Articles | Volume 19, issue 4
https://doi.org/10.5194/cp-19-787-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-19-787-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Lipid-biomarker-based sea surface temperature record offshore Tasmania over the last 23 million years
Department of Earth Sciences, Utrecht University, Utrecht, 3584CB, the Netherlands
Foteini Lamprou
Department of Earth Sciences, Utrecht University, Utrecht, 3584CB, the Netherlands
Frida S. Hoem
Department of Earth Sciences, Utrecht University, Utrecht, 3584CB, the Netherlands
Mohammad Rizky Nanda Hadju
Department of Earth Sciences, Utrecht University, Utrecht, 3584CB, the Netherlands
Francesca Sangiorgi
Department of Earth Sciences, Utrecht University, Utrecht, 3584CB, the Netherlands
Francien Peterse
Department of Earth Sciences, Utrecht University, Utrecht, 3584CB, the Netherlands
Peter K. Bijl
Department of Earth Sciences, Utrecht University, Utrecht, 3584CB, the Netherlands
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Based on dinoflagellate cyst assemblage and sea surface temperature record west 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 the 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.
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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.
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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.
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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.
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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.
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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.
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Clim. Past Discuss., https://doi.org/10.5194/cp-2024-33, https://doi.org/10.5194/cp-2024-33, 2024
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Based on dinoflagellate cyst assemblage and sea surface temperature record west 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 the 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.
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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.
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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.
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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.
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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.
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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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
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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.
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.
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.
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.
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
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.
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.
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.
Thomas M. Hoyle, Manuel Sala-Pérez, and Francesca Sangiorgi
J. Micropalaeontol., 38, 55–65, https://doi.org/10.5194/jm-38-55-2019, https://doi.org/10.5194/jm-38-55-2019, 2019
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Morphology of dinoflagellate cysts (which are valuable tools in deciphering past environmental and climate changes) depends not only on genetics, but also on a range of environmental factors. We review frequently occurring (Black Sea) morphotypes and propose use of matrices to record gradual variation between endmember forms as a pragmatic approach until cyst–theca studies and genetic sequencing can demonstrate relationships between genetically and environmentally controlled morphotypes.
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.
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.
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.
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.
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.
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.
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
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
Related subject area
Subject: Ocean Dynamics | Archive: Marine Archives | Timescale: Cenozoic
Nonlinear increase in seawater 87Sr ∕ 86Sr in the Oligocene to early Miocene and implications for climate-sensitive weathering
Limited exchange between the deep Pacific and Atlantic oceans during the warm mid-Pliocene and Marine Isotope Stage M2 “glaciation”
Late Cenozoic sea-surface-temperature evolution of the South Atlantic Ocean
Buoyancy forcing: a key driver of northern North Atlantic sea surface temperature variability across multiple timescales
Late Neogene nannofossil assemblages as tracers of ocean circulation and paleoproductivity over the NW Australian shelf
Plio-Pleistocene Perth Basin water temperatures and Leeuwin Current dynamics (Indian Ocean) derived from oxygen and clumped-isotope paleothermometry
Temperate Oligocene surface ocean conditions offshore of Cape Adare, Ross Sea, Antarctica
A revised mid-Pliocene composite section centered on the M2 glacial event for ODP Site 846
Lessons from a high-CO2 world: an ocean view from ∼ 3 million years ago
Late Pliocene Cordilleran Ice Sheet development with warm northeast Pacific sea surface temperatures
Understanding the mechanisms behind high glacial productivity in the southern Brazilian margin
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 3: Insights from Oligocene–Miocene TEX86-based sea surface temperature reconstructions
Paleoceanography and ice sheet variability offshore Wilkes Land, Antarctica – Part 2: Insights from Oligocene–Miocene dinoflagellate cyst assemblages
Variations in Mediterranean–Atlantic exchange across the late Pliocene climate transition
Revisiting the Ceara Rise, equatorial Atlantic Ocean: isotope stratigraphy of ODP Leg 154 from 0 to 5 Ma
Constraints on ocean circulation at the Paleocene–Eocene Thermal Maximum from neodymium isotopes
Expansion and diversification of high-latitude radiolarian assemblages in the late Eocene linked to a cooling event in the southwest Pacific
Microfossil evidence for trophic changes during the Eocene–Oligocene transition in the South Atlantic (ODP Site 1263, Walvis Ridge)
A major change in North Atlantic deep water circulation 1.6 million years ago
Contribution of changes in opal productivity and nutrient distribution in the coastal upwelling systems to Late Pliocene/Early Pleistocene climate cooling
Productivity response of calcareous nannoplankton to Eocene Thermal Maximum 2 (ETM2)
Technical note: Late Pliocene age control and composite depths at ODP Site 982, revisited
Pliocene three-dimensional global ocean temperature reconstruction
Heather M. Stoll, Leopoldo D. Pena, Ivan Hernandez-Almeida, José Guitián, Thomas Tanner, and Heiko Pälike
Clim. Past, 20, 25–36, https://doi.org/10.5194/cp-20-25-2024, https://doi.org/10.5194/cp-20-25-2024, 2024
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The Oligocene and early Miocene periods featured dynamic glacial cycles on Antarctica. In this paper, we use Sr isotopes in marine carbonate sediments to document a change in the location and intensity of continental weathering during short periods of very intense Antarctic glaciation. Potentially, the weathering intensity of old continental rocks on Antarctica was reduced during glaciation. We also show improved age models for correlation of Southern Ocean and North Atlantic sediments.
Anna Hauge Braaten, Kim A. Jakob, Sze Ling Ho, Oliver Friedrich, Eirik Vinje Galaasen, Stijn De Schepper, Paul A. Wilson, and Anna Nele Meckler
Clim. Past, 19, 2109–2125, https://doi.org/10.5194/cp-19-2109-2023, https://doi.org/10.5194/cp-19-2109-2023, 2023
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In the context of understanding current global warming, the middle Pliocene (3.3–3.0 million years ago) is an important interval in Earth's history because atmospheric carbon dioxide concentrations were similar to levels today. We have reconstructed deep-sea temperatures at two different locations for this period, and find that a very different mode of ocean circulation or mixing existed, with important implications for how heat was transported in the deep ocean.
Frida S. Hoem, Adrián López-Quirós, Suzanna van de Lagemaat, Johan Etourneau, Marie-Alexandrine Sicre, Carlota Escutia, Henk Brinkhuis, Francien Peterse, Francesca Sangiorgi, and Peter K. Bijl
Clim. Past, 19, 1931–1949, https://doi.org/10.5194/cp-19-1931-2023, https://doi.org/10.5194/cp-19-1931-2023, 2023
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We present two new sea surface temperature (SST) records in comparison with available SST records to reconstruct South Atlantic paleoceanographic evolution. Our results show a low SST gradient in the Eocene–early Oligocene due to the persistent gyral circulation. A higher SST gradient in the Middle–Late Miocene infers a stronger circumpolar current. The southern South Atlantic was the coldest region in the Southern Ocean and likely the main deep-water formation location in the Middle Miocene.
Bjørg Risebrobakken, Mari F. Jensen, Helene R. Langehaug, Tor Eldevik, Anne Britt Sandø, Camille Li, Andreas Born, Erin Louise McClymont, Ulrich Salzmann, and Stijn De Schepper
Clim. Past, 19, 1101–1123, https://doi.org/10.5194/cp-19-1101-2023, https://doi.org/10.5194/cp-19-1101-2023, 2023
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In the observational period, spatially coherent sea surface temperatures characterize the northern North Atlantic at multidecadal timescales. We show that spatially non-coherent temperature patterns are seen both in further projections and a past warm climate period with a CO2 level comparable to the future low-emission scenario. Buoyancy forcing is shown to be important for northern North Atlantic temperature patterns.
Boris-Theofanis Karatsolis and Jorijntje Henderiks
Clim. Past, 19, 765–786, https://doi.org/10.5194/cp-19-765-2023, https://doi.org/10.5194/cp-19-765-2023, 2023
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Ocean circulation around NW Australia plays a key role in regulating the climate in the area and is characterised by seasonal variations in the activity of a major boundary current named the Leeuwin Current. By investigating nannofossils found in sediment cores recovered from the NW Australian shelf, we reconstructed ocean circulation in the warmer-than-present world from 6 to 3.5 Ma, as mirrored by long-term changes in stratification and nutrient availability.
David De Vleeschouwer, Marion Peral, Marta Marchegiano, Angelina Füllberg, Niklas Meinicke, Heiko Pälike, Gerald Auer, Benjamin Petrick, Christophe Snoeck, Steven Goderis, and Philippe Claeys
Clim. Past, 18, 1231–1253, https://doi.org/10.5194/cp-18-1231-2022, https://doi.org/10.5194/cp-18-1231-2022, 2022
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The Leeuwin Current transports warm water along the western coast of Australia: from the tropics to the Southern Hemisphere midlatitudes. Therewith, the current influences climate in two ways: first, as a moisture source for precipitation in southwestern Australia; second, as a vehicle for Equator-to-pole heat transport. In this study, we study sediment cores along the Leeuwin Current pathway to understand its ocean–climate interactions between 4 and 2 Ma.
Frida S. Hoem, Luis Valero, Dimitris Evangelinos, Carlota Escutia, Bella Duncan, Robert M. McKay, Henk Brinkhuis, Francesca Sangiorgi, and Peter K. Bijl
Clim. Past, 17, 1423–1442, https://doi.org/10.5194/cp-17-1423-2021, https://doi.org/10.5194/cp-17-1423-2021, 2021
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We present new offshore palaeoceanographic reconstructions for the Oligocene (33.7–24.4 Ma) in the Ross Sea, Antarctica. Our study of dinoflagellate cysts and lipid biomarkers indicates warm-temperate sea surface conditions. We posit that warm surface-ocean conditions near the continental shelf during the Oligocene promoted increased precipitation and heat delivery towards Antarctica that led to dynamic terrestrial ice sheet volumes in the warmer climate state of the Oligocene.
Timothy D. Herbert, Rocio Caballero-Gill, and Joseph B. Novak
Clim. Past, 17, 1385–1394, https://doi.org/10.5194/cp-17-1385-2021, https://doi.org/10.5194/cp-17-1385-2021, 2021
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The Pliocene represents a geologically warm period with polar ice restricted to the Antarctic. Nevertheless, variability and ice volume persisted in the Pliocene. This work revisits a classic site on which much of our understanding of Pliocene paleoclimate variability is based and corrects errors in data sets related to ice volume and ocean surface temperature. In particular, it generates an improved representation of an enigmatic glacial episode in Pliocene times (circa 3.3 Ma).
Erin L. McClymont, Heather L. Ford, Sze Ling Ho, Julia C. Tindall, Alan M. Haywood, Montserrat Alonso-Garcia, Ian Bailey, Melissa A. Berke, Kate Littler, Molly O. Patterson, Benjamin Petrick, Francien Peterse, A. Christina Ravelo, Bjørg Risebrobakken, Stijn De Schepper, George E. A. Swann, Kaustubh Thirumalai, Jessica E. Tierney, Carolien van der Weijst, Sarah White, Ayako Abe-Ouchi, Michiel L. J. Baatsen, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Ran Feng, Chuncheng Guo, Anna S. von der Heydt, Stephen Hunter, Xiangyi Li, Gerrit Lohmann, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Christian Stepanek, and Zhongshi Zhang
Clim. Past, 16, 1599–1615, https://doi.org/10.5194/cp-16-1599-2020, https://doi.org/10.5194/cp-16-1599-2020, 2020
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We examine the sea-surface temperature response to an interval of climate ~ 3.2 million years ago, when CO2 concentrations were similar to today and the near future. Our geological data and climate models show that global mean sea-surface temperatures were 2.3 to 3.2 ºC warmer than pre-industrial climate, that the mid-latitudes and high latitudes warmed more than the tropics, and that the warming was particularly enhanced in the North Atlantic Ocean.
Maria Luisa Sánchez-Montes, Erin L. McClymont, Jeremy M. Lloyd, Juliane Müller, Ellen A. Cowan, and Coralie Zorzi
Clim. Past, 16, 299–313, https://doi.org/10.5194/cp-16-299-2020, https://doi.org/10.5194/cp-16-299-2020, 2020
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In this paper, we present new climate reconstructions in SW Alaska from recovered marine sediments in the Gulf of Alaska. We find that glaciers reached the Gulf of Alaska during a cooling climate 2.9 million years ago, and after that the Cordilleran Ice Sheet continued growing during a global drop in atmospheric CO2 levels. Cordilleran Ice Sheet growth could have been supported by an increase in heat supply to the SW Alaska and warm ocean evaporation–mountain precipitation mechanisms.
Rodrigo da Costa Portilho-Ramos, Tainã Marcos Lima Pinho, Cristiano Mazur Chiessi, and Cátia Fernandes Barbosa
Clim. Past, 15, 943–955, https://doi.org/10.5194/cp-15-943-2019, https://doi.org/10.5194/cp-15-943-2019, 2019
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Fossil microorganisms from the last glacial found in marine sediments collected off southern Brazil suggest that more productive austral summer upwelling and more frequent austral winter incursions of nutrient-rich waters from the Plata River boosted regional productivity year-round. While upwelling was more productive due to the higher silicon content from the Southern Ocean, more frequent riverine incursions were modulated by stronger alongshore southwesterly winds.
Julian D. Hartman, Francesca Sangiorgi, Ariadna Salabarnada, Francien Peterse, Alexander J. P. Houben, Stefan Schouten, Henk Brinkhuis, Carlota Escutia, and Peter K. Bijl
Clim. Past, 14, 1275–1297, https://doi.org/10.5194/cp-14-1275-2018, https://doi.org/10.5194/cp-14-1275-2018, 2018
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We reconstructed sea surface temperatures for the Oligocene and Miocene periods (34–11 Ma) based on archaeal lipids from a site close to the Wilkes Land coast, Antarctica. Our record suggests generally warm to temperate surface waters: on average 17 °C. Based on the lithology, glacial and interglacial temperatures could be distinguished, showing an average 3 °C offset. The long-term temperature trend resembles the benthic δ18O stack, which may have implications for ice volume reconstructions.
Peter K. Bijl, Alexander J. P. Houben, Julian D. Hartman, Jörg Pross, Ariadna Salabarnada, Carlota Escutia, and Francesca Sangiorgi
Clim. Past, 14, 1015–1033, https://doi.org/10.5194/cp-14-1015-2018, https://doi.org/10.5194/cp-14-1015-2018, 2018
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We document Southern Ocean surface ocean conditions and changes therein during the Oligocene and Miocene (34–10 Myr ago). We infer profound long-term and short-term changes in ice-proximal oceanographic conditions: sea surface temperature, nutrient conditions and sea ice. Our results point to warm-temperate, oligotrophic, ice-proximal oceanographic conditions. These distinct oceanographic conditions may explain the high amplitude in inferred Oligocene–Miocene Antarctic ice volume changes.
Ángela García-Gallardo, Patrick Grunert, and Werner E. Piller
Clim. Past, 14, 339–350, https://doi.org/10.5194/cp-14-339-2018, https://doi.org/10.5194/cp-14-339-2018, 2018
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We study the variability in Mediterranean–Atlantic exchange, focusing on the surface Atlantic inflow across the mid-Pliocene warm period and the onset of the Northern Hemisphere glaciation, still unresolved by previous works. Oxygen isotope gradients between both sides of the Strait of Gibraltar reveal weak inflow during warm periods that turns stronger during severe glacials and the start of a negative feedback between exchange at the Strait and the Atlantic Meridional Overturning Circulation.
Roy H. Wilkens, Thomas Westerhold, Anna J. Drury, Mitchell Lyle, Thomas Gorgas, and Jun Tian
Clim. Past, 13, 779–793, https://doi.org/10.5194/cp-13-779-2017, https://doi.org/10.5194/cp-13-779-2017, 2017
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Here we introduce the Code for Ocean Drilling Data (CODD), a unified and consistent system for integrating disparate data streams such as micropaleontology, physical properties, core images, geochemistry, and borehole logging. As a test case, data from Ocean Drilling Program Leg 154 (Ceara Rise – western equatorial Atlantic) were assembled into a new regional composite benthic stable isotope record covering the last 5 million years.
April N. Abbott, Brian A. Haley, Aradhna K. Tripati, and Martin Frank
Clim. Past, 12, 837–847, https://doi.org/10.5194/cp-12-837-2016, https://doi.org/10.5194/cp-12-837-2016, 2016
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The Paleocene-Eocene Thermal Maximum (PETM) was a brief period when the Earth was in an extreme greenhouse state. We use neodymium isotopes to suggest that during this time deep-ocean circulation was distinct in each basin (North and South Atlanic, Southern, Pacific) with little exchange between. Moreover, the Pacific data show the most variability, suggesting this was a critical region possibly involved in both PETM triggering and remediation.
K. M. Pascher, C. J. Hollis, S. M. Bohaty, G. Cortese, R. M. McKay, H. Seebeck, N. Suzuki, and K. Chiba
Clim. Past, 11, 1599–1620, https://doi.org/10.5194/cp-11-1599-2015, https://doi.org/10.5194/cp-11-1599-2015, 2015
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Radiolarian taxa with high-latitude affinities are present from at least the middle Eocene in the SW Pacific and become very abundant in the late Eocene at all investigated sites. A short incursion of low-latitude taxa is observed during the MECO and late Eocene warming event at Site 277. Radiolarian abundance, diversity and taxa with high-latitude affinities increase at Site 277 in two steps in the latest Eocene due to climatic cooling and expansion of cold water masses.
M. Bordiga, J. Henderiks, F. Tori, S. Monechi, R. Fenero, A. Legarda-Lisarri, and E. Thomas
Clim. Past, 11, 1249–1270, https://doi.org/10.5194/cp-11-1249-2015, https://doi.org/10.5194/cp-11-1249-2015, 2015
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Deep-sea sediments at ODP Site 1263 (Walvis Ridge, South Atlantic) show that marine calcifying algae decreased in abundance and size at the Eocene-Oligocene boundary, when the Earth transitioned from a greenhouse to a more glaciated and cooler climate. This decreased the food supply for benthic foraminifer communities. The plankton rapidly responded to fast-changing conditions, such as seasonal nutrient availability, or to threshold-levels in pCO2, cooling and ocean circulation.
N. Khélifi and M. Frank
Clim. Past, 10, 1441–1451, https://doi.org/10.5194/cp-10-1441-2014, https://doi.org/10.5194/cp-10-1441-2014, 2014
J. Etourneau, C. Ehlert, M. Frank, P. Martinez, and R. Schneider
Clim. Past, 8, 1435–1445, https://doi.org/10.5194/cp-8-1435-2012, https://doi.org/10.5194/cp-8-1435-2012, 2012
M. Dedert, H. M. Stoll, D. Kroon, N. Shimizu, K. Kanamaru, and P. Ziveri
Clim. Past, 8, 977–993, https://doi.org/10.5194/cp-8-977-2012, https://doi.org/10.5194/cp-8-977-2012, 2012
N. Khélifi, M. Sarnthein, and B. D. A. Naafs
Clim. Past, 8, 79–87, https://doi.org/10.5194/cp-8-79-2012, https://doi.org/10.5194/cp-8-79-2012, 2012
H. J. Dowsett, M. M. Robinson, and K. M. Foley
Clim. Past, 5, 769–783, https://doi.org/10.5194/cp-5-769-2009, https://doi.org/10.5194/cp-5-769-2009, 2009
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Short summary
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.
Neogene climate cooling is thought to be accompanied by increased Equator-to-pole temperature...