Articles | Volume 20, issue 6
https://doi.org/10.5194/cp-20-1303-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-20-1303-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Polar amplification of orbital-scale climate variability in the early Eocene greenhouse world
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Tobias Agterhuis
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
now at: School of Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, SO14 3ZH, United Kingdom
Danielle Gerritsma
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Myrthe de Goeij
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Xiaoqing Liu
Earth, Atmospheric, and Planetary Sciences Department, Purdue University, West Lafayette, IN 47907-2051, USA
Pauline de Regt
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Addison Rice
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Laurens Vennema
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Claudia Agnini
Dipartimento di Geoscienze, Universita degli Studi di Padua, 35131 Padua, Italy
Peter K. Bijl
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Joost Frieling
Department of Earth Sciences, University of Oxford, Oxford, OX1 3AN, United Kingdom
Matthew Huber
Earth, Atmospheric, and Planetary Sciences Department, Purdue University, West Lafayette, IN 47907-2051, USA
Francien Peterse
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
Appy Sluijs
Department of Earth Sciences, Faculty of Geosciences, Utrecht University, 3584CB Utrecht, the Netherlands
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Suning Hou, Leonie Toebrock, Mart van der Linden, Fleur Rothstegge, Martin Ziegler, Lucas J. Lourens, and Peter K. Bijl
Clim. Past, 21, 79–93, https://doi.org/10.5194/cp-21-79-2025, https://doi.org/10.5194/cp-21-79-2025, 2025
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Based on dinoflagellate cyst assemblages and sea surface temperature records west of offshore Tasmania, we find a northward migration and freshening of the subtropical front, not at the M2 glacial maximum but at its deglaciation phase. This oceanographic change aligns well with trends in pCO2. We propose that iceberg discharge from the M2 deglaciation freshened the subtropical front, which together with the other oceanographic changes affected atmosphere–ocean CO2 exchange in the Southern Ocean.
Frida S. Hoem, Karlijn van den Broek, Adrián López-Quirós, Suzanna H. A. van de Lagemaat, Steve M. Bohaty, Claus-Dieter Hillenbrand, Robert D. Larter, Tim E. van Peer, Henk Brinkhuis, Francesca Sangiorgi, and Peter K. Bijl
J. Micropalaeontol., 43, 497–517, https://doi.org/10.5194/jm-43-497-2024, https://doi.org/10.5194/jm-43-497-2024, 2024
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The timing and impact of onset of Antarctic Circumpolar Current (ACC) on climate and Antarctic ice are unclear. We reconstruct late Eocene to Miocene southern Atlantic surface ocean environment using microfossil remains of dinoflagellates (dinocysts). Our dinocyst records shows the breakdown of subpolar gyres in the late Oligocene and the transition into a modern-like oceanographic regime with ACC flow, established frontal systems, Antarctic proximal cooling, and sea ice by the late Miocene.
Appy Sluijs and Henk Brinkhuis
J. Micropalaeontol., 43, 441–474, https://doi.org/10.5194/jm-43-441-2024, https://doi.org/10.5194/jm-43-441-2024, 2024
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We present intrinsic details of dinocyst taxa and assemblages from the sole available central Arctic late Paleocene–early Eocene sedimentary succession recovered at the central Lomonosov Ridge by the Integrated Ocean Drilling Program (IODP) Expedition 302. We develop a pragmatic taxonomic framework, document critical biostratigraphic events, and propose two new genera and seven new species.
Dominique K. L. L. Jenny, Tammo Reichgelt, Charlotte L. O'Brien, Xiaoqing Liu, Peter K. Bijl, Matthew Huber, and Appy Sluijs
Clim. Past, 20, 1627–1657, https://doi.org/10.5194/cp-20-1627-2024, https://doi.org/10.5194/cp-20-1627-2024, 2024
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This study reviews the current state of knowledge regarding the Oligocene
icehouseclimate. We extend an existing marine climate proxy data compilation and present a new compilation and analysis of terrestrial plant assemblages to assess long-term climate trends and variability. Our data–climate model comparison reinforces the notion that models underestimate polar amplification of Oligocene climates, and we identify potential future research directions.
Mark Vinz Elbertsen, Erik van Sebille, and Peter Kristian Bijl
EGUsphere, https://doi.org/10.5194/egusphere-2024-1596, https://doi.org/10.5194/egusphere-2024-1596, 2024
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This work verifies the remarkable finds of late Eocene Antarctic-sourced iceberg-rafted debris found on South Orkney. We find that these icebergs must have been on the larger end of the size scale compared to today’s icebergs due to faster melting in the warmer Eocene climate. The study was performed using a high-resolution model in which individual icebergs were followed through time.
Alice Paine, Joost Frieling, Timothy Shanahan, Tamsin Mather, Nicholas McKay, Stuart Robinson, David Pyle, Isabel Fendley, Ruth Kiely, and William Gosling
EGUsphere, https://doi.org/10.5194/egusphere-2024-2123, https://doi.org/10.5194/egusphere-2024-2123, 2024
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Few tropical Hg records extend beyond ~12 ka, meaning our current understanding of Hg behaviour may not fully account for the impact of long-term hydroclimate changes on the Hg cycle in these environments. Here, we present a ~96,000-year Hg record from Lake Bosumtwi, Ghana. A coupled response is observed between Hg flux and shifts in sediment composition reflective of changes in lake level, and suggesting that hydroclimate may be a key driver of tropical Hg cycling over millennial-timescales.
Allix J. Baxter, Francien Peterse, Dirk Verschuren, Aihemaiti Maitituerdi, Nicolas Waldmann, and Jaap S. Sinninghe Damsté
Biogeosciences, 21, 2877–2908, https://doi.org/10.5194/bg-21-2877-2024, https://doi.org/10.5194/bg-21-2877-2024, 2024
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This study investigates the impact of long-term lake-system evolution on the climate signal recorded by glycerol dialkyl glycerol tetraethers (GDGTs), a popular biomarker in paleoclimate research. It compares downcore changes in GDGTs in the 250 000 year sediment sequence of Lake Chala (Kenya/Tanzania) to independent data for lake mixing and water-column chemistry. These factors influence the GDGT proxies in the earliest depositional phases (before ~180 ka), confounding the climate signal.
Jingjing Guo, Martin Ziegler, Louise Fuchs, Youbin Sun, and Francien Peterse
EGUsphere, https://doi.org/10.5194/egusphere-2024-1648, https://doi.org/10.5194/egusphere-2024-1648, 2024
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In this study, we use the distribution of soil bacterial membrane lipids stored on the Chinese Loess Plateau (CLP) to quantitatively reconstruct variations in precipitation amount over the past 130 kyr. The precipitation record shows orbital- and millennial-scale variations and varies at precession and obliquity scale. The application of this precipitation proxy across the CLP indicates a more pronounced spatial gradient during glacials, when the western CLP experiences more arid conditions.
Marci M. Robinson, Kenneth G. Miller, Tali L. Babila, Timothy J. Bralower, James V. Browning, Marlow J. Cramwinckel, Monika Doubrawa, Gavin L. Foster, Megan K. Fung, Sean Kinney, Maria Makarova, Peter P. McLaughlin, Paul N. Pearson, Ursula Röhl, Morgan F. Schaller, Jean M. Self-Trail, Appy Sluijs, Thomas Westerhold, James D. Wright, and James C. Zachos
Sci. Dril., 33, 47–65, https://doi.org/10.5194/sd-33-47-2024, https://doi.org/10.5194/sd-33-47-2024, 2024
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The Paleocene–Eocene Thermal Maximum (PETM) is the closest geological analog to modern anthropogenic CO2 emissions, but its causes and the responses remain enigmatic. Coastal plain sediments can resolve this uncertainty, but their discontinuous nature requires numerous sites to constrain events. Workshop participants identified 10 drill sites that target the PETM and other interesting intervals. Our post-drilling research will provide valuable insights into Earth system responses.
Peter K. Bijl
Earth Syst. Sci. Data, 16, 1447–1452, https://doi.org/10.5194/essd-16-1447-2024, https://doi.org/10.5194/essd-16-1447-2024, 2024
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This new version release of DINOSTRAT, version 2.1, aligns stratigraphic ranges of dinoflagellate cysts (dinocysts), a microfossil group, to the latest Geologic Time Scale. In this release I present the evolution of dinocyst subfamilies from the Middle Triassic to the modern period.
Alice R. Paine, Isabel M. Fendley, Joost Frieling, Tamsin A. Mather, Jack H. Lacey, Bernd Wagner, Stuart A. Robinson, David M. Pyle, Alexander Francke, Theodore R. Them II, and Konstantinos Panagiotopoulos
Biogeosciences, 21, 531–556, https://doi.org/10.5194/bg-21-531-2024, https://doi.org/10.5194/bg-21-531-2024, 2024
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Many important processes within the global mercury (Hg) cycle operate over thousands of years. Here, we explore the timing, magnitude, and expression of Hg signals retained in sediments of lakes Prespa and Ohrid over the past ∼90 000 years. Divergent signals suggest that local differences in sediment composition, lake structure, and water balance influence the local Hg cycle and determine the extent to which sedimentary Hg signals reflect local- or global-scale environmental changes.
Michiel Baatsen, Peter Bijl, Anna von der Heydt, Appy Sluijs, and Henk Dijkstra
Clim. Past, 20, 77–90, https://doi.org/10.5194/cp-20-77-2024, https://doi.org/10.5194/cp-20-77-2024, 2024
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This work introduces the possibility and consequences of monsoons on Antarctica in the warm Eocene climate. We suggest that such a monsoonal climate can be important to understand conditions in Antarctica prior to large-scale glaciation. We can explain seemingly contradictory indications of ice and vegetation on the continent through regional variability. In addition, we provide a new mechanism through which most of Antarctica remained ice-free through a wide range of global climatic changes.
Maria Elena Gastaldello, Claudia Agnini, and Laia Alegret
J. Micropalaeontol., 43, 1–35, https://doi.org/10.5194/jm-43-1-2024, https://doi.org/10.5194/jm-43-1-2024, 2024
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This paper examines benthic foraminifera, single-celled organisms, at Integrated Ocean Drilling Program Site U1506 in the Tasman Sea from the Late Miocene to the Early Pliocene (between 7.4 to 4.5 million years ago). We described and illustrated the 36 most common species; analysed the past ocean depth of the site; and investigated the environmental conditions at the seafloor during the Biogenic Bloom phenomenon, a global phase of high marine primary productivity.
Madeleine L. Vickers, Morgan T. Jones, Jack Longman, David Evans, Clemens V. Ullmann, Ella Wulfsberg Stokke, Martin Vickers, Joost Frieling, Dustin T. Harper, Vincent J. Clementi, and IODP Expedition 396 Scientists
Clim. Past, 20, 1–23, https://doi.org/10.5194/cp-20-1-2024, https://doi.org/10.5194/cp-20-1-2024, 2024
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The discovery of cold-water glendonite pseudomorphs in sediments deposited during the hottest part of the Cenozoic poses an apparent climate paradox. This study examines their occurrence, association with volcanic sediments, and speculates on the timing and extent of cooling, fitting this with current understanding of global climate during this period. We propose that volcanic activity was key to both physical and chemical conditions that enabled the formation of glendonites in these sediments.
Peter K. Bijl and Henk Brinkhuis
J. Micropalaeontol., 42, 309–314, https://doi.org/10.5194/jm-42-309-2023, https://doi.org/10.5194/jm-42-309-2023, 2023
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We developed an online, open-access database for taxonomic descriptions, stratigraphic information and images of organic-walled dinoflagellate cyst species. With this new resource for applied and academic research, teaching and training, we open up organic-walled dinoflagellate cysts for the academic era of open science. We expect that palsys.org represents a starting point to improve taxonomic concepts, and we invite the community to contribute.
Joost Frieling, Linda van Roij, Iris Kleij, Gert-Jan Reichart, and Appy Sluijs
Biogeosciences, 20, 4651–4668, https://doi.org/10.5194/bg-20-4651-2023, https://doi.org/10.5194/bg-20-4651-2023, 2023
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We present a first species-specific evaluation of marine core-top dinoflagellate cyst carbon isotope fractionation (εp) to assess natural pCO2 dependency on εp and explore its geological deep-time paleo-pCO2 proxy potential. We find that εp differs between genera and species and that in Operculodinium centrocarpum, εp is controlled by pCO2 and nutrients. Our results highlight the added value of δ13C analyses of individual micrometer-scale sedimentary organic carbon particles.
Yord W. Yedema, Timme Donders, Francien Peterse, and Francesca Sangiorgi
J. Micropalaeontol., 42, 257–276, https://doi.org/10.5194/jm-42-257-2023, https://doi.org/10.5194/jm-42-257-2023, 2023
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The pollen and dinoflagellate cyst content of 21 surface sediments from the northern Gulf of Mexico is used to test the applicability of three palynological ratios (heterotroph/autotroph, pollen/dinocyst, and pollen/bisaccate ratio) as proxies for marine productivity and distance to the coast/river. Redundancy analysis confirms the suitability of these three ratios, where the H/A ratio can be used as an indicator of primary production, and the P/B ratio best tracks the distance to the coast.
Stephen P. Hesselbo, Aisha Al-Suwaidi, Sarah J. Baker, Giorgia Ballabio, Claire M. Belcher, Andrew Bond, Ian Boomer, Remco Bos, Christian J. Bjerrum, Kara Bogus, Richard Boyle, James V. Browning, Alan R. Butcher, Daniel J. Condon, Philip Copestake, Stuart Daines, Christopher Dalby, Magret Damaschke, Susana E. Damborenea, Jean-Francois Deconinck, Alexander J. Dickson, Isabel M. Fendley, Calum P. Fox, Angela Fraguas, Joost Frieling, Thomas A. Gibson, Tianchen He, Kat Hickey, Linda A. Hinnov, Teuntje P. Hollaar, Chunju Huang, Alexander J. L. Hudson, Hugh C. Jenkyns, Erdem Idiz, Mengjie Jiang, Wout Krijgsman, Christoph Korte, Melanie J. Leng, Timothy M. Lenton, Katharina Leu, Crispin T. S. Little, Conall MacNiocaill, Miguel O. Manceñido, Tamsin A. Mather, Emanuela Mattioli, Kenneth G. Miller, Robert J. Newton, Kevin N. Page, József Pálfy, Gregory Pieńkowski, Richard J. Porter, Simon W. Poulton, Alberto C. Riccardi, James B. Riding, Ailsa Roper, Micha Ruhl, Ricardo L. Silva, Marisa S. Storm, Guillaume Suan, Dominika Szűcs, Nicolas Thibault, Alfred Uchman, James N. Stanley, Clemens V. Ullmann, Bas van de Schootbrugge, Madeleine L. Vickers, Sonja Wadas, Jessica H. Whiteside, Paul B. Wignall, Thomas Wonik, Weimu Xu, Christian Zeeden, and Ke Zhao
Sci. Dril., 32, 1–25, https://doi.org/10.5194/sd-32-1-2023, https://doi.org/10.5194/sd-32-1-2023, 2023
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We present initial results from a 650 m long core of Late Triasssic to Early Jurassic (190–202 Myr) sedimentary strata from the Cheshire Basin, UK, which is shown to be an exceptional record of Earth evolution for the time of break-up of the supercontinent Pangaea. Further work will determine periodic changes in depositional environments caused by solar system dynamics and used to reconstruct orbital history.
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.
William Rush, Jean Self-Trail, Yang Zhang, Appy Sluijs, Henk Brinkhuis, James Zachos, James G. Ogg, and Marci Robinson
Clim. Past, 19, 1677–1698, https://doi.org/10.5194/cp-19-1677-2023, https://doi.org/10.5194/cp-19-1677-2023, 2023
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The Eocene contains several brief warming periods referred to as hyperthermals. Studying these events and how they varied between locations can help provide insight into our future warmer world. This study provides a characterization of two of these events in the mid-Atlantic region of the USA. The records of climate that we measured demonstrate significant changes during this time period, but the type and timing of these changes highlight the complexity of climatic changes.
Morgan T. Jones, Ella W. Stokke, Alan D. Rooney, Joost Frieling, Philip A. E. Pogge von Strandmann, David J. Wilson, Henrik H. Svensen, Sverre Planke, Thierry Adatte, Nicolas Thibault, Madeleine L. Vickers, Tamsin A. Mather, Christian Tegner, Valentin Zuchuat, and Bo P. Schultz
Clim. Past, 19, 1623–1652, https://doi.org/10.5194/cp-19-1623-2023, https://doi.org/10.5194/cp-19-1623-2023, 2023
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There are periods in Earth’s history when huge volumes of magma are erupted at the Earth’s surface. The gases released from volcanic eruptions and from sediments heated by the magma are believed to have caused severe climate changes in the geological past. We use a variety of volcanic and climatic tracers to assess how the North Atlantic Igneous Province (56–54 Ma) affected the oceans and atmosphere during a period of extreme global warming.
Peter K. Bijl
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2023-169, https://doi.org/10.5194/essd-2023-169, 2023
Publication in ESSD not foreseen
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This new version release of DINOSTRAT, version 2.0, aligns stratigraphic ranges of dinoflagellate cysts, a microfossil group, to the Geologic Time Scale. In this release we present the evolution of dinocyst subfamilies from the mid-Triassic to the modern.
Lena Mareike Thöle, Peter Dirk Nooteboom, Suning Hou, Rujian Wang, Senyan Nie, Elisabeth Michel, Isabel Sauermilch, Fabienne Marret, Francesca Sangiorgi, and Peter Kristian Bijl
J. Micropalaeontol., 42, 35–56, https://doi.org/10.5194/jm-42-35-2023, https://doi.org/10.5194/jm-42-35-2023, 2023
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Dinoflagellate cysts can be used to infer past oceanographic conditions in the Southern Ocean. This requires knowledge of their present-day ecologic affinities. We add 66 Antarctic-proximal surface sediment samples to the Southern Ocean data and derive oceanographic conditions at those stations. Dinoflagellate cysts are clearly biogeographically separated along latitudinal gradients of temperature, sea ice, nutrients, and salinity, which allows us to reconstruct these parameters for the past.
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.
Yord W. Yedema, Francesca Sangiorgi, Appy Sluijs, Jaap S. Sinninghe Damsté, and Francien Peterse
Biogeosciences, 20, 663–686, https://doi.org/10.5194/bg-20-663-2023, https://doi.org/10.5194/bg-20-663-2023, 2023
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Terrestrial organic matter (TerrOM) is transported to the ocean by rivers, where its burial can potentially form a long-term carbon sink. This burial is dependent on the type and characteristics of the TerrOM. We used bulk sediment properties, biomarkers, and palynology to identify the dispersal patterns of plant-derived, soil–microbial, and marine OM in the northern Gulf of Mexico and show that plant-derived OM is transported further into the coastal zone than soil and marine-produced TerrOM.
Frédérique M. S. A. Kirkels, Hugo J. de Boer, Paulina Concha Hernández, Chris R. T. Martes, Marcel T. J. van der Meer, Sayak Basu, Muhammed O. Usman, and Francien Peterse
Biogeosciences, 19, 4107–4127, https://doi.org/10.5194/bg-19-4107-2022, https://doi.org/10.5194/bg-19-4107-2022, 2022
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The distinct carbon isotopic values of C3 and C4 plants are widely used to reconstruct past hydroclimate, where more C3 plants reflect wetter and C4 plants drier conditions. Here we examine the impact of regional hydroclimatic conditions on plant isotopic values in the Godavari River basin, India. We find that it is crucial to identify regional plant isotopic values and consider drought stress, which introduces a bias in C3 / C4 plant estimates and associated hydroclimate reconstructions.
Frédérique M. S. A. Kirkels, Huub M. Zwart, Muhammed O. Usman, Suning Hou, Camilo Ponton, Liviu Giosan, Timothy I. Eglinton, and Francien Peterse
Biogeosciences, 19, 3979–4010, https://doi.org/10.5194/bg-19-3979-2022, https://doi.org/10.5194/bg-19-3979-2022, 2022
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Soil organic carbon (SOC) that is transferred to the ocean by rivers forms a long-term sink of atmospheric CO2 upon burial on the ocean floor. We here test if certain bacterial membrane lipids can be used to trace SOC through the monsoon-fed Godavari River basin in India. We find that these lipids trace the mobilisation and transport of SOC in the wet season but that these lipids are not transferred far into the sea. This suggests that the burial of SOC on the sea floor is limited here.
Carolien M. H. van der Weijst, Koen J. van der Laan, Francien Peterse, Gert-Jan Reichart, Francesca Sangiorgi, Stefan Schouten, Tjerk J. T. Veenstra, and Appy Sluijs
Clim. Past, 18, 1947–1962, https://doi.org/10.5194/cp-18-1947-2022, https://doi.org/10.5194/cp-18-1947-2022, 2022
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The TEX86 proxy is often used by paleoceanographers to reconstruct past sea-surface temperatures. However, the origin of the TEX86 signal in marine sediments has been debated since the proxy was first proposed. In our paper, we show that TEX86 carries a mixed sea-surface and subsurface temperature signal and should be calibrated accordingly. Using our 15-million-year record, we subsequently show how a TEX86 subsurface temperature record can be used to inform us on past sea-surface temperatures.
Karen M. Brandenburg, Björn Rost, Dedmer B. Van de Waal, Mirja Hoins, and Appy Sluijs
Biogeosciences, 19, 3305–3315, https://doi.org/10.5194/bg-19-3305-2022, https://doi.org/10.5194/bg-19-3305-2022, 2022
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Reconstructions of past CO2 concentrations rely on proxy estimates, with one line of proxies relying on the CO2-dependence of stable carbon isotope fractionation in marine phytoplankton. Culturing experiments provide insights into which processes may impact this. We found, however, that the methods with which these culturing experiments are performed also influence 13C fractionation. Caution should therefore be taken when extrapolating results from these experiments to proxy applications.
Carolien M. H. van der Weijst, Josse Winkelhorst, Wesley de Nooijer, Anna von der Heydt, Gert-Jan Reichart, Francesca Sangiorgi, and Appy Sluijs
Clim. Past, 18, 961–973, https://doi.org/10.5194/cp-18-961-2022, https://doi.org/10.5194/cp-18-961-2022, 2022
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A hypothesized link between Pliocene (5.3–2.5 million years ago) global climate and tropical thermocline depth is currently only backed up by data from the Pacific Ocean. In our paper, we present temperature, salinity, and thermocline records from the tropical Atlantic Ocean. Surprisingly, the Pliocene thermocline evolution was remarkably different in the Atlantic and Pacific. We need to reevaluate the mechanisms that drive thermocline depth, and how these are tied to global climate change.
Michael Amoo, Ulrich Salzmann, Matthew J. Pound, Nick Thompson, and Peter K. Bijl
Clim. Past, 18, 525–546, https://doi.org/10.5194/cp-18-525-2022, https://doi.org/10.5194/cp-18-525-2022, 2022
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Late Eocene to earliest Oligocene (37.97–33.06 Ma) climate and vegetation dynamics around the Tasmanian Gateway region reveal that changes in ocean circulation due to accelerated deepening of the Tasmanian Gateway may not have been solely responsible for the changes in terrestrial climate and vegetation; a series of regional and global events, including a change in stratification of water masses and changes in pCO2, may have played significant roles.
Peter D. Nooteboom, Peter K. Bijl, Christian Kehl, Erik van Sebille, Martin Ziegler, Anna S. von der Heydt, and Henk A. Dijkstra
Earth Syst. Dynam., 13, 357–371, https://doi.org/10.5194/esd-13-357-2022, https://doi.org/10.5194/esd-13-357-2022, 2022
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Having descended through the water column, microplankton in ocean sediments represents the ocean surface environment and is used as an archive of past and present surface oceanographic conditions. However, this microplankton is advected by turbulent ocean currents during its sinking journey. We use simulations of sinking particles to define ocean bottom provinces and detect these provinces in datasets of sedimentary microplankton, which has implications for palaeoclimate reconstructions.
Peter K. Bijl
Earth Syst. Sci. Data, 14, 579–617, https://doi.org/10.5194/essd-14-579-2022, https://doi.org/10.5194/essd-14-579-2022, 2022
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Using microfossils to gauge the age of rocks and sediments requires an accurate age of their first (origination) and last (extinction) appearances. But how do you know such ages can then be applied worldwide? And what causes regional differences? This paper investigates the regional consistency of ranges of species of a specific microfossil group, organic-walled dinoflagellate cysts. This overview helps in identifying regional differences in the stratigraphic ranges of species and their causes.
Nick Thompson, Ulrich Salzmann, Adrián López-Quirós, Peter K. Bijl, Frida S. Hoem, Johan Etourneau, Marie-Alexandrine Sicre, Sabine Roignant, Emma Hocking, Michael Amoo, and Carlota Escutia
Clim. Past, 18, 209–232, https://doi.org/10.5194/cp-18-209-2022, https://doi.org/10.5194/cp-18-209-2022, 2022
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New pollen and spore data from the Antarctic Peninsula region reveal temperate rainforests that changed and adapted in response to Eocene climatic cooling, roughly 35.5 Myr ago, and glacially related disturbance in the early Oligocene, approximately 33.5 Myr ago. The timing of these events indicates that the opening of ocean gateways alone did not trigger Antarctic glaciation, although ocean gateways may have played a role in climate cooling.
Peter K. Bijl, Joost Frieling, Marlow Julius Cramwinckel, Christine Boschman, Appy Sluijs, and Francien Peterse
Clim. Past, 17, 2393–2425, https://doi.org/10.5194/cp-17-2393-2021, https://doi.org/10.5194/cp-17-2393-2021, 2021
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Here, we use the latest insights for GDGT and dinocyst-based paleotemperature and paleoenvironmental reconstructions in late Cretaceous–early Oligocene sediments from ODP Site 1172 (East Tasman Plateau, Australia). We reconstruct strong river runoff during the Paleocene–early Eocene, a progressive decline thereafter with increased wet/dry seasonality in the northward-drifting hinterland. Our critical review leaves the anomalous warmth of the Eocene SW Pacific Ocean unexplained.
Frida S. Hoem, Isabel Sauermilch, Suning Hou, Henk Brinkhuis, Francesca Sangiorgi, and Peter K. Bijl
J. Micropalaeontol., 40, 175–193, https://doi.org/10.5194/jm-40-175-2021, https://doi.org/10.5194/jm-40-175-2021, 2021
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We use marine microfossil (dinocyst) assemblage data as well as seismic and tectonic investigations to reconstruct the oceanographic history south of Australia 37–20 Ma as the Tasmanian Gateway widens and deepens. Our results show stable conditions with typically warmer dinocysts south of Australia, which contrasts with the colder dinocysts closer to Antarctica, indicating the establishment of modern oceanographic conditions with a strong Southern Ocean temperature gradient and frontal systems.
Gerrit Müller, Jack J. Middelburg, and Appy Sluijs
Earth Syst. Sci. Data, 13, 3565–3575, https://doi.org/10.5194/essd-13-3565-2021, https://doi.org/10.5194/essd-13-3565-2021, 2021
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Rivers are major freshwater resources, connectors and transporters on Earth. As the composition of river waters and particles results from processes in their catchment, such as erosion, weathering, environmental pollution, nutrient and carbon cycling, Earth-spanning databases of river composition are needed for studies of these processes on a global scale. While extensive resources on water and nutrient composition exist, we provide a database of river particle composition.
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.
Niels J. de Winter, Tobias Agterhuis, and Martin Ziegler
Clim. Past, 17, 1315–1340, https://doi.org/10.5194/cp-17-1315-2021, https://doi.org/10.5194/cp-17-1315-2021, 2021
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Climate researchers often need to compromise in their sampling between increasing the number of measurements to obtain higher time resolution and combining measurements to improve the reliability of climate reconstructions. In this study, we test several methods for achieving the optimal balance between these competing interests by simulating seasonality reconstructions using stable and clumped isotopes. Our results inform sampling strategies for climate reconstructions in general.
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.
Annique van der Boon, Klaudia F. Kuiper, Robin van der Ploeg, Marlow Julius Cramwinckel, Maryam Honarmand, Appy Sluijs, and Wout Krijgsman
Clim. Past, 17, 229–239, https://doi.org/10.5194/cp-17-229-2021, https://doi.org/10.5194/cp-17-229-2021, 2021
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40.5 million years ago, Earth's climate warmed, but it is unknown why. Enhanced volcanism has been suggested, but this has not yet been tied to a specific region. We explore an increase in volcanism in Iran. We dated igneous rocks and compiled ages from the literature. We estimated the volume of igneous rocks in Iran in order to calculate the amount of CO2 that could have been released due to enhanced volcanism. We conclude that an increase in volcanism in Iran is a plausible cause of warming.
Daniel J. Lunt, Fran Bragg, Wing-Le Chan, David K. Hutchinson, Jean-Baptiste Ladant, Polina Morozova, Igor Niezgodzki, Sebastian Steinig, Zhongshi Zhang, Jiang Zhu, Ayako Abe-Ouchi, Eleni Anagnostou, Agatha M. de Boer, Helen K. Coxall, Yannick Donnadieu, Gavin Foster, Gordon N. Inglis, Gregor Knorr, Petra M. Langebroek, Caroline H. Lear, Gerrit Lohmann, Christopher J. Poulsen, Pierre Sepulchre, Jessica E. Tierney, Paul J. Valdes, Evgeny M. Volodin, Tom Dunkley Jones, Christopher J. Hollis, Matthew Huber, and Bette L. Otto-Bliesner
Clim. Past, 17, 203–227, https://doi.org/10.5194/cp-17-203-2021, https://doi.org/10.5194/cp-17-203-2021, 2021
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This paper presents the first modelling results from the Deep-Time Model Intercomparison Project (DeepMIP), in which we focus on the early Eocene climatic optimum (EECO, 50 million years ago). We show that, in contrast to previous work, at least three models (CESM, GFDL, and NorESM) produce climate states that are consistent with proxy indicators of global mean temperature and polar amplification, and they achieve this at a CO2 concentration that is consistent with the CO2 proxy record.
Michiel Baatsen, Anna S. von der Heydt, Matthew Huber, Michael A. Kliphuis, Peter K. Bijl, Appy Sluijs, and Henk A. Dijkstra
Clim. Past, 16, 2573–2597, https://doi.org/10.5194/cp-16-2573-2020, https://doi.org/10.5194/cp-16-2573-2020, 2020
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Warm climates of the deep past have proven to be challenging to reconstruct with the same numerical models used for future predictions. We present results of CESM simulations for the middle to late Eocene (∼ 38 Ma), in which we managed to match the available indications of temperature well. With these results we can now look into regional features and the response to external changes to ultimately better understand the climate when it is in such a warm state.
Appy Sluijs, Joost Frieling, Gordon N. Inglis, Klaas G. J. Nierop, Francien Peterse, Francesca Sangiorgi, and Stefan Schouten
Clim. Past, 16, 2381–2400, https://doi.org/10.5194/cp-16-2381-2020, https://doi.org/10.5194/cp-16-2381-2020, 2020
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We revisit 15-year-old reconstructions of sea surface temperatures in the Arctic Ocean for the late Paleocene and early Eocene epochs (∼ 57–53 million years ago) based on the distribution of fossil membrane lipids of archaea preserved in Arctic Ocean sediments. We find that improvements in the methods over the past 15 years do not lead to different results. However, data quality is now higher and potential biases better characterized. Results confirm remarkable Arctic warmth during this time.
Loes G. J. van Bree, Francien Peterse, Allix J. Baxter, Wannes De Crop, Sigrid van Grinsven, Laura Villanueva, Dirk Verschuren, and Jaap S. Sinninghe Damsté
Biogeosciences, 17, 5443–5463, https://doi.org/10.5194/bg-17-5443-2020, https://doi.org/10.5194/bg-17-5443-2020, 2020
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Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are used as a paleothermometer based on their temperature dependence in global soils, but aquatic production complicates their use in lakes. BrGDGTs in the water column of Lake Chala, East Africa, respond to oxygen conditions and mixing. Changes in their signal can be linked to bacterial community composition rather than membrane adaptation to changing conditions. Their integrated signal in the sediment reflects mean air temperature.
Gordon N. Inglis, Fran Bragg, Natalie J. Burls, Marlow Julius Cramwinckel, David Evans, Gavin L. Foster, Matthew Huber, Daniel J. Lunt, Nicholas Siler, Sebastian Steinig, Jessica E. Tierney, Richard Wilkinson, Eleni Anagnostou, Agatha M. de Boer, Tom Dunkley Jones, Kirsty M. Edgar, Christopher J. Hollis, David K. Hutchinson, and Richard D. Pancost
Clim. Past, 16, 1953–1968, https://doi.org/10.5194/cp-16-1953-2020, https://doi.org/10.5194/cp-16-1953-2020, 2020
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This paper presents estimates of global mean surface temperatures and climate sensitivity during the early Paleogene (∼57–48 Ma). We employ a multi-method experimental approach and show that i) global mean surface temperatures range between 27 and 32°C and that ii) estimates of
bulkequilibrium climate sensitivity (∼3 to 4.5°C) fall within the range predicted by the IPCC AR5 Report. This work improves our understanding of two key climate metrics during the early Paleogene.
Marlow Julius Cramwinckel, Lineke Woelders, Emiel P. Huurdeman, Francien Peterse, Stephen J. Gallagher, Jörg Pross, Catherine E. Burgess, Gert-Jan Reichart, Appy Sluijs, and Peter K. Bijl
Clim. Past, 16, 1667–1689, https://doi.org/10.5194/cp-16-1667-2020, https://doi.org/10.5194/cp-16-1667-2020, 2020
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Phases of past transient warming can be used as a test bed to study the environmental response to climate change independent of tectonic change. Using fossil plankton and organic molecules, here we reconstruct surface ocean temperature and circulation in and around the Tasman Gateway during a warming phase 40 million years ago termed the Middle Eocene Climatic Optimum. We find that plankton assemblages track ocean circulation patterns, with superimposed variability being related to temperature.
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.
Carolien Maria Hendrina van der Weijst, Josse Winkelhorst, Anna von der Heydt, Gert-Jan Reichart, Francesca Sangiorgi, and Appy Sluijs
Clim. Past Discuss., https://doi.org/10.5194/cp-2020-105, https://doi.org/10.5194/cp-2020-105, 2020
Manuscript not accepted for further review
Claudia Agnini, Martha G. Pamato, Gabriella Salviulo, Kim A. Barchi, and Fabrizio Nestola
Adv. Geosci., 53, 155–167, https://doi.org/10.5194/adgeo-53-155-2020, https://doi.org/10.5194/adgeo-53-155-2020, 2020
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This work provides updated scenario on the underrepresentation of women in the Italian university system in the area of geosciences in the last two decades. Data highlight an increase in the number of female full and associate professors whereas the low number of female non-permanent researchers raises strong concerns. Over different areas of geosciences, Paleontology represents the only field in which the gap is filled whereas all the other disciplines suffer a gender imbalance.
Jingjing Guo, Miriam Glendell, Jeroen Meersmans, Frédérique Kirkels, Jack J. Middelburg, and Francien Peterse
Biogeosciences, 17, 3183–3201, https://doi.org/10.5194/bg-17-3183-2020, https://doi.org/10.5194/bg-17-3183-2020, 2020
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The fluxes of soil organic carbon (OC) transport from land to sea are poorly constrained, mostly due to the lack of a specific tracer for soil OC. Here we evaluate the use of specific molecules derived from soil bacteria as a tracer for soil OC in a small river catchment. We find that the initial soil signal is lost upon entering the aquatic environment. However, the local environmental history of the catchment is reflected by these molecules in the lake sediments that act as their sink.
Alan T. Kennedy-Asser, Daniel J. Lunt, Paul J. Valdes, Jean-Baptiste Ladant, Joost Frieling, and Vittoria Lauretano
Clim. Past, 16, 555–573, https://doi.org/10.5194/cp-16-555-2020, https://doi.org/10.5194/cp-16-555-2020, 2020
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Global cooling and a major expansion of ice over Antarctica occurred ~ 34 million years ago at the Eocene–Oligocene transition (EOT). A large secondary proxy dataset for high-latitude Southern Hemisphere temperature before, after and across the EOT is compiled and compared to simulations from two coupled climate models. Although there are inconsistencies between the models and data, the comparison shows amongst other things that changes in the Drake Passage were unlikely the cause of the EOT.
Emily Dearing Crampton-Flood, Lars J. Noorbergen, Damian Smits, R. Christine Boschman, Timme H. Donders, Dirk K. Munsterman, Johan ten Veen, Francien Peterse, Lucas Lourens, and Jaap S. Sinninghe Damsté
Clim. Past, 16, 523–541, https://doi.org/10.5194/cp-16-523-2020, https://doi.org/10.5194/cp-16-523-2020, 2020
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The mid-Pliocene warm period (mPWP; 3.3–3.0 million years ago) is thought to be the last geological interval with similar atmospheric carbon dioxide concentrations as the present day. Further, the mPWP was 2–3 °C warmer than present, making it a good analogue for estimating the effects of future climate change. Here, we construct a new precise age model for the North Sea during the mPWP, and provide a detailed reconstruction of terrestrial and marine climate using a multi-proxy approach.
Gabriel J. Bowen, Brenden Fischer-Femal, Gert-Jan Reichart, Appy Sluijs, and Caroline H. Lear
Clim. Past, 16, 65–78, https://doi.org/10.5194/cp-16-65-2020, https://doi.org/10.5194/cp-16-65-2020, 2020
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Past climate conditions are reconstructed using indirect and incomplete geological, biological, and geochemical proxy data. We propose that such reconstructions are best obtained by statistical inversion of hierarchical models that represent how multi–proxy observations and calibration data are produced by variation of environmental conditions in time and/or space. These methods extract new information from traditional proxies and provide robust, comprehensive estimates of uncertainty.
Christian Berndt, Sverre Planke, Damon Teagle, Ritske Huismans, Trond Torsvik, Joost Frieling, Morgan T. Jones, Dougal A. Jerram, Christian Tegner, Jan Inge Faleide, Helen Coxall, and Wei-Li Hong
Sci. Dril., 26, 69–85, https://doi.org/10.5194/sd-26-69-2019, https://doi.org/10.5194/sd-26-69-2019, 2019
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The northeast Atlantic encompasses archetypal examples of volcanic rifted margins. Twenty-five years after the last ODP leg on these volcanic margins, the reasons for excess melting are still disputed with at least three competing hypotheses being discussed. We are proposing a new drilling campaign that will constrain the timing, rates of volcanism, and vertical movements of rifted margins.
Johan Vellekoop, Lineke Woelders, Appy Sluijs, Kenneth G. Miller, and Robert P. Speijer
Biogeosciences, 16, 4201–4210, https://doi.org/10.5194/bg-16-4201-2019, https://doi.org/10.5194/bg-16-4201-2019, 2019
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Our micropaleontological analyses on three cores from New Jersey (USA) show that the late Maastrichtian warming event (66.4–66.1 Ma), characterized by a ~ 4.0 °C warming of sea waters on the New Jersey paleoshelf, resulted in a disruption of phytoplankton communities and a stressed benthic ecosystem. This increased ecosystem stress during the latest Maastrichtian potentially primed global ecosystems for the subsequent mass extinction following the Cretaceous–Paleogene boundary impact.
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.
Charlotte Miller, Jemma Finch, Trevor Hill, Francien Peterse, Marc Humphries, Matthias Zabel, and Enno Schefuß
Clim. Past, 15, 1153–1170, https://doi.org/10.5194/cp-15-1153-2019, https://doi.org/10.5194/cp-15-1153-2019, 2019
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Here we reconstruct vegetation and precipitation, in eastern South Africa, over the last 32 000 years, by measuring the stable carbon and hydrogen isotope composition of plant waxes from Mfabeni peat bog (KwaZulu-Natal). Our results indicate that the late Quaternary climate in eastern South Africa did not respond directly to orbital forcing or to changes in sea-surface temperatures. Our findings stress the influence of the Southern Hemisphere westerlies in driving climate change in the region.
Morgan T. Jones, Lawrence M. E. Percival, Ella W. Stokke, Joost Frieling, Tamsin A. Mather, Lars Riber, Brian A. Schubert, Bo Schultz, Christian Tegner, Sverre Planke, and Henrik H. Svensen
Clim. Past, 15, 217–236, https://doi.org/10.5194/cp-15-217-2019, https://doi.org/10.5194/cp-15-217-2019, 2019
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Mercury anomalies in sedimentary rocks are used to assess whether there were periods of elevated volcanism in the geological record. We focus on five sites that cover the Palaeocene–Eocene Thermal Maximum, an extreme global warming event that occurred 55.8 million years ago. We find that sites close to the eruptions from the North Atlantic Igneous Province display significant mercury anomalies across this time interval, suggesting that magmatism played a role in the global warming event.
Ilja J. Kocken, Marlow Julius Cramwinckel, Richard E. Zeebe, Jack J. Middelburg, and Appy Sluijs
Clim. Past, 15, 91–104, https://doi.org/10.5194/cp-15-91-2019, https://doi.org/10.5194/cp-15-91-2019, 2019
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Marine organic carbon burial could link the 405 thousand year eccentricity cycle in the long-term carbon cycle to that observed in climate records. Here, we simulate the response of the carbon cycle to astronomical forcing. We find a strong 2.4 million year cycle in the model output, which is present as an amplitude modulator of the 405 and 100 thousand year eccentricity cycles in a newly assembled composite record.
Robert McKay, Neville Exon, Dietmar Müller, Karsten Gohl, Michael Gurnis, Amelia Shevenell, Stuart Henrys, Fumio Inagaki, Dhananjai Pandey, Jessica Whiteside, Tina van de Flierdt, Tim Naish, Verena Heuer, Yuki Morono, Millard Coffin, Marguerite Godard, Laura Wallace, Shuichi Kodaira, Peter Bijl, Julien Collot, Gerald Dickens, Brandon Dugan, Ann G. Dunlea, Ron Hackney, Minoru Ikehara, Martin Jutzeler, Lisa McNeill, Sushant Naik, Taryn Noble, Bradley Opdyke, Ingo Pecher, Lowell Stott, Gabriele Uenzelmann-Neben, Yatheesh Vadakkeykath, and Ulrich G. Wortmann
Sci. Dril., 24, 61–70, https://doi.org/10.5194/sd-24-61-2018, https://doi.org/10.5194/sd-24-61-2018, 2018
Loeka L. Jongejans, Jens Strauss, Josefine Lenz, Francien Peterse, Kai Mangelsdorf, Matthias Fuchs, and Guido Grosse
Biogeosciences, 15, 6033–6048, https://doi.org/10.5194/bg-15-6033-2018, https://doi.org/10.5194/bg-15-6033-2018, 2018
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Arctic warming mobilizes belowground organic matter in northern high latitudes. This study focused on the size of organic carbon pools and organic matter quality in ice-rich permafrost on the Baldwin Peninsula, West Alaska. We analyzed biogeochemistry and found that three-quarters of the carbon is stored in degraded permafrost deposits. Nonetheless, using biomarker analyses, we showed that the organic matter in undisturbed yedoma permafrost has a higher potential for decomposition.
Julian D. Hartman, Peter K. Bijl, and Francesca Sangiorgi
J. Micropalaeontol., 37, 445–497, https://doi.org/10.5194/jm-37-445-2018, https://doi.org/10.5194/jm-37-445-2018, 2018
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We present an extensive overview of the organic microfossil remains found at Site U1357, Adélie Basin, East Antarctica. The organic microfossil remains are exceptionally well preserved and are derived from unicellular as well as higher organisms. We provide a morphological description, photographic images, and a discussion of the ecological preferences of the biological species from which the organic remains were derived.
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.
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.
Julie Lattaud, Frédérique Kirkels, Francien Peterse, Chantal V. Freymond, Timothy I. Eglinton, Jens Hefter, Gesine Mollenhauer, Sergio Balzano, Laura Villanueva, Marcel T. J. van der Meer, Ellen C. Hopmans, Jaap S. Sinninghe Damsté, and Stefan Schouten
Biogeosciences, 15, 4147–4161, https://doi.org/10.5194/bg-15-4147-2018, https://doi.org/10.5194/bg-15-4147-2018, 2018
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Long-chain diols (LCDs) are biomarkers that occur widespread in marine environments and also in lakes and rivers. In this study, we looked at the distribution of LCDs in three river systems (Godavari, Danube, and Rhine) in relation to season, precipitation, and temperature. We found out that the LCDs are likely being produced in calm areas of the river systems and that marine LCDs have a different distribution than riverine LCDs.
Muhammed Ojoshogu Usman, Frédérique Marie Sophie Anne Kirkels, Huub Michel Zwart, Sayak Basu, Camilo Ponton, Thomas Michael Blattmann, Michael Ploetze, Negar Haghipour, Cameron McIntyre, Francien Peterse, Maarten Lupker, Liviu Giosan, and Timothy Ian Eglinton
Biogeosciences, 15, 3357–3375, https://doi.org/10.5194/bg-15-3357-2018, https://doi.org/10.5194/bg-15-3357-2018, 2018
Michiel Baatsen, Anna S. von der Heydt, Matthew Huber, Michael A. Kliphuis, Peter K. Bijl, Appy Sluijs, and Henk A. Dijkstra
Clim. Past Discuss., https://doi.org/10.5194/cp-2018-43, https://doi.org/10.5194/cp-2018-43, 2018
Revised manuscript not accepted
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The Eocene marks a period where the climate was in a hothouse state, without any continental-scale ice sheets. Such climates have proven difficult to reproduce in models, especially their low temperature difference between equator and poles. Here, we present high resolution CESM simulations using a new geographic reconstruction of the middle-to-late Eocene. The results provide new insights into a period for which knowledge is limited, leading up to a transition into the present icehouse state.
Timme H. Donders, Niels A. G. M. van Helmond, Roel Verreussel, Dirk Munsterman, Johan ten Veen, Robert P. Speijer, Johan W. H. Weijers, Francesca Sangiorgi, Francien Peterse, Gert-Jan Reichart, Jaap S. Sinninghe Damsté, Lucas Lourens, Gesa Kuhlmann, and Henk Brinkhuis
Clim. Past, 14, 397–411, https://doi.org/10.5194/cp-14-397-2018, https://doi.org/10.5194/cp-14-397-2018, 2018
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The buildup and melting of ice during the early glaciations in the Northern Hemisphere, around 2.5 million years ago, were far shorter in duration than during the last million years. Based on molecular compounds and microfossils from sediments dating back to the early glaciations we show that the temperature on land and in the sea changed simultaneously and was a major factor in the ice buildup in the Northern Hemisphere. These data provide key insights into the dynamics of early glaciations.
Helen M. Beddow, Diederik Liebrand, Douglas S. Wilson, Frits J. Hilgen, Appy Sluijs, Bridget S. Wade, and Lucas J. Lourens
Clim. Past, 14, 255–270, https://doi.org/10.5194/cp-14-255-2018, https://doi.org/10.5194/cp-14-255-2018, 2018
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We present two astronomy-based timescales for climate records from the Pacific Ocean. These records range from 24 to 22 million years ago, a time period when Earth was warmer than today and the only land ice was located on Antarctica. We use tectonic plate-pair spreading rates to test the two timescales, which shows that the carbonate record yields the best timescale. In turn, this implies that Earth’s climate system and carbon cycle responded slowly to changes in incoming solar radiation.
Joost Frieling, Emiel P. Huurdeman, Charlotte C. M. Rem, Timme H. Donders, Jörg Pross, Steven M. Bohaty, Guy R. Holdgate, Stephen J. Gallagher, Brian McGowran, and Peter K. Bijl
J. Micropalaeontol., 37, 317–339, https://doi.org/10.5194/jm-37-317-2018, https://doi.org/10.5194/jm-37-317-2018, 2018
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The hothouse climate of the early Paleogene and the associated violent carbon cycle perturbations are of particular interest to understanding current and future global climate change. Using dinoflagellate cysts and stable carbon isotope analyses, we identify several significant events, e.g., the Paleocene–Eocene Thermal Maximum in sedimentary deposits from the Otway Basin, SE Australia. We anticipate that this study will facilitate detailed climate reconstructions west of the Tasmanian Gateway.
Joost Frieling, Gert-Jan Reichart, Jack J. Middelburg, Ursula Röhl, Thomas Westerhold, Steven M. Bohaty, and Appy Sluijs
Clim. Past, 14, 39–55, https://doi.org/10.5194/cp-14-39-2018, https://doi.org/10.5194/cp-14-39-2018, 2018
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Past periods of rapid global warming such as the Paleocene–Eocene Thermal Maximum are used to study biotic response to climate change. We show that very high peak PETM temperatures in the tropical Atlantic (~ 37 ºC) caused heat stress in several marine plankton groups. However, only slightly cooler temperatures afterwards allowed highly diverse plankton communities to bloom. This shows that tropical plankton communities may be susceptible to extreme warming, but may also recover rapidly.
Peter K. Bijl, Alexander J. P. Houben, Anja Bruls, Jörg Pross, and Francesca Sangiorgi
J. Micropalaeontol., 37, 105–138, https://doi.org/10.5194/jm-37-105-2018, https://doi.org/10.5194/jm-37-105-2018, 2018
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In order to use ocean sediments as a recorder of past oceanographic changes, a critical first step is to stratigraphically date the sediments. The absence of microfossils with known stratigraphic ranges has always hindered dating of Southern Ocean sediments. Here we tie dinocyst ranges to the international timescale in a well-dated sediment core from offshore Antarctica. With this, we can now use dinocysts as a biostratigraphic tool in otherwise stratigraphically poorly dated sediments.
Gary Shaffer, Esteban Fernández Villanueva, Roberto Rondanelli, Jens Olaf Pepke Pedersen, Steffen Malskær Olsen, and Matthew Huber
Geosci. Model Dev., 10, 4081–4103, https://doi.org/10.5194/gmd-10-4081-2017, https://doi.org/10.5194/gmd-10-4081-2017, 2017
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We include methane cycling in the simplified but well-tested Danish Center for Earth System Science model. We now can deal with very large methane inputs to the Earth system that can lead to more methane in the atmosphere, extreme warming and ocean dead zones. We can now study ancient global warming events, probably forced by methane inputs. Some such events were accompanied by mass extinctions. We wish to understand such events, both for learning about the past and for looking into the future.
Thomas Westerhold, Ursula Röhl, Thomas Frederichs, Claudia Agnini, Isabella Raffi, James C. Zachos, and Roy H. Wilkens
Clim. Past, 13, 1129–1152, https://doi.org/10.5194/cp-13-1129-2017, https://doi.org/10.5194/cp-13-1129-2017, 2017
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We assembled a very accurate geological timescale from the interval 47.8 to 56.0 million years ago, also known as the Ypresian stage. We used cyclic variations in the data caused by periodic changes in Earthäs orbit around the sun as a metronome for timescale construction. Our new data compilation provides the first geological evidence for chaos in the long-term behavior of planetary orbits in the solar system, as postulated almost 30 years ago, and a possible link to plate tectonics events.
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.
Michiel Baatsen, Douwe J. J. van Hinsbergen, Anna S. von der Heydt, Henk A. Dijkstra, Appy Sluijs, Hemmo A. Abels, and Peter K. Bijl
Clim. Past, 12, 1635–1644, https://doi.org/10.5194/cp-12-1635-2016, https://doi.org/10.5194/cp-12-1635-2016, 2016
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One of the major difficulties in modelling palaeoclimate is constricting the boundary conditions, causing significant discrepancies between different studies. Here, a new method is presented to automate much of the process of generating the necessary geographical reconstructions. The latter can be made using various rotational frameworks and topography/bathymetry input, allowing for easy inter-comparisons and the incorporation of the latest insights from geoscientific research.
Niels A. G. M. van Helmond, Appy Sluijs, Nina M. Papadomanolaki, A. Guy Plint, Darren R. Gröcke, Martin A. Pearce, James S. Eldrett, João Trabucho-Alexandre, Ireneusz Walaszczyk, Bas van de Schootbrugge, and Henk Brinkhuis
Biogeosciences, 13, 2859–2872, https://doi.org/10.5194/bg-13-2859-2016, https://doi.org/10.5194/bg-13-2859-2016, 2016
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Over the past decades large changes have been observed in the biogeographical dispersion of marine life resulting from climate change. To better understand present and future trends it is important to document and fully understand the biogeographical response of marine life during episodes of environmental change in the geological past.
Here we investigate the response of phytoplankton, the base of the marine food web, to a rapid cold spell, interrupting greenhouse conditions during the Cretaceous.
Valeria Luciani, Gerald R. Dickens, Jan Backman, Eliana Fornaciari, Luca Giusberti, Claudia Agnini, and Roberta D'Onofrio
Clim. Past, 12, 981–1007, https://doi.org/10.5194/cp-12-981-2016, https://doi.org/10.5194/cp-12-981-2016, 2016
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The symbiont-bearing planktic foraminiferal genera Morozovella and Acarinina were among the most important calcifiers of the early Paleogene tropical and subtropical oceans. However, a remarkable and permanent switch in the relative abundance of these genera happened in the early Eocene. We show that this switch occurred at low-latitude sites near the start of the Early Eocene Climatic Optimum (EECO), a multi-million-year interval when Earth surface temperatures reached their Cenozoic maximum.
Claudia Agnini, David J. A. Spofforth, Gerald R. Dickens, Domenico Rio, Heiko Pälike, Jan Backman, Giovanni Muttoni, and Edoardo Dallanave
Clim. Past, 12, 883–909, https://doi.org/10.5194/cp-12-883-2016, https://doi.org/10.5194/cp-12-883-2016, 2016
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In this paper we present records of stable C and O isotopes, CaCO3 content, and changes in calcareous nannofossil assemblages in a upper Paleocene-lower Eocene rocks now exposed in northeast Italy. Modifications of nannoplankton assemblages and carbon isotopes are strictly linked one to each other and always display the same ranking and spacing. The integration of this two data sets represents a significative improvement in our capacity to correlate different sections at a very high resolution.
Willem P. Sijp, Anna S. von der Heydt, and Peter K. Bijl
Clim. Past, 12, 807–817, https://doi.org/10.5194/cp-12-807-2016, https://doi.org/10.5194/cp-12-807-2016, 2016
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The timing and role in ocean circulation and climate of the opening of Southern Ocean gateways is as yet elusive. Here, we present the first model results specific to the early-to-middle Eocene where, in agreement with the field evidence, a southerly shallow opening of the Tasman Gateway does indeed cause a westward flow across the Tasman Gateway, in agreement with recent micropalaeontological studies.
Matthew J. Carmichael, Daniel J. Lunt, Matthew Huber, Malte Heinemann, Jeffrey Kiehl, Allegra LeGrande, Claire A. Loptson, Chris D. Roberts, Navjit Sagoo, Christine Shields, Paul J. Valdes, Arne Winguth, Cornelia Winguth, and Richard D. Pancost
Clim. Past, 12, 455–481, https://doi.org/10.5194/cp-12-455-2016, https://doi.org/10.5194/cp-12-455-2016, 2016
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In this paper, we assess how well model-simulated precipitation rates compare to those indicated by geological data for the early Eocene, a warm interval 56–49 million years ago. Our results show that a number of models struggle to produce sufficient precipitation at high latitudes, which likely relates to cool simulated temperatures in these regions. However, calculating precipitation rates from plant fossils is highly uncertain, and further data are now required.
N. A. G. M. van Helmond, A. Sluijs, J. S. Sinninghe Damsté, G.-J. Reichart, S. Voigt, J. Erbacher, J. Pross, and H. Brinkhuis
Clim. Past, 11, 495–508, https://doi.org/10.5194/cp-11-495-2015, https://doi.org/10.5194/cp-11-495-2015, 2015
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Based on the chemistry and microfossils preserved in sediments deposited in a shallow sea, in the current Lower Saxony region (NW Germany), we conclude that changes in Earth’s orbit around the Sun led to enhanced rainfall and organic matter production. The additional supply of organic matter, depleting oxygen upon degradation, and freshwater, inhibiting the mixing of oxygen-rich surface waters with deeper waters, caused the development of oxygen-poor waters about 94 million years ago.
B. S. Slotnick, V. Lauretano, J. Backman, G. R. Dickens, A. Sluijs, and L. Lourens
Clim. Past, 11, 473–493, https://doi.org/10.5194/cp-11-473-2015, https://doi.org/10.5194/cp-11-473-2015, 2015
F. Peterse, C. M. Moy, and T. I. Eglinton
Biogeosciences, 12, 933–943, https://doi.org/10.5194/bg-12-933-2015, https://doi.org/10.5194/bg-12-933-2015, 2015
J. R. Buzan, K. Oleson, and M. Huber
Geosci. Model Dev., 8, 151–170, https://doi.org/10.5194/gmd-8-151-2015, https://doi.org/10.5194/gmd-8-151-2015, 2015
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We implemented the HumanIndexMod, which calculates 13 diagnostic heat stress metrics, into the Community Land Model (CLM4.5). The goal of this module is to have a common predictive framework for measuring heat stress globally. These metrics are in operational use by weather forecasters, industry, and agriculture. We show metric-dependent results of regional partitioning of extreme moisture and temperature levels in a 1901-2010 simulation.
N. Herold, J. Buzan, M. Seton, A. Goldner, J. A. M. Green, R. D. Müller, P. Markwick, and M. Huber
Geosci. Model Dev., 7, 2077–2090, https://doi.org/10.5194/gmd-7-2077-2014, https://doi.org/10.5194/gmd-7-2077-2014, 2014
A. Sluijs, L. van Roij, G. J. Harrington, S. Schouten, J. A. Sessa, L. J. LeVay, G.-J. Reichart, and C. P. Slomp
Clim. Past, 10, 1421–1439, https://doi.org/10.5194/cp-10-1421-2014, https://doi.org/10.5194/cp-10-1421-2014, 2014
L. Contreras, J. Pross, P. K. Bijl, R. B. O'Hara, J. I. Raine, A. Sluijs, and H. Brinkhuis
Clim. Past, 10, 1401–1420, https://doi.org/10.5194/cp-10-1401-2014, https://doi.org/10.5194/cp-10-1401-2014, 2014
J. S. Eldrett, D. R. Greenwood, M. Polling, H. Brinkhuis, and A. Sluijs
Clim. Past, 10, 759–769, https://doi.org/10.5194/cp-10-759-2014, https://doi.org/10.5194/cp-10-759-2014, 2014
A. Goldner, N. Herold, and M. Huber
Clim. Past, 10, 523–536, https://doi.org/10.5194/cp-10-523-2014, https://doi.org/10.5194/cp-10-523-2014, 2014
E. Gasson, D. J. Lunt, R. DeConto, A. Goldner, M. Heinemann, M. Huber, A. N. LeGrande, D. Pollard, N. Sagoo, M. Siddall, A. Winguth, and P. J. Valdes
Clim. Past, 10, 451–466, https://doi.org/10.5194/cp-10-451-2014, https://doi.org/10.5194/cp-10-451-2014, 2014
N. Preto, C. Agnini, M. Rigo, M. Sprovieri, and H. Westphal
Biogeosciences, 10, 6053–6068, https://doi.org/10.5194/bg-10-6053-2013, https://doi.org/10.5194/bg-10-6053-2013, 2013
A. Goldner, M. Huber, and R. Caballero
Clim. Past, 9, 173–189, https://doi.org/10.5194/cp-9-173-2013, https://doi.org/10.5194/cp-9-173-2013, 2013
R. L. Sriver, M. Huber, and L. Chafik
Earth Syst. Dynam., 4, 1–10, https://doi.org/10.5194/esd-4-1-2013, https://doi.org/10.5194/esd-4-1-2013, 2013
I. G. M. Wientjes, R. S. W. Van de Wal, G. J. Reichart, A. Sluijs, and J. Oerlemans
The Cryosphere, 5, 589–601, https://doi.org/10.5194/tc-5-589-2011, https://doi.org/10.5194/tc-5-589-2011, 2011
Related subject area
Subject: Feedback and Forcing | Archive: Marine Archives | Timescale: Cenozoic
Biotic response of plankton communities to Middle to Late Miocene monsoon wind and nutrient flux changes in the Oman margin upwelling zone
North Atlantic marine biogenic silica accumulation through the early to middle Paleogene: implications for ocean circulation and silicate weathering feedback
Global mean surface temperature and climate sensitivity of the early Eocene Climatic Optimum (EECO), Paleocene–Eocene Thermal Maximum (PETM), and latest Paleocene
Dynamics of sediment flux to a bathyal continental margin section through the Paleocene–Eocene Thermal Maximum
Astronomical calibration of the Ypresian timescale: implications for seafloor spreading rates and the chaotic behavior of the solar system?
Warming, euxinia and sea level rise during the Paleocene–Eocene Thermal Maximum on the Gulf Coastal Plain: implications for ocean oxygenation and nutrient cycling
Orbitally tuned timescale and astronomical forcing in the middle Eocene to early Oligocene
Cyclone trends constrain monsoon variability during late Oligocene sea level highstands (Kachchh Basin, NW India)
Productivity feedback did not terminate the Paleocene-Eocene Thermal Maximum (PETM)
High resolution cyclostratigraphy of the early Eocene – new insights into the origin of the Cenozoic cooling trend
Gerald Auer, Or M. Bialik, Mary-Elizabeth Antoulas, Noam Vogt-Vincent, and Werner E. Piller
Clim. Past, 19, 2313–2340, https://doi.org/10.5194/cp-19-2313-2023, https://doi.org/10.5194/cp-19-2313-2023, 2023
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We provided novel insights into the behaviour of a major upwelling cell between 15 and 8.5 million years ago. To study changing conditions, we apply a combination of geochemical and paleoecological parameters to characterize the nutrient availability and subsequent utilization by planktonic primary producers. These changes we then juxtapose with established records of contemporary monsoon wind intensification and changing high-latitude processes to explain shifts in the plankton community.
Jakub Witkowski, Karolina Bryłka, Steven M. Bohaty, Elżbieta Mydłowska, Donald E. Penman, and Bridget S. Wade
Clim. Past, 17, 1937–1954, https://doi.org/10.5194/cp-17-1937-2021, https://doi.org/10.5194/cp-17-1937-2021, 2021
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We reconstruct the history of biogenic opal accumulation through the early to middle Paleogene in the western North Atlantic. Biogenic opal accumulation was controlled by deepwater temperatures, atmospheric greenhouse gas levels, and continental weathering intensity. Overturning circulation in the Atlantic was established at the end of the extreme early Eocene greenhouse warmth period. We also show that the strength of the link between climate and continental weathering varies through time.
Gordon N. Inglis, Fran Bragg, Natalie J. Burls, Marlow Julius Cramwinckel, David Evans, Gavin L. Foster, Matthew Huber, Daniel J. Lunt, Nicholas Siler, Sebastian Steinig, Jessica E. Tierney, Richard Wilkinson, Eleni Anagnostou, Agatha M. de Boer, Tom Dunkley Jones, Kirsty M. Edgar, Christopher J. Hollis, David K. Hutchinson, and Richard D. Pancost
Clim. Past, 16, 1953–1968, https://doi.org/10.5194/cp-16-1953-2020, https://doi.org/10.5194/cp-16-1953-2020, 2020
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This paper presents estimates of global mean surface temperatures and climate sensitivity during the early Paleogene (∼57–48 Ma). We employ a multi-method experimental approach and show that i) global mean surface temperatures range between 27 and 32°C and that ii) estimates of
bulkequilibrium climate sensitivity (∼3 to 4.5°C) fall within the range predicted by the IPCC AR5 Report. This work improves our understanding of two key climate metrics during the early Paleogene.
Tom Dunkley Jones, Hayley R. Manners, Murray Hoggett, Sandra Kirtland Turner, Thomas Westerhold, Melanie J. Leng, Richard D. Pancost, Andy Ridgwell, Laia Alegret, Rob Duller, and Stephen T. Grimes
Clim. Past, 14, 1035–1049, https://doi.org/10.5194/cp-14-1035-2018, https://doi.org/10.5194/cp-14-1035-2018, 2018
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The Paleocene–Eocene Thermal Maximum (PETM) is a transient global warming event associated with a doubling of atmospheric carbon dioxide concentrations. Here we document a major increase in sediment accumulation rates on a subtropical continental margin during the PETM, likely due to marked changes in hydro-climates and sediment transport. These high sedimentation rates persist through the event and may play a key role in the removal of carbon from the atmosphere by the burial of organic carbon.
Thomas Westerhold, Ursula Röhl, Thomas Frederichs, Claudia Agnini, Isabella Raffi, James C. Zachos, and Roy H. Wilkens
Clim. Past, 13, 1129–1152, https://doi.org/10.5194/cp-13-1129-2017, https://doi.org/10.5194/cp-13-1129-2017, 2017
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We assembled a very accurate geological timescale from the interval 47.8 to 56.0 million years ago, also known as the Ypresian stage. We used cyclic variations in the data caused by periodic changes in Earthäs orbit around the sun as a metronome for timescale construction. Our new data compilation provides the first geological evidence for chaos in the long-term behavior of planetary orbits in the solar system, as postulated almost 30 years ago, and a possible link to plate tectonics events.
A. Sluijs, L. van Roij, G. J. Harrington, S. Schouten, J. A. Sessa, L. J. LeVay, G.-J. Reichart, and C. P. Slomp
Clim. Past, 10, 1421–1439, https://doi.org/10.5194/cp-10-1421-2014, https://doi.org/10.5194/cp-10-1421-2014, 2014
T. Westerhold, U. Röhl, H. Pälike, R. Wilkens, P. A. Wilson, and G. Acton
Clim. Past, 10, 955–973, https://doi.org/10.5194/cp-10-955-2014, https://doi.org/10.5194/cp-10-955-2014, 2014
M. Reuter, W. E. Piller, M. Harzhauser, and A. Kroh
Clim. Past, 9, 2101–2115, https://doi.org/10.5194/cp-9-2101-2013, https://doi.org/10.5194/cp-9-2101-2013, 2013
A. Torfstein, G. Winckler, and A. Tripati
Clim. Past, 6, 265–272, https://doi.org/10.5194/cp-6-265-2010, https://doi.org/10.5194/cp-6-265-2010, 2010
T. Westerhold and U. Röhl
Clim. Past, 5, 309–327, https://doi.org/10.5194/cp-5-309-2009, https://doi.org/10.5194/cp-5-309-2009, 2009
Cited articles
Agnini, C., Macrì, P., Backman, J., Brinkhuis, H., Fornaciari, E., Giusberti, L., Luciani, V., Rio, D., Sluijs, A., and Speranza, F.: An early Eocene carbon cycle perturbation at ∼52.5 Ma in the Southern Alps: Chronology and biotic response, Paleoceanography, 24, PA2209, https://doi.org/10.1029/2008PA001649, 2009.
Agnini, C., Fornaciari, E., Raffi, I., Catanzariti, R., Pälike, H., Backman, J., and Rio, D.: Biozonation and biochronology of Paleogene calcareous nannofossils from low and middle latitudes, Newslett. Stratigr., 47, 131–181, https://doi.org/10.1127/0078-0421/2014/0042, 2014.
Agterhuis, T., Ziegler, M., de Winter, N. J., and Lourens, L. J.: Warm deep-sea temperatures across Eocene Thermal Maximum 2 from clumped isotope thermometry, Commun. Earth Environ., 3, 39, https://doi.org/10.1038/s43247-022-00350-8, 2022.
Anagnostou, E., John, E. H., Babila, T. L., Sexton, P. F., Ridgwell, A., Lunt, D. J., Pearson, P. N., Chalk, T. B., Pancost, R. D., and Foster, G. L.: Proxy evidence for state-dependence of climate sensitivity in the Eocene greenhouse, Nat. Commun., 11, 4436, https://doi.org/10.1038/s41467-020-17887-x, 2020.
Annan, J. D., Hargreaves, J. C., and Mauritsen, T.: A new global surface temperature reconstruction for the Last Glacial Maximum, Clim. Past, 18, 1883–1896, https://doi.org/10.5194/cp-18-1883-2022, 2022.
Baatsen, M., Bijl, P., Von Der Heydt, A., Sluijs, A., and Dijkstra, H.: Resilient Antarctic monsoonal climate prevented ice growth during the Eocene, Clim. Past, 20, 77–90, https://doi.org/10.5194/cp-20-77-2024, 2024.
Bemis, B. E., Spero, H. J., Bijma, J., and Lea, D. W.: Reevaluation of the oxygen isotopic composition of planktonic foraminifera: Experimental results and revised paleotemperature equations, Paleoceanography, 13, 150–160, https://doi.org/10.1029/98PA00070, 1998.
Bijl, P. K., Bendle, J. A. P., Bohaty, S. M., Pross, J., Schouten, S., Tauxe, L., Stickley, C. E., McKay, R. M., Röhl, U., Olney, M., Sluijs, A., Escutia, C., Brinkhuis, H., Expedition 318 Scientists, Klaus, A., Fehr, A., Williams, T., Carr, S. A., Dunbar, R. B., Gonzàlez, J. J., Hayden, T. G., Iwai, M., Jimenez-Espejo, F. J., Katsuki, K., Kong, G. S., Nakai, M., Passchier, S., Pekar, S. F., Riesselman, C., Sakai, T., Shrivastava, P. K., Sugisaki, S., Tuo, S., van de Flierdt, T., Welsh, K., and Yamane, M.: Eocene cooling linked to early flow across the Tasmanian Gateway, P. Natl. Acad. Sci. USA, 110, 9645–9650, https://doi.org/10.1073/pnas.1220872110, 2013.
Bijl, P. K., Frieling, J., Cramwinckel, M. J., Boschman, C., Sluijs, A., and Peterse, F.: Maastrichtian–Rupelian paleoclimates in the southwest Pacific – a critical re-evaluation of biomarker paleothermometry and dinoflagellate cyst paleoecology at Ocean Drilling Program Site 1172, Clim. Past, 17, 2393–2425, https://doi.org/10.5194/cp-17-2393-2021, 2021.
Blaga, C. I., Reichart, G.-J., Heiri, O., and Sinninghe Damsté, J. S.: Tetraether membrane lipid distributions in water-column particulate matter and sediments: a study of 47 European lakes along a north–south transect, J. Paleolimnol., 41, 523–540, https://doi.org/10.1007/s10933-008-9242-2, 2009.
Caballero, R.: The dynamic range of poleward energy transport in an atmospheric general circulation model, Geophys. Res. Lett., 32, L02705, https://doi.org/10.1029/2004GL021581, 2005.
Caballero, R. and Huber, M.: State-dependent climate sensitivity in past warm climates and its implications for future climate projections, P. Natl. Acad. Sci. USA, 110, 14162–14167, https://doi.org/10.1073/pnas.1303365110, 2013.
Carmichael, M. J., Inglis, G. N., Badger, M. P. S., Naafs, B. D. A., Behrooz, L., Remmelzwaal, S., Monteiro, F. M., Rohrssen, M., Farnsworth, A., Buss, H. L., Dickson, A. J., Valdes, P. J., Lunt, D. J., and Pancost, R. D.: Hydrological and associated biogeochemical consequences of rapid global warming during the Paleocene-Eocene Thermal Maximum, Global Planet. Change, 157, 114–138, https://doi.org/10.1016/j.gloplacha.2017.07.014, 2017.
Cramer, B. S., Wright, J. D., Kent, D. V., and Aubry, M.-P.: Orbital climate forcing of D13C excursions in the late Paleocene – early Eocene (chrons C24n–C25n), Paleoceanography, 18, 1097, https://doi.org/10.1029/2003PA000909, 2003.
Cramwinckel, M. J., Huber, M., Kocken, I. J., Agnini, C., Bijl, P. K., Bohaty, S. M., Frieling, J., Goldner, A., Hilgen, F. J., Kip, E. L., Peterse, F., van der Ploeg, R., Röhl, U., Schouten, S., and Sluijs, A.: Synchronous tropical and polar temperature evolution in the Eocene, Nature, 559, 382–386, https://doi.org/10.1038/s41586-018-0272-2, 2018.
Deconto, R. M., Brady, E. C., Bergengren, J., and Hay, W. W.: Late Cretaceous climate, vegetation, and ocean interactions, in: Warm Climates in Earth History, edited by: Huber, B. T., Macleod, K. G., and Wing, S. L., Cambridge University Press, 275–296, https://doi.org/10.1017/CBO9780511564512.010, 1999.
DeConto, R. M., Galeotti, S., Pagani, M., Tracy, D., Schaefer, K., Zhang, T., Pollard, D., and Beerling, D. J.: Past extreme warming events linked to massive carbon release from thawing permafrost, Nature, 484, 87–91, https://doi.org/10.1038/nature10929, 2012.
Dickens, G. R.: Carbon addition and removal during the Late Palaeocene Thermal Maximum: basic theory with a preliminary treatment of the isotope record at ODP Site 1051, Blake Nose, Geol. Soc. Lond. Spec. Publ., 183, 293–305, https://doi.org/10.1144/GSL.SP.2001.183.01.14, 2001a.
Dickens, G. R.: The potential volume of oceanic methane hydrates with variable external conditions, Org. Geochem., 32, 1179–1193, https://doi.org/10.1016/S0146-6380(01)00086-9, 2001b.
Dickens, G. R., Castillo, M. M., and Walker, J. C. G.: A blast of gas in the latest Paleocene: Simulating first-order effects of massive dissociation of oceanic methane hydrate, Geology, 25, 259, https://doi.org/10.1130/0091-7613(1997)025<0259:ABOGIT>2.3.CO;2, 1997.
Dunkley Jones, T., Lunt, D. J., Schmidt, D. N., Ridgwell, A., Sluijs, A., Valdes, P. J., and Maslin, M.: Climate model and proxy data constraints on ocean warming across the Paleocene–Eocene Thermal Maximum, Earth-Sci. Rev., 125, 123–145, https://doi.org/10.1016/j.earscirev.2013.07.004, 2013.
England, M. R. and Feldl, N.: Robust Polar Amplification in Ice-Free Climates Relies on Ocean Heat Transport and Cloud Radiative Effects, J. Climate, 37, 2179–2197, https://doi.org/10.1175/JCLI-D-23-0151.1, 2024.
England, M. R., Eisenman, I., Lutsko, N. J., and Wagner, T. J. W.: The Recent Emergence of Arctic Amplification, Geophys. Res. Lett., 48, e2021GL094086, https://doi.org/10.1029/2021GL094086, 2021.
Evans, D., Sagoo, N., Renema, W., Cotton, L. J., Müller, W., Todd, J. A., Saraswati, P. K., Stassen, P., Ziegler, M., Pearson, P. N., Valdes, P. J., and Affek, H. P.: Eocene greenhouse climate revealed by coupled clumped isotope-Mg/Ca thermometry, P. Natl. Acad. Sci. USA, 115, 1174–1179, https://doi.org/10.1073/pnas.1714744115, 2018.
Frieling, J. and Sluijs, A.: Towards quantitative environmental reconstructions from ancient non-analogue microfossil assemblages: Ecological preferences of Paleocene–Eocene dinoflagellates, Earth-Sci. Rev., 185, 956–973, https://doi.org/10.1016/j.earscirev.2018.08.014, 2018.
Frieling, J., Gebhardt, H., Huber, M., Adekeye, O. A., Akande, S. O., Reichart, G.-J., Middelburg, J. J., Schouten, S., and Sluijs, A.: Extreme warmth and heat-stressed plankton in the tropics during the Paleocene-Eocene Thermal Maximum, Sci. Adv., 3, e1600891, https://doi.org/10.1126/sciadv.1600891, 2017.
Frieling, J., Reichart, G.-J., Middelburg, J. J., Röhl, U., Westerhold, T., Bohaty, S. M., and Sluijs, A.: Tropical Atlantic climate and ecosystem regime shifts during the Paleocene–Eocene Thermal Maximum, Clim. Past, 14, 39–55, https://doi.org/10.5194/cp-14-39-2018, 2018.
Frieling, J., Peterse, F., Lunt, D. J., Bohaty, S. M., Sinninghe Damsté, J. S., Reichart, G.-J., and Sluijs, A.: Widespread Warming Before and Elevated Barium Burial During the Paleocene-Eocene Thermal Maximum: Evidence for Methane Hydrate Release?, Paleoceanogr. Paleoclimatol., 34, 546–566, https://doi.org/10.1029/2018PA003425, 2019.
Gaskell, D. E., Huber, M., O'Brien, C. L., Inglis, G. N., Acosta, R. P., Poulsen, C. J., and Hull, P. M.: The latitudinal temperature gradient and its climate dependence as inferred from foraminiferal δ18O over the past 95 million years, P. Natl. Acad. Sci. USA, 119, e2111332119, https://doi.org/10.1073/pnas.2111332119, 2022.
Gibbs, S. J., Bown, P. R., Murphy, B. H., Sluijs, A., Edgar, K. M., Pälike, H., Bolton, C. T., and Zachos, J. C.: Scaled biotic disruption during early Eocene global warming events, Biogeosciences, 9, 4679–4688, https://doi.org/10.5194/bg-9-4679-2012, 2012.
Harper, D. T., Zeebe, R., Hönisch, B., Schrader, C. D., Lourens, L. J., and Zachos, J. C.: Subtropical sea-surface warming and increased salinity during Eocene Thermal Maximum 2, Geology, 46, 187–190, https://doi.org/10.1130/G39658.1, 2018.
Held, I. M. and Soden, B. J.: Robust Responses of the Hydrological Cycle to Global Warming, J. Climate, 19, 5686–5699, https://doi.org/10.1175/JCLI3990.1, 2006.
Herbert, T. D., Peterson, L. C., Lawrence, K. T., and Liu, Z.: Tropical Ocean Temperatures Over the Past 3.5 Million Years, Science, 328, 1530–1534, https://doi.org/10.1126/science.1185435, 2010.
Hernández-Sánchez, M. T., Woodward, E. M. S., Taylor, K. W. R., Henderson, G. M., and Pancost, R. D.: Variations in GDGT distributions through the water column in the South East Atlantic Ocean, Geochim. Cosmochim. Ac., 132, 337–348, https://doi.org/10.1016/j.gca.2014.02.009, 2014.
Ho, S. L. and Laepple, T.: Flat meridional temperature gradient in the early Eocene in the subsurface rather than surface ocean, Nat. Geosci., 9, 606–610, https://doi.org/10.1038/ngeo2763, 2016.
Ho, S. L., Mollenhauer, G., Lamy, F., Martínez-Garcia, A., Mohtadi, M., Gersonde, R., Hebbeln, D., Nunez-Ricardo, S., Rosell-Melé, A., and Tiedemann, R.: Sea surface temperature variability in the Pacific sector of the Southern Ocean over the past 700 kyr, Paleoceanography, 27, PA4202, https://doi.org/10.1029/2012PA002317, 2012.
Hollis, C. J., Taylor, K. W. R., Handley, L., Pancost, R. D., Huber, M., Creech, J. B., Hines, B. R., Crouch, E. M., Morgans, H. E. G., Crampton, J. S., Gibbs, S., Pearson, P. N., and Zachos, J. C.: Early Paleogene temperature history of the Southwest Pacific Ocean: Reconciling proxies and models, Earth Planet. Sc. Lett., 349–350, 53–66, https://doi.org/10.1016/j.epsl.2012.06.024, 2012.
Hollis, C. J., Dunkley Jones, T., Anagnostou, E., Bijl, P. K., Cramwinckel, M. J., Cui, Y., Dickens, G. R., Edgar, K. M., Eley, Y., Evans, D., Foster, G. L., Frieling, J., Inglis, G. N., Kennedy, E. M., Kozdon, R., Lauretano, V., Lear, C. H., Littler, K., Lourens, L., Meckler, A. N., Naafs, B. D. A., Pälike, H., Pancost, R. D., Pearson, P. N., Röhl, U., Royer, D. L., Salzmann, U., Schubert, B. A., Seebeck, H., Sluijs, A., Speijer, R. P., Stassen, P., Tierney, J., Tripati, A., Wade, B., Westerhold, T., Witkowski, C., Zachos, J. C., Zhang, Y. G., Huber, M., and Lunt, D. J.: The DeepMIP contribution to PMIP4: methodologies for selection, compilation and analysis of latest Paleocene and early Eocene climate proxy data, incorporating version 0.1 of the DeepMIP database, Geosci. Model Dev., 12, 3149–3206, https://doi.org/10.5194/gmd-12-3149-2019, 2019.
Hopmans, E. C., Weijers, J. W. H., Schefuß, E., Herfort, L., Sinninghe Damsté, J. S., and Schouten, S.: A novel proxy for terrestrial organic matter in sediments based on branched and isoprenoid tetraether lipids, Earth Planet. Sc. Lett., 224, 107–116, https://doi.org/10.1016/j.epsl.2004.05.012, 2004.
Hopmans, E. C., Schouten, S., and Sinninghe Damsté, J. S.: The effect of improved chromatography on GDGT-based palaeoproxies, Org. Geochem., 93, 1–6, https://doi.org/10.1016/j.orggeochem.2015.12.006, 2016.
Huber, M. and Nof, D.: The ocean circulation in the southern hemisphere and its climatic impacts in the Eocene, Palaeogeogr. Palaeoclim. Palaeoecol., 231, 9–28, https://doi.org/10.1016/j.palaeo.2005.07.037, 2006.
Huck, C. E., van de Flierdt, T., Bohaty, S. M., and Hammond, S. J.: Antarctic climate, Southern Ocean circulation patterns, and deep water formation during the Eocene: Eocene Southern Ocean Circulation, Paleoceanography, 32, 674–691, https://doi.org/10.1002/2017PA003135, 2017.
Hurley, S. J., Lipp, J. S., Close, H. G., Hinrichs, K.-U., and Pearson, A.: Distribution and export of isoprenoid tetraether lipids in suspended particulate matter from the water column of the Western Atlantic Ocean, Org. Geochem., 116, 90–102, https://doi.org/10.1016/j.orggeochem.2017.11.010, 2018.
Hut, G.: Consultants' group meeting on stable isotope reference samples for geochemical and hydrological investigations, International Atomic Energy Agency, Vienna, https://inis.iaea.org/search/search.aspx?orig_q=RN:18075746 (last access: 10 June 2024), 1987.
Inglis, G. N., Bragg, F., Burls, N. J., Cramwinckel, M. J., Evans, D., Foster, G. L., Huber, M., Lunt, D. J., Siler, N., Steinig, S., Tierney, J. E., Wilkinson, R., Anagnostou, E., de Boer, A. M., Dunkley Jones, T., Edgar, K. M., Hollis, C. J., Hutchinson, D. K., and Pancost, R. D.: Global mean surface temperature and climate sensitivity of the early Eocene Climatic Optimum (EECO), Paleocene–Eocene Thermal Maximum (PETM), and latest Paleocene, Clim. Past, 16, 1953–1968, https://doi.org/10.5194/cp-16-1953-2020, 2020.
Karner, M. B., DeLong, E. F., and Karl, D. M.: Archaeal dominance in the mesopelagic zone of the Pacific Ocean, Nature, 409, 507–510, 2001.
Kennett, J. P. and Stott, L. D.: Abrupt deep-sea warming, palaeoceanographic changes and benthic extinctions at the end of the Palaeocene, Nature, 353, 225–229, https://doi.org/10.1038/353225a0, 1991.
Kim, J.-H., van der Meer, J., Schouten, S., Helmke, P., Willmott, V., Sangiorgi, F., Koç, N., Hopmans, E. C., and Damsté, J. S. S.: New indices and calibrations derived from the distribution of crenarchaeal isoprenoid tetraether lipids: Implications for past sea surface temperature reconstructions, Geochim. Cosmochim. Ac., 74, 4639–4654, https://doi.org/10.1016/j.gca.2010.05.027, 2010.
Kim, J.-H., Romero, O. E., Lohmann, G., Donner, B., Laepple, T., Haam, E., and Sinninghe Damsté, J. S.: Pronounced subsurface cooling of North Atlantic waters off Northwest Africa during Dansgaard–Oeschger interstadials, Earth Planet. Sc. Lett., 339–340, 95–102, https://doi.org/10.1016/j.epsl.2012.05.018, 2012.
Kim, S.-T. and O'Neil, J. R.: Equilibrium and nonequilibrium oxygen isotope effects in synthetic carbonates, Geochim. Cosmochim. Ac., 61, 3461–3475, https://doi.org/10.1016/S0016-7037(97)00169-5, 1997.
Komar, N., Zeebe, R. E., and Dickens, G. R.: Understanding long-term carbon cycle trends: The late Paleocene through the early Eocene, Paleoceanography, 28, 650–662, https://doi.org/10.1002/palo.20060, 2013.
Kurtz, A. C., Kump, L. R., Arthur, M. A., Zachos, J. C., and Paytan, A.: Early Cenozoic decoupling of the global carbon and sulfur cycles, Paleoceanography, 18, 1090, https://doi.org/10.1029/2003PA000908, 2003.
Laskar, J., Fienga, A., Gastineau, M., and Manche, H.: La2010: a new orbital solution for the long-term motion of the Earth, Astron. Astrophys., 532, A89, https://doi.org/10.1051/0004-6361/201116836, 2011.
Lauretano, V., Littler, K., Polling, M., Zachos, J. C., and Lourens, L. J.: Frequency, magnitude and character of hyperthermal events at the onset of the Early Eocene Climatic Optimum, Clim. Past, 11, 1313–1324, https://doi.org/10.5194/cp-11-1313-2015, 2015.
Lauretano, V., Zachos, J. C., and Lourens, L. J.: Orbitally Paced Carbon and Deep-Sea Temperature Changes at the Peak of the Early Eocene Climatic Optimum, Paleoceanogr. Paleoclimatol., 33, 1050–1065, https://doi.org/10.1029/2018PA003422, 2018.
Lawrence, K. T., Herbert, T. D., Brown, C. M., Raymo, M. E., and Haywood, A. M.: High-amplitude variations in North Atlantic sea surface temperature during the early Pliocene warm period, Paleoceanography, 24, PA2218, https://doi.org/10.1029/2008PA001669, 2009.
Leon-Rodriguez, L. and Dickens, G. R.: Constraints on ocean acidification associated with rapid and massive carbon injections: The early Paleogene record at ocean drilling program site 1215, equatorial Pacific Ocean, Palaeogeogr. Palaeoecol., 298, 409–420, https://doi.org/10.1016/j.palaeo.2010.10.029, 2010.
Littler, K., Röhl, U., Westerhold, T., and Zachos, J. C.: A high-resolution benthic stable-isotope record for the South Atlantic: Implications for orbital-scale changes in Late Paleocene–Early Eocene climate and carbon cycling, Earth Planet. Sc. Lett., 401, 18–30, https://doi.org/10.1016/j.epsl.2014.05.054, 2014.
Liu, X., Huber, M., Foster, G. L., Dessler, A., and Zhang, Y. G.: Persistent high latitude amplification of the Pacific Ocean over the past 10 million years, Nat. Commun., 13, 7310, https://doi.org/10.1038/s41467-022-35011-z, 2022.
Liu, Z., Pagani, M., Zinniker, D., DeConto, R., Huber, M., Brinkhuis, H., Shah, S. R., Leckie, R. M., and Pearson, A.: Global Cooling During the Eocene-Oligocene Climate Transition, Science, 323, 1187–1190, https://doi.org/10.1126/science.1166368, 2009.
Locarnini, M., Mishonov, A., Baranova, O., Boyer, T., Zweng, M., Garcia, H., Reagan, J., Seidov, D., Weathers, K., Paver, C., and Smolyar, I.: World Ocean Atlas 2018, Volume 1: Temperature, edited by: Mishonov, A., NOAA Atlas NESDIS 81, 52 pp., https://archimer.ifremer.fr/doc/00651/76338/ (last access: December 2021), 2018.
Locarnini, R. A., Mishonov, A. V., Antonov, A. V., Boyer, T. P., Garcia, H. E., Baranova, O. K., Zweng, M. M., and Johnson, D. R.: World Ocean Atlas 2009, Volume 1: Temperature, edited by: Levitus, S., NOAA Atlas NESDIS 68, 184 pp., https://www.ncei.noaa.gov/sites/default/files/2020-04/woa09_vol1_text.pdf (last access: 10 June 2024), 2010.
Lourens, L. J., Sluijs, A., Kroon, D., Zachos, J. C., Thomas, E., Röhl, U., Bowles, J., and Raffi, I.: Astronomical pacing of late Palaeocene to early Eocene global warming events, Nature, 435, 1083–1087, https://doi.org/10.1038/nature03814, 2005.
Lunt, D. J., Bragg, F., Chan, W.-L., Hutchinson, D. K., Ladant, J.-B., Morozova, P., Niezgodzki, I., Steinig, S., Zhang, Z., Zhu, J., Abe-Ouchi, A., Anagnostou, E., de Boer, A. M., Coxall, H. K., Donnadieu, Y., Foster, G., Inglis, G. N., Knorr, G., Langebroek, P. M., Lear, C. H., Lohmann, G., Poulsen, C. J., Sepulchre, P., Tierney, J. E., Valdes, P. J., Volodin, E. M., Jones, T. D., Hollis, C. J., Huber, M., and Otto-Bliesner, L.: DeepMIP: Model intercomparison of early Eocene climatic optimum (EECO) large-scale climate features and comparison with proxy data, Clim. Past, 17, 203–227, https://doi.org/10.5194/cp-17-203-2021, 2021.
Martínez-Garcia, A., Rosell-Melé, A., McClymont, E. L., Gersonde, R., and Haug, G. H.: Subpolar Link to the Emergence of the Modern Equatorial Pacific Cold Tongue, Science, 328, 1550–1553, https://doi.org/10.1126/science.1184480, 2010.
Mascle, J., Lohmann, G. P., Clift, P. D., and Shipboard Scientific Party, Proc. ODP Init. Repts., 159, 65–150, https://doi.org/10.2973/odp.proc.ir.159.1996, 1996.
Massana, R., DeLong, E. F., and Pedrós-Alió, C.: A Few Cosmopolitan Phylotypes Dominate Planktonic Archaeal Assemblages in Widely Different Oceanic Provinces, Appl. Environ. Microbiol., 66, 1777–1787, https://doi.org/10.1128/AEM.66.5.1777-1787.2000, 2000.
Masson-Delmotte, V., Schulz, M., Abe-Ouchi, A., Beer, J., Ganopolski, A., Gonzalez Rouco, J. F., Jansen, E., Lambeck, K., Luterbacher, J., Naish, T., Osborn, T., Otto-Bliesner, B., Quinn, T., Ramesh, R., Rojas, M., Shao, X., and Timmermann, A.: Information from paleoclimate archives, in: Climate change 2013: the physical science basis, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M. M. B., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, 383–464, https://doi.org/10.1017/CBO9781107415324.013, 2013.
Matthews, K. J., Maloney, K. T., Zahirovic, S., Williams, S. E., Seton, M., and Müller, R. D.: Global plate boundary evolution and kinematics since the late Paleozoic, Global Planet. Change, 146, 226–250, https://doi.org/10.1016/j.gloplacha.2016.10.002, 2016.
McInerney, F. A. and Wing, S. L.: The Paleocene-Eocene Thermal Maximum: A Perturbation of Carbon Cycle, Climate, and Biosphere with Implications for the Future, Annu. Rev. Earth Planet. Sc., 39, 489–516, https://doi.org/10.1146/annurev-earth-040610-133431, 2011.
Meckler, A. N., Sexton, P. F., Piasecki, A. M., Leutert, T. J., Marquardt, J., Ziegler, M., Agterhuis, T., Lourens, L. J., Rae, J. W. B., Barnet, J., Tripati, A., and Bernasconi, S. M.: Cenozoic evolution of deep ocean temperature from clumped isotope thermometry, Science, 377, 86–90, https://doi.org/10.1126/science.abk0604, 2022.
Merbt, S. N., Stahl, D. A., Casamayor, E. O., Martí, E., Nicol, G. W., and Prosser, J. I.: Differential photoinhibition of bacterial and archaeal ammonia oxidation, FEMS Microbiol. Lett., 327, 41–46, https://doi.org/10.1111/j.1574-6968.2011.02457.x, 2012.
Müller, R. D., Cannon, J., Qin, X., Watson, R. J., Gurnis, M., Williams, S., Pfaffelmoser, T., Seton, M., Russell, S. H. J., and Zahirovic, S.: GPlates: Building a Virtual Earth Through Deep Time, Geochem. Geophy. Geosy., 19, 2243–2261, https://doi.org/10.1029/2018GC007584, 2018.
O'Brien, C. L., Robinson, S. A., Pancost, R. D., Sinninghe Damsté, J. S., Schouten, S., Lunt, D. J., Alsenz, H., Bornemann, A., Bottini, C., Brassell, S. C., Farnsworth, A., Forster, A., Huber, B. T., Inglis, G. N., Jenkyns, H. C., Linnert, C., Littler, K., Markwick, P., McAnena, A., Mutterlose, J., Naafs, B. D. A., Püttmann, W., Sluijs, A., van Helmond, N. A. G. M., Vellekoop, J., Wagner, T., and Wrobel, N. E.: Cretaceous sea-surface temperature evolution: Constraints from TEX86 and planktonic foraminiferal oxygen isotopes, Earth-Sci. Rev., 172, 224–247, https://doi.org/10.1016/j.earscirev.2017.07.012, 2017.
Osman, M. B., Tierney, J. E., Zhu, J., Tardif, R., Hakim, G. J., King, J., and Poulsen, C. J.: Globally resolved surface temperatures since the Last Glacial Maximum, Nature, 599, 239–244, https://doi.org/10.1038/s41586-021-03984-4, 2021.
PALAEOSENS Project Members: Making sense of palaeoclimate sensitivity, Nature, 491, 683–691, https://doi.org/10.1038/nature11574, 2012.
Pithan, F. and Mauritsen, T.: Arctic amplification dominated by temperature feedbacks in contemporary climate models, Nat. Geosci., 7, 181–184, https://doi.org/10.1038/ngeo2071, 2014.
Pross, J., Contreras, L., Bijl, P. K., Greenwood, D. R., Bohaty, S. M., Schouten, S., Bendle, J. A., Röhl, U., Tauxe, L., Raine, J. I., Huck, C. E., van de Flierdt, T., Jamieson, S. S. R., Stickley, C. E., van de Schootbrugge, B., Escutia, C., Brinkhuis, H., and Integraded Ocean Drilling Program Expedition 318 Scientists: Persistent near-tropical warmth on the Antarctic continent during the early Eocene epoch, Nature, 488, 73–77, https://doi.org/10.1038/nature11300, 2012.
Rattanasriampaipong, R., Zhang, Y. G., Pearson, A., Hedlund, B. P., and Zhang, S.: Archaeal lipids trace ecology and evolution of marine ammonia-oxidizing archaea, P. Natl. Acad. Sci. USA, 119, e2123193119, https://doi.org/10.1073/pnas.2123193119, 2022.
Sagoo, N., Valdes, P., Flecker, R., and Gregoire, L. J.: The Early Eocene equable climate problem: can perturbations of climate model parameters identify possible solutions?, Philos. T. Roy. Soc. A, 371, 20130123, https://doi.org/10.1098/rsta.2013.0123, 2013.
Schouten, S., Hopmans, E. C., Schefuß, E., and Sinninghe Damsté, J. S.: Distributional variations in marine crenarchaeotal membrane lipids: a new tool for reconstructing ancient sea water temperatures?, Earth Planet. Sc. Lett., 204, 265–274, https://doi.org/10.1016/S0012-821X(02)00979-2, 2002.
Setty, S., Cramwinckel, M. J., Van Nes, E. H., Van De Leemput, I. A., Dijkstra, H. A., Lourens, L. J., Scheffer, M., and Sluijs, A.: Loss of Earth system resilience during early Eocene transient global warming events, Sci. Adv., 9, eade5466, https://doi.org/10.1126/sciadv.ade5466, 2023.
Sinninghe Damsté, J. S., Rijpstra, W. I. C., Hopmans, E. C., Prahl, F. G., Wakeham, S. G., and Schouten, S.: Distribution of Membrane Lipids of Planktonic Crenarchaeota in the Arabian Sea, Appl. Environ. Microbiol., 68, 2997–3002, https://doi.org/10.1128/AEM.68.6.2997-3002.2002, 2002.
Slotnick, B. S., Dickens, G. R., Nicolo, M. J., Hollis, C. J., Crampton, J. S., Zachos, J. C., and Sluijs, A.: Large-Amplitude Variations in Carbon Cycling and Terrestrial Weathering during the Latest Paleocene and Earliest Eocene: The Record at Mead Stream, New Zealand, J. Geol., 120, 487–505, https://doi.org/10.1086/666743, 2012.
Sluijs, A., Pross, J., and Brinkhuis, H.: From greenhouse to icehouse; organic-walled dinoflagellate cysts as paleoenvironmental indicators in the Paleogene, Earth-Sci. Rev., 68, 281–315, https://doi.org/10.1016/j.earscirev.2004.06.001, 2005.
Sluijs, A., Schouten, S., Donders, T. H., Schoon, P. L., Röhl, U., Reichart, G.-J., Sangiorgi, F., Kim, J.-H., Sinninghe Damsté, J. S., and Brinkhuis, H.: Warm and wet conditions in the Arctic region during Eocene Thermal Maximum 2, Nat. Geosci., 2, 777–780, https://doi.org/10.1038/ngeo668, 2009.
Sluijs, A., Frieling, J., Inglis, G. N., Nierop, K. G. J., Peterse, F., Sangiorgi, F., and Schouten, S.: Late Paleocene–early Eocene Arctic Ocean sea surface temperatures: reassessing biomarker paleothermometry at Lomonosov Ridge, Clim. Past, 16, 2381–2400, https://doi.org/10.5194/cp-16-2381-2020, 2020.
Sluijs, A., Fokkema, C. D., Agterhuis, T., Gerritsma, D., de Goeij, M., Liu, X., de Regt, P., Rice, A., Vennema, L., Agnini, C., Bijl, P. K., Frieling, J., Huber, M., Peterse, F., Wubben, E., Spiering, B., Veenstra, T., Bos, R., Wang, Z., van Dijk, J., Raffi, I., Witkowski, J., Hilgen, F., Peterse, F., and Sangiorgi, F.: Ocean Drilling Program Site 959 Datasets (1.0.0), Zenodo [data set], https://doi.org/10.5281/zenodo.8309643, 2023.
Stap, L., Sluijs, A., Thomas, E., and Lourens, L.: Patterns and magnitude of deep sea carbonate dissolution during Eocene Thermal Maximum 2 and H2, Walvis Ridge, southeastern Atlantic Ocean, Paleoceanography, 24, PA1211, https://doi.org/10.1029/2008PA001655, 2009.
Stap, L., Lourens, L. J., Thomas, E., Sluijs, A., Bohaty, S., and Zachos, J. C.: High-resolution deep-sea carbon and oxygen isotope records of Eocene Thermal Maximum 2 and H2, Geology, 38, 607–610, https://doi.org/10.1130/G30777.1, 2010.
Stockmarr, J.: Tablets with spores used in absolute pollen analysis, Pollen Spores, 13, 615–621, 1972.
Stuecker, M. F., Bitz, C. M., Armour, K. C., Proistosescu, C., Kang, S. M., Xie, S.-P., Kim, D., McGregor, S., Zhang, W., Zhao, S., Cai, W., Dong, Y., and Jin, F.-F.: Polar amplification dominated by local forcing and feedbacks, Nat. Clim. Change, 8, 1076–1081, https://doi.org/10.1038/s41558-018-0339-y, 2018.
Taylor, K. W. R., Huber, M., Hollis, C. J., Hernandez-Sanchez, M. T., and Pancost, R. D.: Re-evaluating modern and Palaeogene GDGT distributions: Implications for SST reconstructions, Global Planet. Change, 108, 158–174, https://doi.org/10.1016/j.gloplacha.2013.06.011, 2013.
Taylor, P. C., Cai, M., Hu, A., Meehl, J., Washington, W., and Zhang, G. J.: A Decomposition of Feedback Contributions to Polar Warming Amplification, J. Climate, 26, 7023–7043, https://doi.org/10.1175/JCLI-D-12-00696.1, 2013.
Thomas, E. and Zachos, J. C.: Was the late Paleocene thermal maximum a unique event?, GFF, 122, 169–170, https://doi.org/10.1080/11035890001221169, 2000.
Thomas, E., Boscolo-Galazzo, F., Balestra, B., Monechi, S., Donner, B., and Röhl, U.: Early Eocene Thermal Maximum 3: Biotic Response at Walvis Ridge (SE Atlantic Ocean), Paleoceanogr. Paleoclimatol., 33, 862–883, https://doi.org/10.1029/2018PA003375, 2018.
Tierney, J. E. and Tingley, M. P.: A Bayesian, spatially-varying calibration model for the TEX86 proxy, Geochim. Cosmochim. Ac., 127, 83–106, https://doi.org/10.1016/j.gca.2013.11.026, 2014.
Tierney, J. E. and Tingley, M. P.: A TEX86 surface sediment database and extended Bayesian calibration, Sci, Data, 2, 150029, https://doi.org/10.1038/sdata.2015.29, 2015.
Tierney, J. E., Sinninghe Damsté, J. S., Pancost, R. D., Sluijs, A., and Zachos, J. C.: Eocene temperature gradients, Nat. Geosci., 10, 538–539, https://doi.org/10.1038/ngeo2997, 2017.
Tierney, J. E., Zhu, J., Li, M., Ridgwell, A., Hakim, G. J., Poulsen, C. J., Whiteford, R. D. M., Rae, J. W. B., and Kump, L. R.: Spatial patterns of climate change across the Paleocene–Eocene Thermal Maximum, P. Natl. Acad. Sci. USA, 119, e2205326119, https://doi.org/10.1073/pnas.2205326119, 2022.
Torsvik, T. H., Van der Voo, R., Preeden, U., Mac Niocaill, C., Steinberger, B., Doubrovine, P. V., van Hinsbergen, D. J. J., Domeier, M., Gaina, C., Tohver, E., Meert, J. G., McCausland, P. J. A., and Cocks, L. R. M.: Phanerozoic polar wander, palaeogeography and dynamics, Earth-Sci. Rev., 114, 325–368, https://doi.org/10.1016/j.earscirev.2012.06.007, 2012.
van der Ploeg, R., Selby, D., Cramwinckel, M. J., Li, Y., Bohaty, S. M., Middelburg, J. J., and Sluijs, A.: Middle Eocene greenhouse warming facilitated by diminished weathering feedback, Nat. Commun., 9, 2877, https://doi.org/10.1038/s41467-018-05104-9, 2018.
van der Weijst, C. M. H., Winkelhorst, J., de Nooijer, W., von der Heydt, A., Reichart, G.-J., Sangiorgi, F., and Sluijs, A.: Pliocene evolution of the tropical Atlantic thermocline depth, Clim. Past, 18, 961–973, https://doi.org/10.5194/cp-18-961-2022, 2022.
Vavrus, S.: The Impact of Cloud Feedbacks on Arctic Climate under Greenhouse Forcing, J. Climate, 17, 603–615, https://doi.org/10.1175/1520-0442(2004)017<0603:TIOCFO>2.0.CO;2, 2004.
Vervoort, P., Kirtland Turner, S., Rochholz, F., and Ridgwell, A.: Earth System Model Analysis of How Astronomical Forcing Is Imprinted Onto the Marine Geological Record: The Role of the Inorganic (Carbonate) Carbon Cycle and Feedbacks, Paleoceanogr. Paleoclimatol., 39, e2023PA004826, https://doi.org/10.1029/2023PA004826, 2024.
Villanueva, L., Schouten, S., and Sinninghe Damsté, J. S.: Depth-related distribution of a key gene of the tetraether lipid biosynthetic pathway in marine Thaumarchaeota: Distribution of a thaumarchaeotal lipid enzyme, Environ. Microbiol., 17, 3527–3539, https://doi.org/10.1111/1462-2920.12508, 2015.
Wagner, T.: Late Cretaceous to early Quaternary organic sedimentation in the eastern Equatorial Atlantic, Palaeogeogr. Palaeocl., 179, 113–147, https://doi.org/10.1016/S0031-0182(01)00415-1, 2002.
Weijers, J. W. H., Lim, K. L. H., Aquilina, A., Sinninghe Damsté, J. S., and Pancost, R. D.: Biogeochemical controls on glycerol dialkyl glycerol tetraether lipid distributions in sediments characterized by diffusive methane flux, Geochem. Geophy. Geosys., 12, Q10010, https://doi.org/10.1029/2011GC003724, 2011.
Westerhold, T., Röhl, U., Frederichs, T., Agnini, C., Raffi, I., Zachos, J. C., and Wilkens, R. H.: Astronomical calibration of the Ypresian timescale: implications for seafloor spreading rates and the chaotic behavior of the solar system?, Clim. Past, 13, 1129–1152, https://doi.org/10.5194/cp-13-1129-2017, 2017.
Westerhold, T., Röhl, U., Donner, B., and Zachos, J. C.: Global Extent of Early Eocene Hyperthermal Events: A New Pacific Benthic Foraminiferal Isotope Record From Shatsky Rise (ODP Site 1209), Paleoceanogr. Paleoclimatol., 33, 626–642, https://doi.org/10.1029/2017PA003306, 2018.
Westerhold, T., Marwan, N., Drury, A. J., Liebrand, D., Agnini, C., Anagnostou, E., Barnet, J. S. K., Bohaty, S. M., De Vleeschouwer, D., Florindo, F., Frederichs, T., Hodell, D. A., Holbourn, A. E., Kroon, D., Lauretano, V., Littler, K., Lourens, L. J., Lyle, M., Pälike, H., Röhl, U., Tian, J., Wilkens, R. H., Wilson, P. A., and Zachos, J. C.: An astronomically dated record of Earth's climate and its predictability over the last 66 million years, Science, 369, 1383–1387, https://doi.org/10.1126/science.aba6853, 2020.
Willard, D. A., Donders, T. H., Reichgelt, T., Greenwood, D. R., Sangiorgi, F., Peterse, F., Nierop, K. G. J., Frieling, J., Schouten, S., and Sluijs, A.: Arctic vegetation, temperature, and hydrology during Early Eocene transient global warming events, Global Planet. Change, 178, 139–152, https://doi.org/10.1016/j.gloplacha.2019.04.012, 2019.
Zachos, J., Pagani, M., Sloan, L., Thomas, E., and Billups, K.: Trends, Rhythms, and Aberrations in Global Climate 65 Ma to Present, Science, 292, 686–693, https://doi.org/10.1126/science.1059412, 2001.
Zachos, J. C., Röhl, U., Schellenberg, S. A., Sluijs, A., Hodell, D. A., Kelly, D. C., Thomas, E., Nicolo, M., Raffi, I., Lourens, L. J., McCarren, H., and Kroon, D.: Rapid Acidification of the Ocean During the Paleocene-Eocene Thermal Maximum, Science, 308, 1611–1615, https://doi.org/10.1126/science.1109004, 2005.
Zachos, J. C., McCarren, H., Murphy, B., Röhl, U., and Westerhold, T.: Tempo and scale of late Paleocene and early Eocene carbon isotope cycles: Implications for the origin of hyperthermals, Earth Planet. Sc. Lett., 299, 242–249, https://doi.org/10.1016/j.epsl.2010.09.004, 2010.
Zakem, E. J., Al-Haj, A., Church, M. J., van Dijken, G. L., Dutkiewicz, S., Foster, S. Q., Fulweiler, R. W., Mills, M. M., and Follows, M. J.: Ecological control of nitrite in the upper ocean, Nat. Commun., 9, 1206, https://doi.org/10.1038/s41467-018-03553-w, 2018.
Zeebe, R. E., Westerhold, T., Littler, K., and Zachos, J. C.: Orbital forcing of the Paleocene and Eocene carbon cycle, Paleoceanography, 32, 440–465, https://doi.org/10.1002/2016PA003054, 2017.
Zelinka, M. D., Klein, S. A., Qin, Y., and Myers, T. A.: Evaluating Climate Models' Cloud Feedbacks Against Expert Judgment, J. Geophys. Res.-Atmos., 127, e2021JD035198, https://doi.org/10.1029/2021JD035198, 2022.
Zhang, Y., Huck, T., Lique, C., Donnadieu, Y., Ladant, J.-B., Rabineau, M., and Aslanian, D.: Early Eocene vigorous ocean overturning and its contribution to a warm Southern Ocean, Clim. Past, 16, 1263–1283, https://doi.org/10.5194/cp-16-1263-2020, 2020.
Zhang, Y., Boer, A. M., Lunt, D. J., Hutchinson, D. K., Ross, P., Flierdt, T., Sexton, P., Coxall, H. K., Steinig, S., Ladant, J., Zhu, J., Donnadieu, Y., Zhang, Z., Chan, W., Abe-Ouchi, A., Niezgodzki, I., Lohmann, G., Knorr, G., Poulsen, C. J., and Huber, M.: Early Eocene Ocean Meridional Overturning Circulation: The Roles of Atmospheric Forcing and Strait Geometry, Paleoceanogr. Paleoclimatol., 37, e2021PA004329, https://doi.org/10.1029/2021PA004329, 2022.
Zhang, Y. G., Zhang, C. L., Liu, X.-L., Li, L., Hinrichs, K.-U., and Noakes, J. E.: Methane Index: A tetraether archaeal lipid biomarker indicator for detecting the instability of marine gas hydrates, Earth Planet. Sc. Lett., 307, 525–534, https://doi.org/10.1016/j.epsl.2011.05.031, 2011.
Zhang, Y. G., Pagani, M., and Wang, Z.: Ring Index: A new strategy to evaluate the integrity of TEX86 paleothermometry, Paleoceanography, 31, 220–232, https://doi.org/10.1002/2015PA002848, 2016.
Zhu, J., Poulsen, C. J., and Tierney, J. E.: Simulation of Eocene extreme warmth and high climate sensitivity through cloud feedbacks, Sci. Adv., 5, eaax1874, https://doi.org/10.1126/sciadv.aax1874, 2019.
Short summary
Polar amplification (PA) is a key uncertainty in climate projections. The factors that dominantly control PA are difficult to separate. Here we provide an estimate for the non-ice-related PA by reconstructing tropical ocean temperature variability from the ice-free early Eocene, which we compare to deep-ocean-derived high-latitude temperature variability across short-lived warming periods. We find a PA factor of 1.7–2.3 on 20 kyr timescales, which is somewhat larger than model estimates.
Polar amplification (PA) is a key uncertainty in climate projections. The factors that...