Articles | Volume 16, issue 6
https://doi.org/10.5194/cp-16-2415-2020
© Author(s) 2020. 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-16-2415-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note
| 
02 Dec 2020
Technical note |
| 02 Dec 2020
| 02 Dec 2020
Technical note: A new automated radiolarian image acquisition, stacking, processing, segmentation and identification workflow
Aix Marseille Univ, CNRS, IRD, Coll France, INRAE, CEREGE, Aix-en-Provence, France
Ross Marchant
Aix Marseille Univ, CNRS, IRD, Coll France, INRAE, CEREGE, Aix-en-Provence, France
present address: School of Electrical Engineering and Robotics, Queensland University of Technology, Brisbane, Australia
Giuseppe Cortese
GNS Science, Lower Hutt, New Zealand
Yves Gally
Aix Marseille Univ, CNRS, IRD, Coll France, INRAE, CEREGE, Aix-en-Provence, France
Thibault de Garidel-Thoron
Aix Marseille Univ, CNRS, IRD, Coll France, INRAE, CEREGE, Aix-en-Provence, France
Luc Beaufort
Aix Marseille Univ, CNRS, IRD, Coll France, INRAE, CEREGE, Aix-en-Provence, France
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EGUsphere, https://doi.org/10.5194/egusphere-2023-2981, https://doi.org/10.5194/egusphere-2023-2981, 2024
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Paleo-oxygen proxies can extend current records, bound pre-anthropogenic baselines, provide datasets necessary to test climate models under different boundary conditions, and ultimately understand how ocean oxygenation responds on longer timescales. Here we summarize current proxies used for the reconstruction of Cenozoic seawater oxygen levels. This includes an overview of the proxy's history, how it works, resources required, limitations, and future recommendations.
Martin Tetard, Laetitia Licari, Ekaterina Ovsepyan, Kazuyo Tachikawa, and Luc Beaufort
Biogeosciences, 18, 2827–2841, https://doi.org/10.5194/bg-18-2827-2021, https://doi.org/10.5194/bg-18-2827-2021, 2021
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Oxygen minimum zones are oceanic regions almost devoid of dissolved oxygen and are currently expanding due to global warming. Investigation of their past behaviour will allow better understanding of these areas and better prediction of their future evolution. A new method to estimate past [O2] was developed based on morphometric measurements of benthic foraminifera. This method and two other approaches based on foraminifera assemblages and porosity were calibrated using 45 core tops worldwide.
Ross Marchant, Martin Tetard, Adnya Pratiwi, Michael Adebayo, and Thibault de Garidel-Thoron
J. Micropalaeontol., 39, 183–202, https://doi.org/10.5194/jm-39-183-2020, https://doi.org/10.5194/jm-39-183-2020, 2020
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Foraminifera are marine microorganisms with a calcium carbonate shell. Their fossil remains build up on the seafloor, forming kilometres of sediment over time. From analysis of the foraminiferal record we can estimate past climate conditions and the geological history of the Earth. We have developed an artificial intelligence system for automatically identifying foraminifera species, replacing the time-consuming manual approach and thus helping to make these analyses more efficient and accurate.
Celina Rebeca Valença, Luc Beaufort, Gustaaf Marinus Hallegraeff, and Marius Nils Müller
Biogeosciences, 21, 1601–1611, https://doi.org/10.5194/bg-21-1601-2024, https://doi.org/10.5194/bg-21-1601-2024, 2024
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Coccolithophores contribute to the global carbon cycle and their calcite structures (coccoliths) are used as a palaeoproxy to understand past oceanographic conditions. Here, we compared three frequently used methods to estimate coccolith mass from the model species Emiliania huxleyi and the results allow for a high level of comparability between the methods, facilitating future comparisons and consolidation of mass changes observed from ecophysiological and biogeochemical studies.
Babette Hoogakker, Catherine Davis, Yi Wang, Stepanie Kusch, Katrina Nilsson-Kerr, Dalton Hardisty, Allison Jacobel, Dharma Reyes Macaya, Nicolaas Glock, Sha Ni, Julio Sepúlveda, Abby Ren, Alexandra Auderset, Anya Hess, Katrina Meissner, Jorge Cardich, Robert Anderson, Christine Barras, Chandranath Basak, Harold Bradbury, Inda Brinkmann, Alexis Castillo, Madelyn Cook, Kassandra Costa, Constance Choquel, Paula Diz, Jonas Donnenfield, Felix Elling, Zeynep Erdem, Helena Filipsson, Sebastian Garrido, Julia Gottschalk, Anjaly Govindankutty Menon, Jeroen Groeneveld, Christian Hallman, Ingrid Hendy, Rick Hennekam, Wanyi Lu, Jean Lynch-Stieglitz, Lelia Matos, Alfredo Martínez-García, Giulia Molina, Práxedes Muñoz, Simone Moretti, Jennifer Morford, Sophie Nuber, Svetlana Radionovskaya, Morgan Raven, Christopher Somes, Anja Studer, Kazuyo Tachikawa, Raúl Tapia, Martin Tetard, Tyler Vollmer, Shuzhuang Wu, Yan Zhang, Xin-Yuan Zheng, and Yuxin Zhou
EGUsphere, https://doi.org/10.5194/egusphere-2023-2981, https://doi.org/10.5194/egusphere-2023-2981, 2024
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Paleo-oxygen proxies can extend current records, bound pre-anthropogenic baselines, provide datasets necessary to test climate models under different boundary conditions, and ultimately understand how ocean oxygenation responds on longer timescales. Here we summarize current proxies used for the reconstruction of Cenozoic seawater oxygen levels. This includes an overview of the proxy's history, how it works, resources required, limitations, and future recommendations.
Luc Beaufort and Anta Clarisse Sarr
Clim. Past Discuss., https://doi.org/10.5194/cp-2023-80, https://doi.org/10.5194/cp-2023-80, 2023
Revised manuscript under review for CP
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At present, under low eccentricity, the tropical ocean experiences a limited seasonality. Based on 8 climate simulations of sea surface temperature and primary production, we show that during high eccentricity times, significant seasons existed in the tropics due to annual changes in the Earth-Sun distance. Those tropical seasons are slowly shifting on the calendar year that is distinct from classical seasons. Their past dynamics should have influenced phenomena like ENSO and monsoons.
Kelly-Anne Lawler, Giuseppe Cortese, Matthieu Civel-Mazens, Helen Bostock, Xavier Crosta, Amy Leventer, Vikki Lowe, John Rogers, and Leanne K. Armand
Earth Syst. Sci. Data, 13, 5441–5453, https://doi.org/10.5194/essd-13-5441-2021, https://doi.org/10.5194/essd-13-5441-2021, 2021
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Radiolarians found in marine sediments are used to reconstruct past Southern Ocean environments. This requires a comprehensive modern dataset. The Southern Ocean Radiolarian (SO-RAD) dataset includes radiolarian counts from sites in the Southern Ocean. It can be used for palaeoceanographic reconstructions or to study modern species diversity and abundance. We describe the data collection and include recommendations for users unfamiliar with procedures typically used by the radiolarian community.
Martin Tetard, Laetitia Licari, Ekaterina Ovsepyan, Kazuyo Tachikawa, and Luc Beaufort
Biogeosciences, 18, 2827–2841, https://doi.org/10.5194/bg-18-2827-2021, https://doi.org/10.5194/bg-18-2827-2021, 2021
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Oxygen minimum zones are oceanic regions almost devoid of dissolved oxygen and are currently expanding due to global warming. Investigation of their past behaviour will allow better understanding of these areas and better prediction of their future evolution. A new method to estimate past [O2] was developed based on morphometric measurements of benthic foraminifera. This method and two other approaches based on foraminifera assemblages and porosity were calibrated using 45 core tops worldwide.
Luc Beaufort, Yves Gally, Baptiste Suchéras-Marx, Patrick Ferrand, and Julien Duboisset
Biogeosciences, 18, 775–785, https://doi.org/10.5194/bg-18-775-2021, https://doi.org/10.5194/bg-18-775-2021, 2021
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The coccoliths are major contributors to the particulate inorganic carbon in the ocean. They are extremely difficult to weigh because they are too small to be manipulated. We propose a universal method to measure thickness and weight of fine calcite using polarizing microscopy that does not require fine-tuning of the light or a calibration process. This method named "bidirectional circular polarization" uses two images taken with two directions of a circular polarizer.
Abhijith U. Venugopal, Nancy A. N. Bertler, Rebecca L. Pyne, Helle A. Kjær, V. Holly L. Winton, Paul A. Mayewski, and Giuseppe Cortese
Clim. Past Discuss., https://doi.org/10.5194/cp-2020-151, https://doi.org/10.5194/cp-2020-151, 2020
Manuscript not accepted for further review
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We present a new and highly resolved glacial record of nitrate and calcium from a deep ice core obtained from Roosevelt Island, West Antarctica. Our data show a dependent association among nitrate and non-sea salt calcium (mineral dust) as observed previously in East Antarctica. The spatial pattern indicates that mineral dust is scavenging nitrate from the atmosphere and the westerlies are dispersing the dust-bound nitrate across Antarctica, making nitrate a potential paleo-westerly wind proxy.
Xinquan Zhou, Stéphanie Duchamp-Alphonse, Masa Kageyama, Franck Bassinot, Luc Beaufort, and Christophe Colin
Clim. Past, 16, 1969–1986, https://doi.org/10.5194/cp-16-1969-2020, https://doi.org/10.5194/cp-16-1969-2020, 2020
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We provide a high-resolution primary productivity (PP) record of the northeastern Bay of Bengal over the last 26 000 years. Combined with climate model outputs, we show that PP over the glacial period is controlled by river input nutrients under low sea level conditions and after the Last Glacial Maximum is controlled by upper seawater salinity stratification related to monsoon precipitation. During the deglaciation the Atlantic meridional overturning circulation is the main forcing factor.
Ross Marchant, Martin Tetard, Adnya Pratiwi, Michael Adebayo, and Thibault de Garidel-Thoron
J. Micropalaeontol., 39, 183–202, https://doi.org/10.5194/jm-39-183-2020, https://doi.org/10.5194/jm-39-183-2020, 2020
Short summary
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Foraminifera are marine microorganisms with a calcium carbonate shell. Their fossil remains build up on the seafloor, forming kilometres of sediment over time. From analysis of the foraminiferal record we can estimate past climate conditions and the geological history of the Earth. We have developed an artificial intelligence system for automatically identifying foraminifera species, replacing the time-consuming manual approach and thus helping to make these analyses more efficient and accurate.
Priscilla Le Mézo, Luc Beaufort, Laurent Bopp, Pascale Braconnot, and Masa Kageyama
Clim. Past, 13, 759–778, https://doi.org/10.5194/cp-13-759-2017, https://doi.org/10.5194/cp-13-759-2017, 2017
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This paper focuses on the relationship between Arabian Sea biological productivity and the Indian summer monsoon in climates of the last 72 kyr. A general circulation model coupled to a biogeochemistry model simulates the changes in productivity and monsoon intensity and pattern. The paradigm stating that a stronger summer monsoon enhances productivity is not always verified in our simulations. This work highlights the importance of considering the monsoon pattern in addition to its intensity.
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.
K. J. S. Meier, L. Beaufort, S. Heussner, and P. Ziveri
Biogeosciences, 11, 2857–2869, https://doi.org/10.5194/bg-11-2857-2014, https://doi.org/10.5194/bg-11-2857-2014, 2014
K. Schmidt, C. L. De La Rocha, M. Gallinari, and G. Cortese
Biogeosciences, 11, 135–145, https://doi.org/10.5194/bg-11-135-2014, https://doi.org/10.5194/bg-11-135-2014, 2014
C. J. O'Brien, J. A. Peloquin, M. Vogt, M. Heinle, N. Gruber, P. Ajani, H. Andruleit, J. Arístegui, L. Beaufort, M. Estrada, D. Karentz, E. Kopczyńska, R. Lee, A. J. Poulton, T. Pritchard, and C. Widdicombe
Earth Syst. Sci. Data, 5, 259–276, https://doi.org/10.5194/essd-5-259-2013, https://doi.org/10.5194/essd-5-259-2013, 2013
Related subject area
Subject: Proxy Use-Development-Validation | Archive: Marine Archives | Timescale: Cenozoic
Paleocene–Eocene age glendonites from the Mid-Norwegian Margin – indicators of cold snaps in the hothouse?
Assessing environmental change associated with early Eocene hyperthermals in the Atlantic Coastal Plain, USA
Technical note: A new online tool for δ18O–temperature conversions
A 15-million-year surface- and subsurface-integrated TEX86 temperature record from the eastern equatorial Atlantic
Sclerochronological evidence of pronounced seasonality from the late Pliocene of the southern North Sea basin and its implications
Pliocene evolution of the tropical Atlantic thermocline depth
Maastrichtian–Rupelian paleoclimates in the southwest Pacific – a critical re-evaluation of biomarker paleothermometry and dinoflagellate cyst paleoecology at Ocean Drilling Program Site 1172
Southern Ocean bottom-water cooling and ice sheet expansion during the middle Miocene climate transition
Rapid and sustained environmental responses to global warming: the Paleocene–Eocene Thermal Maximum in the eastern North Sea
Atmospheric carbon dioxide variations across the middle Miocene climate transition
OPTiMAL: a new machine learning approach for GDGT-based palaeothermometry
Late Paleocene–early Eocene Arctic Ocean sea surface temperatures: reassessing biomarker paleothermometry at Lomonosov Ridge
Surface-circulation change in the southwest Pacific Ocean across the Middle Eocene Climatic Optimum: inferences from dinoflagellate cysts and biomarker paleothermometry
A new age model for the Pliocene of the southern North Sea basin: a multi-proxy climate reconstruction
Joint inversion of proxy system models to reconstruct paleoenvironmental time series from heterogeneous data
Mercury anomalies across the Palaeocene–Eocene Thermal Maximum
Reinforcing the North Atlantic backbone: revision and extension of the composite splice at ODP Site 982
Highly variable Pliocene sea surface conditions in the Norwegian Sea
The PRISM4 (mid-Piacenzian) paleoenvironmental reconstruction
Revisiting carbonate chemistry controls on planktic foraminifera Mg / Ca: implications for sea surface temperature and hydrology shifts over the Paleocene–Eocene Thermal Maximum and Eocene–Oligocene transition
The Paleocene–Eocene Thermal Maximum at DSDP Site 277, Campbell Plateau, southern Pacific Ocean
The bivalve Glycymeris planicostalis as a high-resolution paleoclimate archive for the Rupelian (Early Oligocene) of central Europe
Pliocene diatom and sponge spicule oxygen isotope ratios from the Bering Sea: isotopic offsets and future directions
Re-evaluation of the age model for North Atlantic Ocean Site 982 – arguments for a return to the original chronology
Exploring the controls on element ratios in middle Eocene samples of the benthic foraminifera Oridorsalis umbonatus
Application of Fourier Transform Infrared Spectroscopy (FTIR) for assessing biogenic silica sample purity in geochemical analyses and palaeoenvironmental research
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.
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.
Daniel E. Gaskell and Pincelli M. Hull
Clim. Past, 19, 1265–1274, https://doi.org/10.5194/cp-19-1265-2023, https://doi.org/10.5194/cp-19-1265-2023, 2023
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One of the most common ways of reconstructing temperatures in the geologic past is by analyzing oxygen isotope ratios in fossil shells. However, converting these data to temperatures can be a technically complicated task. Here, we present a new online tool that automates this task.
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.
Andrew L. A. Johnson, Annemarie M. Valentine, Bernd R. Schöne, Melanie J. Leng, and Stijn Goolaerts
Clim. Past, 18, 1203–1229, https://doi.org/10.5194/cp-18-1203-2022, https://doi.org/10.5194/cp-18-1203-2022, 2022
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Determining seasonal temperatures demands proxies that record the highest and lowest temperatures over the annual cycle. Many record neither, but oxygen isotope profiles from shells in principle record both. Oxygen isotope data from late Pliocene bivalve molluscs of the southern North Sea basin show that the seasonal temperature range was at times much higher than previously estimated and higher than now. This suggests reduced oceanic heat supply, in contrast to some previous interpretations.
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.
Peter K. Bijl, Joost Frieling, Margot J. 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.
Thomas J. Leutert, Sevasti Modestou, Stefano M. Bernasconi, and A. Nele Meckler
Clim. Past, 17, 2255–2271, https://doi.org/10.5194/cp-17-2255-2021, https://doi.org/10.5194/cp-17-2255-2021, 2021
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The Miocene climatic optimum associated with high atmospheric CO2 levels (~17–14 Ma) was followed by a period of dramatic climate change. We present a clumped isotope-based bottom-water temperature record from the Southern Ocean covering this key climate transition. Our record reveals warm conditions and a substantial cooling preceding the main ice volume increase, possibly caused by thresholds involved in ice growth and/or regional effects at our study site.
Ella W. Stokke, Morgan T. Jones, Lars Riber, Haflidi Haflidason, Ivar Midtkandal, Bo Pagh Schultz, and Henrik H. Svensen
Clim. Past, 17, 1989–2013, https://doi.org/10.5194/cp-17-1989-2021, https://doi.org/10.5194/cp-17-1989-2021, 2021
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In this paper, we present new sedimentological, geochemical, and mineralogical data exploring the environmental response to climatic and volcanic impact during the Paleocene–Eocene Thermal Maximum (~55.9 Ma; PETM). Our data suggest a rise in continental weathering and a shift to anoxic–sulfidic conditions. This indicates a rapid environmental response to changes in the carbon cycle and temperatures and highlights the important role of shelf areas as carbon sinks driving the PETM recovery.
Markus Raitzsch, Jelle Bijma, Torsten Bickert, Michael Schulz, Ann Holbourn, and Michal Kučera
Clim. Past, 17, 703–719, https://doi.org/10.5194/cp-17-703-2021, https://doi.org/10.5194/cp-17-703-2021, 2021
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At approximately 14 Ma, the East Antarctic Ice Sheet expanded to almost its current extent, but the role of CO2 in this major climate transition is not entirely known. We show that atmospheric CO2 might have varied on 400 kyr cycles linked to the eccentricity of the Earth’s orbit. The resulting change in weathering and ocean carbon cycle affected atmospheric CO2 in a way that CO2 rose after Antarctica glaciated, helping to stabilize the climate system on its way to the “ice-house” world.
Tom Dunkley Jones, Yvette L. Eley, William Thomson, Sarah E. Greene, Ilya Mandel, Kirsty Edgar, and James A. Bendle
Clim. Past, 16, 2599–2617, https://doi.org/10.5194/cp-16-2599-2020, https://doi.org/10.5194/cp-16-2599-2020, 2020
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We explore the utiliity of the composition of fossil lipid biomarkers, which are commonly preserved in ancient marine sediments, in providing estimates of past ocean temperatures. The group of lipids concerned show compositional changes across the modern oceans that are correlated, to some extent, with local surface ocean temperatures. Here we present new machine learning approaches to improve our understanding of this temperature sensitivity and its application to reconstructing past climates.
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.
Margot J. 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.
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.
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.
Anna Joy Drury, Thomas Westerhold, David Hodell, and Ursula Röhl
Clim. Past, 14, 321–338, https://doi.org/10.5194/cp-14-321-2018, https://doi.org/10.5194/cp-14-321-2018, 2018
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North Atlantic Site 982 is key to our understanding of climate evolution over the past 12 million years. However, the stratigraphy and age model are unverified. We verify the composite splice using XRF core scanning data and establish a revised benthic foraminiferal stable isotope astrochronology from 8.0–4.5 million years ago. Our new stratigraphy accurately correlates the Atlantic and the Mediterranean and suggests a connection between late Miocene cooling and dynamic ice sheet expansion.
Paul E. Bachem, Bjørg Risebrobakken, Stijn De Schepper, and Erin L. McClymont
Clim. Past, 13, 1153–1168, https://doi.org/10.5194/cp-13-1153-2017, https://doi.org/10.5194/cp-13-1153-2017, 2017
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We present a high-resolution multi-proxy study of the Norwegian Sea, covering the 5.33 to 3.14 Ma time window within the Pliocene. We show that large-scale climate transitions took place during this warmer than modern time, most likely in response to ocean gateway transformations. Strong warming at 4.0 Ma in the Norwegian Sea, when regions closer to Greenland cooled, indicate that increased northward ocean heat transport may be compatible with expanding glaciation and Arctic sea ice growth.
Harry Dowsett, Aisling Dolan, David Rowley, Robert Moucha, Alessandro M. Forte, Jerry X. Mitrovica, Matthew Pound, Ulrich Salzmann, Marci Robinson, Mark Chandler, Kevin Foley, and Alan Haywood
Clim. Past, 12, 1519–1538, https://doi.org/10.5194/cp-12-1519-2016, https://doi.org/10.5194/cp-12-1519-2016, 2016
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Past intervals in Earth history provide unique windows into conditions much different than those observed today. We investigated the paleoenvironments of a past warm interval (~ 3 million years ago). Our reconstruction includes data sets for surface temperature, vegetation, soils, lakes, ice sheets, topography, and bathymetry. These data are being used along with global climate models to expand our understanding of the climate system and to help us prepare for future changes.
David Evans, Bridget S. Wade, Michael Henehan, Jonathan Erez, and Wolfgang Müller
Clim. Past, 12, 819–835, https://doi.org/10.5194/cp-12-819-2016, https://doi.org/10.5194/cp-12-819-2016, 2016
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We show that seawater pH exerts a substantial control on planktic foraminifera Mg / Ca, a widely applied palaeothermometer. As a result, temperature reconstructions based on this proxy are likely inaccurate over climatic events associated with a significant change in pH. We examine the implications of our findings for hydrological and temperature shifts over the Paleocene-Eocene Thermal Maximum and for the degree of surface ocean precursor cooling before the Eocene-Oligocene transition.
C. J. Hollis, B. R. Hines, K. Littler, V. Villasante-Marcos, D. K. Kulhanek, C. P. Strong, J. C. Zachos, S. M. Eggins, L. Northcote, and A. Phillips
Clim. Past, 11, 1009–1025, https://doi.org/10.5194/cp-11-1009-2015, https://doi.org/10.5194/cp-11-1009-2015, 2015
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Re-examination of a Deep Sea Drilling Project sediment core (DSDP Site 277) from the western Campbell Plateau has identified the initial phase of the Paleocene-Eocene Thermal Maximum (PETM) within nannofossil chalk, the first record of the PETM in an oceanic setting in the southern Pacific Ocean (paleolatitude of ~65°S). Geochemical proxies indicate that intermediate and surface waters warmed by ~6° at the onset of the PETM prior to the full development of the negative δ13C excursion.
E. O. Walliser, B. R. Schöne, T. Tütken, J. Zirkel, K. I. Grimm, and J. Pross
Clim. Past, 11, 653–668, https://doi.org/10.5194/cp-11-653-2015, https://doi.org/10.5194/cp-11-653-2015, 2015
A. M. Snelling, G. E. A. Swann, J. Pike, and M. J. Leng
Clim. Past, 10, 1837–1842, https://doi.org/10.5194/cp-10-1837-2014, https://doi.org/10.5194/cp-10-1837-2014, 2014
K. T. Lawrence, I. Bailey, and M. E. Raymo
Clim. Past, 9, 2391–2397, https://doi.org/10.5194/cp-9-2391-2013, https://doi.org/10.5194/cp-9-2391-2013, 2013
C. F. Dawber and A. K. Tripati
Clim. Past, 8, 1957–1971, https://doi.org/10.5194/cp-8-1957-2012, https://doi.org/10.5194/cp-8-1957-2012, 2012
G. E. A. Swann and S. V. Patwardhan
Clim. Past, 7, 65–74, https://doi.org/10.5194/cp-7-65-2011, https://doi.org/10.5194/cp-7-65-2011, 2011
Cited articles
Abelmann, A:. Radiolarian taxa from Southern Ocean sediment traps (Atlantic sector), Polar Biol., 12, 373–385, 1992. a
Abelmann, A. and Nimmergut, A.: Radiolarians in the Sea of Okhotsk and their ecological implication for paleoenvironmental reconstructions, Deep-Sea Res. Pt. II, 52, 2302–2331, 2005. a
Abelmann, A., Brathauer, U., Gersonde, R., Siegier, R., and Zielinski, U.: Radiolarian-based transfer function for the estimation of sea surface temperatures in the Southern Ocean (Atlantic Sector), Paleoceanography, 14, 410–421, 1999. a
Apostol, L. A., Marquez, E., Gasmen, P., and Solano, G.: Radss: A radiolarian classifier using support vector machines, 7th International Conference on Information, Intelligence, Systems & Applications (IISA), 13–15 July 2016, Chalkidiki, Greece, 2016. a
Beaufort, L. and Dollfus, D.: Automatic recognition of coccoliths by dynamical neural networks, Mar. Micropaleontol., 51, 57–73, 2004. a
Beaufort, L., Chen, M. T., Chivas, A., and Manighetti, B.: Campagne IPHIS – IMAGES Ill/MD 106 du 23-05-97 au 28-06-97. Les Publications de l'Institut francais pour la recherche et la technologie polaires, Les Rapports des campagnes a la mer, 151 pp., available at: https://archimer.ifremer.fr/doc/00629/74140/ (last access: 17 November 2020), 1997. a
Beaufort, L., de Garidel-Thoron, T., Mix, A. C., and Pisias, N. G.: ENSO-like forcing on oceanic primary production during the Late Pleistocene, Science 293, 2440–2444, 2001. a
Beaufort, L., Barbarin, N., and Gally, Y.: Optical measurements to determine the thickness of calcite crystals and the mass of thin carbonate particles such as coccoliths, Nat. Protoc., 9, 633–642, 2014. a
Bjørklund, K. R. and Goll, R. M.: Internal skeletal structures of Collosphaera and Trisolenia: A case of repetitive evolution in the Collosphaeridae (Radiolaria), J. Paleontol., 53, 1293–1326, 1979. a
Boltovskoy, D. and Jankilevich, S. S.: Radiolarian distribution in east equatorial Pacific plankton, Oceanol. Acta, 8, 101–123, 1985. a
Boltovskoy, D., Kling, S. A., Takahashi, K., and Bjorklund, K.: World atlas of distribution of living radiolaria, Palaeontol. Electron., 13, 1–230, 2010. a
Boltovskoy, D., Anderson, O. R., and Correa, N. M.: Radiolaria and Phaeodaria, in: Handbook of the Protists, edited by: Archibald, J. M. and Simpson, A. G. B., Slamovits, C., Springer, 1–33, 2017. a
Bourel, B., Marchant, R., de Garidel-Thoron, T., Tetard, M., Barboni, D., Gally, Y., and Beaufort, L.: Automated recognition by multiple convolutional neural networks of modern, fossil, intact and damaged pollen grains, Comput. Geosci., 140, 104498, https://doi.org/10.1016/j.cageo.2020.104498, 2020. a
Budai, A., Riedel, W. R., and Westberg, M. J.: A general-purpose paleontologic information decide, J. Paleontol., 54, 259–262, 1980. a
Campbell, A. S.: Radiolaria, Part D: Protista 3, in: Treatise on Invertebrate Paleontology, edited by: Moore, R. C., Geological Society of America, University of Kansas Press, Lawrence, USA, DI-DI63, 1954. a
Caulet, J. P. and Nigrini, C.: The genus Pterocorys (Radiolaria) from the tropical Late Neogene of the Indian and Pacific Oceans, Micropaleontology, 34, 217–235, 1988. a
Caulet, J. P., Vénec-Peyré, M. T., Vergnaud-Grazzini, C., and Nigrini, C.: Variation of South Somalian upwelling during the last 160 ka: Radiolarian and foraminifera records in Core MD-85674, in: Upwelling Systems: Evolution Since the Early Miocene, edited by: Summerhayes, C. P., Prell,W. L., and Emeis, K. C., Geol. Soc. Spec. Publ., 64, Geological Society, London, UK, 379–389, 1992. a
Caulet, J. P., Sanfilippo, A., and Nigrini, C.: “Radworld”, a taxonomic relational database for radiolarians, in: InterRad II and Triassic Stratigraphy Symposium: a joint international conference hosted by the International Association of Radiolarian Paleontologists, IGCP 467 and the Subcommission of Triassic Stratigraphy, edited by: Lüer, V., Hollis, C., Campbell, H., and Simes, J., GNS Science, Lower Hutt, New Zealand, p. 47, 2006. a
Dieleman, S., De Fauw, J., and Kavukcuoglu, K.: Exploiting Cyclic Symmetry in Convolutional Neural Networks, arXiv [preprint], arXiv:1602.02660, 8 February 2016. a
Dollfus, D. and Beaufort, L.: Fat neural network for recognition of position-normalised objects, Neural Networks, 12, 553–560, 1999. a
Dolven, J. K. and Skjerpen, H. A.: An online micropaleontology database: Radiolaria.org, Eclogae Geol. Helv., Supplement 1, 63–66, 2006. a
He, K., Zhang, X., Ren, S., and Sun, J.: Deep Residual Learning for Image Recognition, arXiv [preprint], arXiv:1512.03385, 10 December 2015. a
Hernández-Almeida, I., Bjørklund, K. R., Sierro, F. J., Filippelli, G. M., Cacho, I., and Flores, J. A.: A high resolution opal and radiolarian record from the subpolar North Atlantic during the Mid-Pleistocene Transition (1069–779 ka): Palaeoceanographic implications, Palaeogeogr. Palaeocl., 391, 49–70, 2013. a
Itaki, T., Matsuoka, A., Yoshida, K., Machidori, S., Shinzawa, M., and Todo, T.: Late spring radiolarian fauna in the surface water off Tassha, Aikawa Town, Sado Island, central Japan, Sci. Rep. Niigata Univ. (Geol.), 17, 41–51, 2003. a
Keceli, A. S., Kaya, A., and Keceli, S.U.: Classification of radiolarian images with hand-crafted and deep features, Comput. Geosci., 109, 67–74, 2017. a
Lazarus, D.: A brief review of radiolarian research, Paläontol. Z., 79, 183–200, 2005.
Lazarus, D., Spencer-Cervato, C., Pika-Biolzi, M., Beckmann, J. P., Von Salis, K., Hilbrecht, H., and Thierstein, H.: Revised chronology of Neogene DSDP Holes from the world ocean, Ocean Drilling Program Technical Note, 24, 1–301, 1985. a
Lazarus, D., Faust, K., and Popova-Goll, I.: New species of prunoid radiolarians from the Antarctic Neogene, J. Micropaleontology, 24, 97–121, 2005. a
Lazarus, D., Suzuki, N., Caulet, J. P., Nigrini, C., Goll, I., Goll, R., Dolven, J. K., Diver, P., and Sanfilippo, A.: An evaluated list of Cenozoic-Recent radiolarian species names (Polycystinea), based on those used in the DSDP, ODP and IODP deep-sea drilling programs, Zootaxa, 3999, 301–333, 2015. a, b
Ling, H. Y. and Anikouchine, W. A.: Some spumellarian Radiolarian from the Java, Philippine, and Mariana Trenches, J. Paleon. 41, 1481–1491, 1967. a
Matsuoka, A.: Catalogue of living polycystine radiolarians in surface waters in the East China Sea around Sesoko Island, Okinawa Prefecture, Japan, Sci. Rep. Niigata Univ. (Geol.), 32, 57–90, 2017. a
Matsuzaki, K. M., Suzuki, N., Nishi, H., Hayashi, H., Gyawali, B. R., Takashima, R., and Ikehara, M.: Early to middle Pleistocene paleoceanographic history of southern Japan based on radiolarian data from IODP Exp 314/315 Sites C0001 and C0002, Mar. Micropaleontol., 118, 17–33, 2015. a
Moore, T. C.: Method of randomly distributing grains for microscopic examination, J. Sediment. Petrol., 43, 904–906, 1973. a
Moore Jr., T. J.: Radiolarian stratigraphy, Leg 138, Proc. Ocean Drill. Prog. Sci. Results, 138, 191–232, 1995. a
Motoyama, I., Yamada, Y., Hoshiba, M., and Itaki, T.: Radiolarian Assemblages in Surface Sediments of the Japan Sea, Paleontol. Res., 20, 176–206, 2016. a
Nigrini, C.: Radiolarian zones in the Quaternary of the equatorial Pacific Ocean, in: The Micropalaeontology of Oceans, edited by: Funnell, B. M. and Riedel, W. R., Cambridge University Press, Cambridge, UK, 443–461, 1971. a
Nigrini, C. and Lombari, G.: A guide to Miocene Radiolaria, Cushman Foundation Foraminiferal Research, Sp. Pub., 22, S1–S102, N1–N206, 1984. a
Nigrini, C. and Moore, T. C.: A guide to modern Radiolaria – with taxonomic descriptions and illustrations of radiolarian species, Cushman Foundation for Foraminiferal Research, Sp. Pub., Washington, USA, 16, 1979. a
Nigrini, C. and Sanfilippo, A.: Cenozoic radiolarian stratigraphy for low and middle latitudes with descriptions of biomarkers and stratigraphically useful species, ODP Tech, Note 27, available at: http://www-odp.tamu.edu/publications/tnotes/tn27/index.html (last access: 17 November 2020), 2001. a, b
Nigrini, C., Sanfilippo, A., and Moore Jr., T. J.,: Cenozoic radiolarian biostratigraphy: a magnetobiostratigraphic chronology of Cenozoic sequences from ODP Sites 1218, 1219, and 1220, equatorial Pacific, in: Proc. ODP, Sci. Results 199, edited by: Wilson, P. A., Lyle, M., and Firth, J. V., Ocean Drilling Program, College Station, TX, USA, 1–76, 2005. a
Panitz, S., Cortese, G., Neil, H. L., and Diekmann, B.: A radiolarian-based palaeoclimate history of Core Y9 (Northeast of Campbell Plateau, New Zealand) for the last 160 kyr, Mar. Micropaleontol., 116, 1–14, 2015. a
Renaudie, J., Gray, R., and Lazarus, D. B.: Accuracy of a neural net classification of closely-related species of microfossils from a sparse dataset of unedited images, PeerJ Preprints, 6, e27328v1, https://doi.org/10.7287/peerj.preprints.27328v1, 2018. a
Riedel, W. R.: Subclass Radiolaria, in: The fossil record, edited by: Harland, W. B., Holland, C. H., House, M. R., Hughes, N. F., Reynolds, A. B., Rudwick, M. J. S., Satterthwaite, G. E., Tarlo, I. B. H., and Willey, E. C., Geol. Soc., London, UK, 291–298, 1967. a
Rosenthal, Y., Holbourn, A. E., Kulhanek, D. K., and the Expedition 363 Scientists: Western Pacific Warm Pool, Proceedings of the International Ocean Discovery Program, 363: College Station, TX (International Ocean Discovery Program), 2018. a
Sandoval, M. I.: Miocene to recent radiolarians from southern pacific coast of Costa Rica, Rev. Geol. Amér. Central, 58, 115–169, 2018. a
Sanfilippo, A. and Nigrini, C.: Code numbers for Cenozoic low latitude radiolarian biostratigraphic zones and GPTS conversion tables, Mar. Micropaleontol., 33, 109–156, 1998. a
Sanfilippo, A., Westberg-Smith, M. J., and Riedel, W. R.: Cenozoic Radiolaria, in: Plankton Stratigraphy (Vol. 2): Radiolaria, Diatoms, Silicoflagellates, Dinoflagellates, and Ichthyoliths, edited by: Bolli, H. M., Saunders, J. B., and Perch-Nielsen, K., Cambridge Univ. Press, Cambridge, UK, 631–712, 1985. a, b, c, d, e
Schneider, C. A., Rasband, W. S., and Eliceiri, K. W.: NIH Image to ImageJ: 25 years of image analysis, Nat. Methods, 9, 671–675, 2012. a
Schrock, R. R. and Twenhofel, W. H.: Principles of Invertebrate Palaeontology, New second edition, McGraw Hill, New York, USA, London, UK, 816 pp., 1953. a
Sharma, V., Singh, S., and Rawal, N.: Early Middle Miocene Radiolaria from Nicobar Islands, Northeast Indian Ocean, Micropaleontology, 45, 251–277, 1999. a
Suzuki, N. and Not, F.: Biology and Ecology of Radiolaria, in: Marine Protists, edited by: Ohtsuka, S., Suzaki, T., Horiguchi, T., Suzuki, N., and Not, F., Springer, Tokyo, Japan, 2015. a
Takahashi, K.: Radiolaria: flux, ecology, and taxonomy in the Pacific and Atlantic, Woods Hole Oceanogr. Inst., Ocean Biocoenosis Ser., 3, 1–303, 1991. a
Takahashi, K. and Honjo, S.: Radiolarian skeletons: size, weight, sinking speed, and residence time in tropical pelagic oceans, Deep-Sea Res., 30, 543–568, 1983. a
Tetard, M. and Marchant, R.: AutoRadio_Segmenter, a free ImageJ plugin for image segmentation, available at: https://github.com/microfossil/ImageJ-LabView-Scripts, last access: 17 November 2020. a
Tetard, M., Marchant, R., Cortese, G., Gally, Y., de Garidel-Thoron, T., and Beaufort, L.: The AutoRadio Database, available at: http://microautomate.cerege.fr/dat, last access: 17 November 2020. a
Vigour, R. and Lazarus, D.: Biostratigraphy of late Miocene–early Pliocene radiolarians from ODP Leg 183 Site 1138, in: Proc. ODP, Sci. Results, 183, edited by: Frey, F. A., Coffin, M. F., Wallace, P. J., and Quilty, P. G., 1–17, available at: http://www-odp.tamu.edu/publications/183_SR/007/007.htm (last access: 17 November 2020), 2002. a
Welling, L. A., Pisias, N. G., and Roelofs, A. K.: Radiolarian microfauna in the northern California Current System: indicators of multiple processes controlling productivity, in: Upwelling Systems. Evolution since the Early Miocene, edited by: Summerhayes, C. P., Prell, W. L. and Emeis, K. C., London Geological Society: Geological Society Special Publication, 64, 177–195, 1992. a, b
Zhang, L. L. and Suzuki, N.: Taxonomy and species diversity of Holocene pylonioid radiolarians from surface sediments of the northeastern Indian Ocean, Palaeontol. Electron., 20.3.48A, 1–68, 2017. a
Zhang, L. L., Chen, M. H., Xiang, R., Zhang, J. L., Liu, C. J., Huang, L. M., and Lu, J.: Distribution of polycystine radiolarians in the northern South China Sea in September 2005, Mar. Micropaleontol., 70, 20–38, 2009. a
Short summary
Radiolarians are marine micro-organisms that produce a siliceous shell that is preserved in the fossil record and can be used to reconstruct past climate variability. However, their study is only possible after a time-consuming manual selection of their shells from the sediment followed by their individual identification. Thus, we develop a new fully automated workflow consisting of microscopic radiolarian image acquisition, image processing and identification using artificial intelligence.
Radiolarians are marine micro-organisms that produce a siliceous shell that is preserved in the...
