrects errors in data sets related to ice volume and ocean surface temperature. In particular, it generates an improved representation of an enigmatic glacial episode in Pliocene times (circa 3.3 Ma).
Erin L. McClymont, Heather L. Ford, Sze Ling Ho, Julia C. Tindall, Alan M. Haywood, Montserrat Alonso-Garcia, Ian Bailey, Melissa A. Berke, Kate Littler, Molly O. Patterson, Benjamin Petrick, Francien Peterse, A. Christina Ravelo, Bjørg Risebrobakken, Stijn De Schepper, George E. A. Swann, Kaustubh Thirumalai, Jessica E. Tierney, Carolien van der Weijst, Sarah White, Ayako Abe-Ouchi, Michiel L. J. Baatsen, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Ran Feng, Chuncheng Guo, Anna S. von der Heydt, Stephen Hunter, Xiangyi Li, Gerrit Lohmann, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Christian Stepanek, and Zhongshi Zhang
Clim. Past, 16, 1599–1615, https://doi.org/10.5194/cp-16-1599-2020, https://doi.org/10.5194/cp-16-1599-2020, 2020
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We examine the sea-surface temperature response to an interval of climate ~ 3.2 million years ago, when CO2 concentrations were similar to today and the near future. Our geological data and climate models show that global mean sea-surface temperatures were 2.3 to 3.2 ºC warmer than pre-industrial climate, that the mid-latitudes and high latitudes warmed more than the tropics, and that the warming was particularly enhanced in the North Atlantic Ocean.
Maria Luisa Sánchez-Montes, Erin L. McClymont, Jeremy M. Lloyd, Juliane Müller, Ellen A. Cowan, and Coralie Zorzi
Clim. Past, 16, 299–313, https://doi.org/10.5194/cp-16-299-2020, https://doi.org/10.5194/cp-16-299-2020, 2020
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In this paper, we present new climate reconstructions in SW Alaska from recovered marine sediments in the Gulf of Alaska. We find that glaciers reached the Gulf of Alaska during a cooling climate 2.9 million years ago, and after that the Cordilleran Ice Sheet continued growing during a global drop in atmospheric CO2 levels. Cordilleran Ice Sheet growth could have been supported by an increase in heat supply to the SW Alaska and warm ocean evaporation–mountain precipitation mechanisms.
Rodrigo da Costa Portilho-Ramos, Tainã Marcos Lima Pinho, Cristiano Mazur Chiessi, and Cátia Fernandes Barbosa
Clim. Past, 15, 943–955, https://doi.org/10.5194/cp-15-943-2019, https://doi.org/10.5194/cp-15-943-2019, 2019
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Fossil microorganisms from the last glacial found in marine sediments collected off southern Brazil suggest that more productive austral summer upwelling and more frequent austral winter incursions of nutrient-rich waters from the Plata River boosted regional productivity year-round. While upwelling was more productive due to the higher silicon content from the Southern Ocean, more frequent riverine incursions were modulated by stronger alongshore southwesterly winds.
Julian D. Hartman, Francesca Sangiorgi, Ariadna Salabarnada, Francien Peterse, Alexander J. P. Houben, Stefan Schouten, Henk Brinkhuis, Carlota Escutia, and Peter K. Bijl
Clim. Past, 14, 1275–1297, https://doi.org/10.5194/cp-14-1275-2018, https://doi.org/10.5194/cp-14-1275-2018, 2018
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We reconstructed sea surface temperatures for the Oligocene and Miocene periods (34–11 Ma) based on archaeal lipids from a site close to the Wilkes Land coast, Antarctica. Our record suggests generally warm to temperate surface waters: on average 17 °C. Based on the lithology, glacial and interglacial temperatures could be distinguished, showing an average 3 °C offset. The long-term temperature trend resembles the benthic δ18O stack, which may have implications for ice volume reconstructions.
Peter K. Bijl, Alexander J. P. Houben, Julian D. Hartman, Jörg Pross, Ariadna Salabarnada, Carlota Escutia, and Francesca Sangiorgi
Clim. Past, 14, 1015–1033, https://doi.org/10.5194/cp-14-1015-2018, https://doi.org/10.5194/cp-14-1015-2018, 2018
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We document Southern Ocean surface ocean conditions and changes therein during the Oligocene and Miocene (34–10 Myr ago). We infer profound long-term and short-term changes in ice-proximal oceanographic conditions: sea surface temperature, nutrient conditions and sea ice. Our results point to warm-temperate, oligotrophic, ice-proximal oceanographic conditions. These distinct oceanographic conditions may explain the high amplitude in inferred Oligocene–Miocene Antarctic ice volume changes.
Ángela García-Gallardo, Patrick Grunert, and Werner E. Piller
Clim. Past, 14, 339–350, https://doi.org/10.5194/cp-14-339-2018, https://doi.org/10.5194/cp-14-339-2018, 2018
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We study the variability in Mediterranean–Atlantic exchange, focusing on the surface Atlantic inflow across the mid-Pliocene warm period and the onset of the Northern Hemisphere glaciation, still unresolved by previous works. Oxygen isotope gradients between both sides of the Strait of Gibraltar reveal weak inflow during warm periods that turns stronger during severe glacials and the start of a negative feedback between exchange at the Strait and the Atlantic Meridional Overturning Circulation.
Roy H. Wilkens, Thomas Westerhold, Anna J. Drury, Mitchell Lyle, Thomas Gorgas, and Jun Tian
Clim. Past, 13, 779–793, https://doi.org/10.5194/cp-13-779-2017, https://doi.org/10.5194/cp-13-779-2017, 2017
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Here we introduce the Code for Ocean Drilling Data (CODD), a unified and consistent system for integrating disparate data streams such as micropaleontology, physical properties, core images, geochemistry, and borehole logging. As a test case, data from Ocean Drilling Program Leg 154 (Ceara Rise – western equatorial Atlantic) were assembled into a new regional composite benthic stable isotope record covering the last 5 million years.
April N. Abbott, Brian A. Haley, Aradhna K. Tripati, and Martin Frank
Clim. Past, 12, 837–847, https://doi.org/10.5194/cp-12-837-2016, https://doi.org/10.5194/cp-12-837-2016, 2016
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The Paleocene-Eocene Thermal Maximum (PETM) was a brief period when the Earth was in an extreme greenhouse state. We use neodymium isotopes to suggest that during this time deep-ocean circulation was distinct in each basin (North and South Atlanic, Southern, Pacific) with little exchange between. Moreover, the Pacific data show the most variability, suggesting this was a critical region possibly involved in both PETM triggering and remediation.
K. M. Pascher, C. J. Hollis, S. M. Bohaty, G. Cortese, R. M. McKay, H. Seebeck, N. Suzuki, and K. Chiba
Clim. Past, 11, 1599–1620, https://doi.org/10.5194/cp-11-1599-2015, https://doi.org/10.5194/cp-11-1599-2015, 2015
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Radiolarian taxa with high-latitude affinities are present from at least the middle Eocene in the SW Pacific and become very abundant in the late Eocene at all investigated sites. A short incursion of low-latitude taxa is observed during the MECO and late Eocene warming event at Site 277. Radiolarian abundance, diversity and taxa with high-latitude affinities increase at Site 277 in two steps in the latest Eocene due to climatic cooling and expansion of cold water masses.
M. Bordiga, J. Henderiks, F. Tori, S. Monechi, R. Fenero, A. Legarda-Lisarri, and E. Thomas
Clim. Past, 11, 1249–1270, https://doi.org/10.5194/cp-11-1249-2015, https://doi.org/10.5194/cp-11-1249-2015, 2015
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Deep-sea sediments at ODP Site 1263 (Walvis Ridge, South Atlantic) show that marine calcifying algae decreased in abundance and size at the Eocene-Oligocene boundary, when the Earth transitioned from a greenhouse to a more glaciated and cooler climate. This decreased the food supply for benthic foraminifer communities. The plankton rapidly responded to fast-changing conditions, such as seasonal nutrient availability, or to threshold-levels in pCO2, cooling and ocean circulation.
N. Khélifi and M. Frank
Clim. Past, 10, 1441–1451, https://doi.org/10.5194/cp-10-1441-2014, https://doi.org/10.5194/cp-10-1441-2014, 2014
J. Etourneau, C. Ehlert, M. Frank, P. Martinez, and R. Schneider
Clim. Past, 8, 1435–1445, https://doi.org/10.5194/cp-8-1435-2012, https://doi.org/10.5194/cp-8-1435-2012, 2012
M. Dedert, H. M. Stoll, D. Kroon, N. Shimizu, K. Kanamaru, and P. Ziveri
Clim. Past, 8, 977–993, https://doi.org/10.5194/cp-8-977-2012, https://doi.org/10.5194/cp-8-977-2012, 2012
N. Khélifi, M. Sarnthein, and B. D. A. Naafs
Clim. Past, 8, 79–87, https://doi.org/10.5194/cp-8-79-2012, https://doi.org/10.5194/cp-8-79-2012, 2012
H. J. Dowsett, M. M. Robinson, and K. M. Foley
Clim. Past, 5, 769–783, https://doi.org/10.5194/cp-5-769-2009, https://doi.org/10.5194/cp-5-769-2009, 2009
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Short summary
In the observational period, spatially coherent sea surface temperatures characterize the northern North Atlantic at multidecadal timescales. We show that spatially non-coherent temperature patterns are seen both in further projections and a past warm climate period with a CO2 level comparable to the future low-emission scenario. Buoyancy forcing is shown to be important for northern North Atlantic temperature patterns.
In the observational period, spatially coherent sea surface temperatures characterize the...
