Articles | Volume 18, issue 11
https://doi.org/10.5194/cp-18-2509-2022
© Author(s) 2022. 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-18-2509-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Nov 2022
Research article |
| 22 Nov 2022
| 22 Nov 2022
Accurately calibrated X-ray fluorescence core scanning (XRF-CS) record of Ti ∕ Al reveals Early Pleistocene aridity and humidity variability over North Africa and its close relationship to low-latitude insolation
Rick Hennekam
CORRESPONDING AUTHOR
Department of Ocean Systems, NIOZ Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Den Burg, Texel, the Netherlands
Katharine M. Grant
Research School of Earth Sciences, Australian National University,
Canberra, ACT 2600, Australia
Eelco J. Rohling
Research School of Earth Sciences, Australian National University,
Canberra, ACT 2600, Australia
Ocean and Earth Science, National
Oceanography Centre, University of Southampton, Southampton, SO14 3ZH, UK
Rik Tjallingii
GFZ German Research Centre for Geosciences, Sect. 5.2 – Climate
Dynamics and Landscape Evolution, 14473 Potsdam, Germany
David Heslop
Research School of Earth Sciences, Australian National University,
Canberra, ACT 2600, Australia
Andrew P. Roberts
Research School of Earth Sciences, Australian National University,
Canberra, ACT 2600, Australia
Lucas J. Lourens
Department of Earth Sciences, Faculty of Geosciences, Utrecht
University, P.O. Box 80.121, 3508 TA Utrecht, the Netherlands
Gert-Jan Reichart
Department of Ocean Systems, NIOZ Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Den Burg, Texel, the Netherlands
Department of Earth Sciences, Faculty of Geosciences, Utrecht
University, P.O. Box 80.121, 3508 TA Utrecht, the Netherlands
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Charlotte Eich, Mathijs van Manen, J. Scott P. McCain, Loay J. Jabre, Willem H. van de Poll, Jinyoung Jung, Sven B. E. H. Pont, Hung-An Tian, Indah Ardiningsih, Gert-Jan Reichart, Erin M. Bertrand, Corina P. D. Brussaard, and Rob Middag
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Joost Frieling, Linda van Roij, Iris Kleij, Gert-Jan Reichart, and Appy Sluijs
Biogeosciences, 20, 4651–4668, https://doi.org/10.5194/bg-20-4651-2023, https://doi.org/10.5194/bg-20-4651-2023, 2023
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David A. Hodell, Simon J. Crowhurst, Lucas Lourens, Vasiliki Margari, John Nicolson, James E. Rolfe, Luke C. Skinner, Nicola C. Thomas, Polychronis C. Tzedakis, Maryline J. Mleneck-Vautravers, and Eric W. Wolff
Clim. Past, 19, 607–636, https://doi.org/10.5194/cp-19-607-2023, https://doi.org/10.5194/cp-19-607-2023, 2023
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Markus Czymzik, Rik Tjallingii, Birgit Plessen, Peter Feldens, Martin Theuerkauf, Matthias Moros, Markus J. Schwab, Carla K. M. Nantke, Silvia Pinkerneil, Achim Brauer, and Helge W. Arz
Clim. Past, 19, 233–248, https://doi.org/10.5194/cp-19-233-2023, https://doi.org/10.5194/cp-19-233-2023, 2023
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Productivity increases in Lake Kälksjön sediments during the last 9600 years are likely driven by the progressive millennial-scale winter warming in northwestern Europe, following the increasing Northern Hemisphere winter insolation and decadal to centennial periods of a more positive NAO polarity. Strengthened productivity variability since ∼5450 cal yr BP is hypothesized to reflect a reinforcement of NAO-like atmospheric circulation.
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.
Clara T. Bolton, Emmeline Gray, Wolfgang Kuhnt, Ann E. Holbourn, Julia Lübbers, Katharine Grant, Kazuyo Tachikawa, Gianluca Marino, Eelco J. Rohling, Anta-Clarisse Sarr, and Nils Andersen
Clim. Past, 18, 713–738, https://doi.org/10.5194/cp-18-713-2022, https://doi.org/10.5194/cp-18-713-2022, 2022
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The timing of the initiation and evolution of the South Asian monsoon in the geological past is a subject of debate. Here, we present a new age model spanning the late Miocene (9 to 5 million years ago) and high-resolution records of past open-ocean biological productivity from the equatorial Indian Ocean that we interpret to reflect monsoon wind strength. Our data show no long-term intensification; however, strong orbital periodicities suggest insolation forcing of monsoon wind strength.
Henry Hooghiemstra, Gustavo Sarmiento Pérez, Vladimir Torres Torres, Juan-Carlos Berrío, Lucas Lourens, and Suzette G. A. Flantua
Sci. Dril., 30, 1–15, https://doi.org/10.5194/sd-30-1-2022, https://doi.org/10.5194/sd-30-1-2022, 2022
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This is a brief overview of long continental fossil pollen records globally in relationship with marine records. Specifically, the Northern Andes is a key area in developing and testing hypotheses in the fields of ecology, paleobiogeography, and climate change in tropical regions. We review 60 years of deep drilling experience in this region that have led to landmark records. We also highlight the early development of long continental pollen records from unique, deep, sediment-filled basins.
Alice E. Webb, Didier M. de Bakker, Karline Soetaert, Tamara da Costa, Steven M. A. C. van Heuven, Fleur C. van Duyl, Gert-Jan Reichart, and Lennart J. de Nooijer
Biogeosciences, 18, 6501–6516, https://doi.org/10.5194/bg-18-6501-2021, https://doi.org/10.5194/bg-18-6501-2021, 2021
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The biogeochemical behaviour of shallow reef communities is quantified to better understand the impact of habitat degradation and species composition shifts on reef functioning. The reef communities investigated barely support reef functions that are usually ascribed to conventional coral reefs, and the overall biogeochemical behaviour is found to be similar regardless of substrate type. This suggests a decrease in functional diversity which may therefore limit services provided by this reef.
Anna Joy Drury, Diederik Liebrand, Thomas Westerhold, Helen M. Beddow, David A. Hodell, Nina Rohlfs, Roy H. Wilkens, Mitchell Lyle, David B. Bell, Dick Kroon, Heiko Pälike, and Lucas J. Lourens
Clim. Past, 17, 2091–2117, https://doi.org/10.5194/cp-17-2091-2021, https://doi.org/10.5194/cp-17-2091-2021, 2021
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We use the first high-resolution southeast Atlantic carbonate record to see how climate dynamics evolved since 30 million years ago (Ma). During ~ 30–13 Ma, eccentricity (orbital circularity) paced carbonate deposition. After the mid-Miocene Climate Transition (~ 14 Ma), precession (Earth's tilt direction) increasingly drove carbonate variability. In the latest Miocene (~ 8 Ma), obliquity (Earth's tilt) pacing appeared, signalling increasing high-latitude influence.
Indah Ardiningsih, Kyyas Seyitmuhammedov, Sylvia G. Sander, Claudine H. Stirling, Gert-Jan Reichart, Kevin R. Arrigo, Loes J. A. Gerringa, and Rob Middag
Biogeosciences, 18, 4587–4601, https://doi.org/10.5194/bg-18-4587-2021, https://doi.org/10.5194/bg-18-4587-2021, 2021
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Organic Fe speciation is investigated along a natural gradient of the western Antarctic Peninsula from an ice-covered shelf to the open ocean. The two major fronts in the region affect the distribution of ligands. The excess ligands not bound to dissolved Fe (DFe) comprised up to 80 % of the total ligand concentrations, implying the potential to solubilize additional Fe input. The ligands on the shelf can increase the DFe residence time and fuel local primary production upon ice melt.
Cécile L. Blanchet, Rik Tjallingii, Anja M. Schleicher, Stefan Schouten, Martin Frank, and Achim Brauer
Clim. Past, 17, 1025–1050, https://doi.org/10.5194/cp-17-1025-2021, https://doi.org/10.5194/cp-17-1025-2021, 2021
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The Mediterranean Sea turned repeatedly into an oxygen-deprived basin during the geological past, as evidenced by distinct sediment layers called sapropels. We use here records of the last sapropel S1 retrieved in front of the Nile River to explore the relationships between riverine input and seawater oxygenation. We decipher the seasonal cycle of fluvial input and seawater chemistry as well as the decisive influence of primary productivity on deoxygenation at millennial timescales.
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Short summary
The ratio of titanium to aluminum (Ti/Al) is an established way to reconstruct North African climate in eastern Mediterranean Sea sediments. We demonstrate here how to obtain reliable Ti/Al data using an efficient scanning method that allows rapid acquisition of long climate records at low expense. Using this method, we reconstruct a 3-million-year North African climate record. African environmental variability was paced predominantly by low-latitude insolation from 3–1.2 million years ago.
The ratio of titanium to aluminum (Ti/Al) is an established way to reconstruct North African...
