Articles | Volume 6, issue 4
https://doi.org/10.5194/gchron-6-503-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gchron-6-503-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Towards the construction of regional marine radiocarbon calibration curves: an unsupervised machine learning approach
Ana-Cristina Mârza
Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, United Kingdom
Laurie Menviel
Climate Change Research Centre, The Australian Centre for Excellence in Antarctic Science, University of New South Wales, Sydney, New South Wales, NSW 2052, Australia
Luke C. Skinner
CORRESPONDING AUTHOR
Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, United Kingdom
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Gabriel M. Pontes, Pedro Leite Silva Dias, and Laurie Menviel
EGUsphere, https://doi.org/10.5194/egusphere-2024-3062, https://doi.org/10.5194/egusphere-2024-3062, 2024
This preprint is open for discussion and under review for Climate of the Past (CP).
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El Niño events are the main driver of year-to-year tropical climate variability. Understanding how El Niño activity is affected by different climate states is of great relevance to socioeconomic, ecosystem and climate risk management. Through analysis of past and future climate simulations, we show that ENSO sensitivity to mean state changes is more complex than previously thought, exhibiting a nonlinear behavior.
Bartholomé Duboc, Katrin J. Meissner, Laurie Menviel, Nicholas K. H. Yeung, Babette Hoogakker, Tilo Ziehn, and Matthew Chamberlain
EGUsphere, https://doi.org/10.5194/egusphere-2024-2675, https://doi.org/10.5194/egusphere-2024-2675, 2024
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We use an Earth System Model to simulate ocean oxygen during two past warm periods, the Last Interglacial (~129–115 ka) and Marine Isotope Stage (MIS) 9e (~336-321 ka). The global ocean is overall less oxygenated compared to the preindustrial simulation. Large regions in the Mediterranean Sea are oxygen deprived in the Last Interglacial simulation, and to a lesser extent in the MIS 9e simulation, due to an intensification and expansion of the African Monsoon and enhanced river run-off.
Brooke Snoll, Ruza Ivanovic, Lauren Gregoire, Sam Sherriff-Tadano, Laurie Menviel, Takashi Obase, Ayako Abe-Ouchi, Nathaelle Bouttes, Chengfei He, Feng He, Marie Kapsch, Uwe Mikolajewicz, Juan Muglia, and Paul Valdes
Clim. Past, 20, 789–815, https://doi.org/10.5194/cp-20-789-2024, https://doi.org/10.5194/cp-20-789-2024, 2024
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Geological records show rapid climate change throughout the recent deglaciation. The drivers of these changes are still misunderstood but are often attributed to shifts in the Atlantic Ocean circulation from meltwater input. A cumulative effort to understand these processes prompted numerous simulations of this period. We use these to explain the chain of events and our collective ability to simulate them. The results demonstrate the importance of the meltwater amount used in the simulation.
Takashi Obase, Laurie Menviel, Ayako Abe-Ouchi, Tristan Vadsaria, Ruza Ivanovic, Brooke Snoll, Sam Sherriff-Tadano, Paul Valdes, Lauren Gregoire, Marie-Luise Kapsch, Uwe Mikolajewicz, Nathaelle Bouttes, Didier Roche, Fanny Lhardy, Chengfei He, Bette Otto-Bliesner, Zhengyu Liu, and Wing-Le Chan
Clim. Past Discuss., https://doi.org/10.5194/cp-2023-86, https://doi.org/10.5194/cp-2023-86, 2023
Revised manuscript under review for CP
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This study analyses transient simulations of the last deglaciation performed by six climate models to understand the processes driving southern high latitude temperature changes. We find that atmospheric CO2 changes and AMOC changes are the primary drivers of the major warming and cooling during the middle stage of the deglaciation. The multi-model analysis highlights the model’s sensitivity of CO2, AMOC to meltwater, and the meltwater history on temperature changes in southern high latitudes.
Laurie C. Menviel, Paul Spence, Andrew E. Kiss, Matthew A. Chamberlain, Hakase Hayashida, Matthew H. England, and Darryn Waugh
Biogeosciences, 20, 4413–4431, https://doi.org/10.5194/bg-20-4413-2023, https://doi.org/10.5194/bg-20-4413-2023, 2023
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As the ocean absorbs 25% of the anthropogenic emissions of carbon, it is important to understand the impact of climate change on the flux of carbon between the ocean and the atmosphere. Here, we use a very high-resolution ocean, sea-ice, carbon cycle model to show that the capability of the Southern Ocean to uptake CO2 has decreased over the last 40 years due to a strengthening and poleward shift of the southern hemispheric westerlies. This trend is expected to continue over the coming century.
Luke Skinner, Francois Primeau, Aurich Jeltsch-Thömmes, Fortunat Joos, Peter Köhler, and Edouard Bard
Clim. Past, 19, 2177–2202, https://doi.org/10.5194/cp-19-2177-2023, https://doi.org/10.5194/cp-19-2177-2023, 2023
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Radiocarbon is best known as a dating tool, but it also allows us to track CO2 exchange between the ocean and atmosphere. Using decades of data and novel mapping methods, we have charted the ocean’s average radiocarbon ″age” since the last Ice Age. Combined with climate model simulations, these data quantify the ocean’s role in atmospheric CO2 rise since the last Ice Age while also revealing that Earth likely received far more cosmic radiation during the last Ice Age than hitherto believed.
Himadri Saini, Katrin J. Meissner, Laurie Menviel, and Karin Kvale
Clim. Past, 19, 1559–1584, https://doi.org/10.5194/cp-19-1559-2023, https://doi.org/10.5194/cp-19-1559-2023, 2023
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Understanding the changes in atmospheric CO2 during the last glacial cycle is crucial to comprehend the impact of climate change in the future. Previous research has hypothesised a key role of greater aeolian iron input into the Southern Ocean in influencing the global atmospheric CO2 levels by impacting the changes in the marine phytoplankton response. In our study, we test this iron hypothesis using climate modelling and constrain the impact of ocean iron supply on global CO2 decrease.
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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We produced a 1.5-million-year-long history of climate change at International Ocean Discovery Program Site U1385 of the Iberian margin, a well-known location for rapidly accumulating sediments on the seafloor. Our record demonstrates that longer-term orbital changes in Earth's climate were persistently overprinted by abrupt millennial-to-centennial climate variability. The occurrence of abrupt climate change is modulated by the slower variations in Earth's orbit and climate background state.
Xavier Crosta, Karen E. Kohfeld, Helen C. Bostock, Matthew Chadwick, Alice Du Vivier, Oliver Esper, Johan Etourneau, Jacob Jones, Amy Leventer, Juliane Müller, Rachael H. Rhodes, Claire S. Allen, Pooja Ghadi, Nele Lamping, Carina B. Lange, Kelly-Anne Lawler, David Lund, Alice Marzocchi, Katrin J. Meissner, Laurie Menviel, Abhilash Nair, Molly Patterson, Jennifer Pike, Joseph G. Prebble, Christina Riesselman, Henrik Sadatzki, Louise C. Sime, Sunil K. Shukla, Lena Thöle, Maria-Elena Vorrath, Wenshen Xiao, and Jiao Yang
Clim. Past, 18, 1729–1756, https://doi.org/10.5194/cp-18-1729-2022, https://doi.org/10.5194/cp-18-1729-2022, 2022
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Despite its importance in the global climate, our knowledge of Antarctic sea-ice changes throughout the last glacial–interglacial cycle is extremely limited. As part of the Cycles of Sea Ice Dynamics in the Earth system (C-SIDE) Working Group, we review marine- and ice-core-based sea-ice proxies to provide insights into their applicability and limitations. By compiling published records, we provide information on Antarctic sea-ice dynamics over the past 130 000 years.
Ryan A. Green, Laurie Menviel, Katrin J. Meissner, Xavier Crosta, Deepak Chandan, Gerrit Lohmann, W. Richard Peltier, Xiaoxu Shi, and Jiang Zhu
Clim. Past, 18, 845–862, https://doi.org/10.5194/cp-18-845-2022, https://doi.org/10.5194/cp-18-845-2022, 2022
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Climate models are used to predict future climate changes and as such, it is important to assess their performance in simulating past climate changes. We analyze seasonal sea-ice cover over the Southern Ocean simulated from numerical PMIP3, PMIP4 and LOVECLIM simulations during the Last Glacial Maximum (LGM). Comparing these simulations to proxy data, we provide improved estimates of LGM seasonal sea-ice cover. Our estimate of summer sea-ice extent is 20 %–30 % larger than previous estimates.
Dipayan Choudhury, Laurie Menviel, Katrin J. Meissner, Nicholas K. H. Yeung, Matthew Chamberlain, and Tilo Ziehn
Clim. Past, 18, 507–523, https://doi.org/10.5194/cp-18-507-2022, https://doi.org/10.5194/cp-18-507-2022, 2022
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We investigate the effects of a warmer climate from the Earth's paleoclimate (last interglacial) on the marine carbon cycle of the Southern Ocean using a carbon-cycle-enabled state-of-the-art climate model. We find a 150 % increase in CO2 outgassing during this period, which results from competition between higher sea surface temperatures and weaker oceanic circulation. From this we unequivocally infer that the carbon uptake by the Southern Ocean will reduce under a future warming scenario.
Jun Shao, Lowell D. Stott, Laurie Menviel, Andy Ridgwell, Malin Ödalen, and Mayhar Mohtadi
Clim. Past, 17, 1507–1521, https://doi.org/10.5194/cp-17-1507-2021, https://doi.org/10.5194/cp-17-1507-2021, 2021
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Planktic and shallow benthic foraminiferal stable carbon isotope
(δ13C) data show a rapid decline during the last deglaciation. This widespread signal was linked to respired carbon released from the deep ocean and its transport through the upper-ocean circulation. Using numerical simulations in which a stronger flux of respired carbon upwells and outcrops in the Southern Ocean, we find that the depleted δ13C signal is transmitted to the rest of the upper ocean through air–sea gas exchange.
Nicholas King-Hei Yeung, Laurie Menviel, Katrin J. Meissner, Andréa S. Taschetto, Tilo Ziehn, and Matthew Chamberlain
Clim. Past, 17, 869–885, https://doi.org/10.5194/cp-17-869-2021, https://doi.org/10.5194/cp-17-869-2021, 2021
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The Last Interglacial period (LIG) is characterised by strong orbital forcing compared to the pre-industrial period (PI). This study compares the mean climate state of the LIG to the PI as simulated by the ACCESS-ESM1.5, with a focus on the southern hemispheric monsoons, which are shown to be consistently weakened. This is associated with cooler terrestrial conditions in austral summer due to decreased insolation, and greater pressure and subsidence over land from Hadley cell strengthening.
Shannon A. Bengtson, Laurie C. Menviel, Katrin J. Meissner, Lise Missiaen, Carlye D. Peterson, Lorraine E. Lisiecki, and Fortunat Joos
Clim. Past, 17, 507–528, https://doi.org/10.5194/cp-17-507-2021, https://doi.org/10.5194/cp-17-507-2021, 2021
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The last interglacial was a warm period that may provide insights into future climates. Here, we compile and analyse stable carbon isotope data from the ocean during the last interglacial and compare it to the Holocene. The data show that Atlantic Ocean circulation was similar during the last interglacial and the Holocene. We also establish a difference in the mean oceanic carbon isotopic ratio between these periods, which was most likely caused by burial and weathering carbon fluxes.
Masa Kageyama, Louise C. Sime, Marie Sicard, Maria-Vittoria Guarino, Anne de Vernal, Ruediger Stein, David Schroeder, Irene Malmierca-Vallet, Ayako Abe-Ouchi, Cecilia Bitz, Pascale Braconnot, Esther C. Brady, Jian Cao, Matthew A. Chamberlain, Danny Feltham, Chuncheng Guo, Allegra N. LeGrande, Gerrit Lohmann, Katrin J. Meissner, Laurie Menviel, Polina Morozova, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, Ryouta O'ishi, Silvana Ramos Buarque, David Salas y Melia, Sam Sherriff-Tadano, Julienne Stroeve, Xiaoxu Shi, Bo Sun, Robert A. Tomas, Evgeny Volodin, Nicholas K. H. Yeung, Qiong Zhang, Zhongshi Zhang, Weipeng Zheng, and Tilo Ziehn
Clim. Past, 17, 37–62, https://doi.org/10.5194/cp-17-37-2021, https://doi.org/10.5194/cp-17-37-2021, 2021
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The Last interglacial (ca. 127 000 years ago) is a period with increased summer insolation at high northern latitudes, resulting in a strong reduction in Arctic sea ice. The latest PMIP4-CMIP6 models all simulate this decrease, consistent with reconstructions. However, neither the models nor the reconstructions agree on the possibility of a seasonally ice-free Arctic. Work to clarify the reasons for this model divergence and the conflicting interpretations of the records will thus be needed.
Bette L. Otto-Bliesner, Esther C. Brady, Anni Zhao, Chris M. Brierley, Yarrow Axford, Emilie Capron, Aline Govin, Jeremy S. Hoffman, Elizabeth Isaacs, Masa Kageyama, Paolo Scussolini, Polychronis C. Tzedakis, Charles J. R. Williams, Eric Wolff, Ayako Abe-Ouchi, Pascale Braconnot, Silvana Ramos Buarque, Jian Cao, Anne de Vernal, Maria Vittoria Guarino, Chuncheng Guo, Allegra N. LeGrande, Gerrit Lohmann, Katrin J. Meissner, Laurie Menviel, Polina A. Morozova, Kerim H. Nisancioglu, Ryouta O'ishi, David Salas y Mélia, Xiaoxu Shi, Marie Sicard, Louise Sime, Christian Stepanek, Robert Tomas, Evgeny Volodin, Nicholas K. H. Yeung, Qiong Zhang, Zhongshi Zhang, and Weipeng Zheng
Clim. Past, 17, 63–94, https://doi.org/10.5194/cp-17-63-2021, https://doi.org/10.5194/cp-17-63-2021, 2021
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The CMIP6–PMIP4 Tier 1 lig127k experiment was designed to address the climate responses to strong orbital forcing. We present a multi-model ensemble of 17 climate models, most of which have also completed the CMIP6 DECK experiments and are thus important for assessing future projections. The lig127ksimulations show strong summer warming over the NH continents. More than half of the models simulate a retreat of the Arctic minimum summer ice edge similar to the average for 2000–2018.
Andrew H. MacDougall, Thomas L. Frölicher, Chris D. Jones, Joeri Rogelj, H. Damon Matthews, Kirsten Zickfeld, Vivek K. Arora, Noah J. Barrett, Victor Brovkin, Friedrich A. Burger, Micheal Eby, Alexey V. Eliseev, Tomohiro Hajima, Philip B. Holden, Aurich Jeltsch-Thömmes, Charles Koven, Nadine Mengis, Laurie Menviel, Martine Michou, Igor I. Mokhov, Akira Oka, Jörg Schwinger, Roland Séférian, Gary Shaffer, Andrei Sokolov, Kaoru Tachiiri, Jerry Tjiputra, Andrew Wiltshire, and Tilo Ziehn
Biogeosciences, 17, 2987–3016, https://doi.org/10.5194/bg-17-2987-2020, https://doi.org/10.5194/bg-17-2987-2020, 2020
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The Zero Emissions Commitment (ZEC) is the change in global temperature expected to occur following the complete cessation of CO2 emissions. Here we use 18 climate models to assess the value of ZEC. For our experiment we find that ZEC 50 years after emissions cease is between −0.36 to +0.29 °C. The most likely value of ZEC is assessed to be close to zero. However, substantial continued warming for decades or centuries following cessation of CO2 emission cannot be ruled out.
Laurie Menviel, Emilie Capron, Aline Govin, Andrea Dutton, Lev Tarasov, Ayako Abe-Ouchi, Russell N. Drysdale, Philip L. Gibbard, Lauren Gregoire, Feng He, Ruza F. Ivanovic, Masa Kageyama, Kenji Kawamura, Amaelle Landais, Bette L. Otto-Bliesner, Ikumi Oyabu, Polychronis C. Tzedakis, Eric Wolff, and Xu Zhang
Geosci. Model Dev., 12, 3649–3685, https://doi.org/10.5194/gmd-12-3649-2019, https://doi.org/10.5194/gmd-12-3649-2019, 2019
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As part of the Past Global Changes (PAGES) working group on Quaternary Interglacials, we propose a protocol to perform transient simulations of the penultimate deglaciation for the Paleoclimate Modelling Intercomparison Project (PMIP4). This design includes time-varying changes in orbital forcing, greenhouse gas concentrations, continental ice sheets as well as freshwater input from the disintegration of continental ice sheets. Key paleo-records for model-data comparison are also included.
Daniel P. Lowry, Nicholas R. Golledge, Laurie Menviel, and Nancy A. N. Bertler
Clim. Past, 15, 189–215, https://doi.org/10.5194/cp-15-189-2019, https://doi.org/10.5194/cp-15-189-2019, 2019
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Using two climate models, we seek to better understand changes in Antarctic climate and Southern Ocean conditions during the last deglaciation. We highlight the importance of sea ice and ice topography changes for Antarctic surface temperatures and snow accumulation as well as the sensitivity of Southern Ocean temperatures to meltwater fluxes. The results demonstrate that climate model simulations of the deglaciation could be greatly improved by considering ice–ocean interactions and feedbacks.
Laurie Menviel, Emilie Capron, Aline Govin, Andrea Dutton, Lev Tarasov, Ayako Abe-Ouchi, Russell Drysdale, Philip Gibbard, Lauren Gregoire, Feng He, Ruza Ivanovic, Masa Kageyama, Kenji Kawamura, Amaelle Landais, Bette L. Otto-Bliesner, Ikumi Oyabu, Polychronis Tzedakis, Eric Wolff, and Xu Zhang
Clim. Past Discuss., https://doi.org/10.5194/cp-2018-106, https://doi.org/10.5194/cp-2018-106, 2018
Preprint withdrawn
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The penultimate deglaciation (~ 138–128 ka), which represents the transition into the Last Interglacial period, provides a framework to investigate the climate and environmental response to large changes in boundary conditions. Here, as part of the PAGES-PMIP working group on Quaternary Interglacials, we propose a protocol to perform transient simulations of the penultimate deglaciation as well as a selection of paleo records for upcoming model-data comparisons.
L. Menviel, A. Timmermann, T. Friedrich, and M. H. England
Clim. Past, 10, 63–77, https://doi.org/10.5194/cp-10-63-2014, https://doi.org/10.5194/cp-10-63-2014, 2014
Related subject area
Radiocarbon dating
New age constraints reveal moraine stabilization thousands of years after deposition during the last deglaciation of western New York, USA
The marine reservoir age of Greenland coastal waters
Marine reservoir ages for coastal West Africa
Spatial variability of the modern radiocarbon reservoir effect in the high-altitude lake Laguna del Peinado (southern Puna Plateau, Argentina)
Short communication: Driftwood provides reliable chronological markers in Arctic coastal deposits
A new 30 000-year chronology for rapidly deposited sediments on the Lomonosov Ridge using bulk radiocarbon dating and probabilistic stratigraphic alignment
Miniature radiocarbon measurements ( < 150 µg C) from sediments of Lake Żabińskie, Poland: effect of precision and dating density on age–depth models
Re-evaluating 14C dating accuracy in deep-sea sediment archives
Karlee K. Prince, Jason P. Briner, Caleb K. Walcott, Brooke M. Chase, Andrew L. Kozlowski, Tammy M. Rittenour, and Erica P. Yang
Geochronology, 6, 409–427, https://doi.org/10.5194/gchron-6-409-2024, https://doi.org/10.5194/gchron-6-409-2024, 2024
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We fill a spatial data gap in the ice sheet retreat history of the Laurentide Ice Sheet after the Last Glacial Maximum and investigate a hypothesis that the ice sheet re-advanced into western New York, USA, at ~13 ka. With radiocarbon and optically stimulated luminescence (OSL) dating, we find that ice began retreating from its maximum extent after 20 ka, but glacial ice persisted in glacial landforms until ~15–14 ka when they finally stabilized. We find no evidence of a re-advance at ~13 ka.
Christof Pearce, Karen Søby Özdemir, Ronja Forchhammer Mathiasen, Henrieka Detlef, and Jesper Olsen
Geochronology, 5, 451–465, https://doi.org/10.5194/gchron-5-451-2023, https://doi.org/10.5194/gchron-5-451-2023, 2023
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Reliable chronologies lie at the base of paleoclimatological reconstructions. When working with marine sediment cores, the most common dating tool for recent sediments is radiocarbon, but this requires calibration to convert it to calendar ages. This calibration requires knowledge of the marine radiocarbon reservoir age, and this is known to vary in space and time. In this study we provide 92 new radiocarbon measurements to improve our knowledge of the reservoir age around Greenland.
Guillaume Soulet, Philippe Maestrati, Serge Gofas, Germain Bayon, Fabien Dewilde, Maylis Labonne, Bernard Dennielou, Franck Ferraton, and Giuseppe Siani
Geochronology, 5, 345–359, https://doi.org/10.5194/gchron-5-345-2023, https://doi.org/10.5194/gchron-5-345-2023, 2023
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The marine reservoir age (MRA) is the difference between the 14C age of the ocean and that of the atmosphere at a given time. In geochronology, knowing the local MRA is important to derive accurate calibrated ages for 14C-dated marine material. However, MRA values for coastal West Africa are scarce. From the 14C dating of known-age bivalves from museum collections, we calculated MRA values and populated the MRA dataset for coastal West Africa over a latitudinal transect from 33°N to 15°S.
Paula A. Vignoni, Francisco E. Córdoba, Rik Tjallingii, Carla Santamans, Liliana C. Lupo, and Achim Brauer
Geochronology, 5, 333–344, https://doi.org/10.5194/gchron-5-333-2023, https://doi.org/10.5194/gchron-5-333-2023, 2023
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Radiocarbon dating is a widely used tool to establish chronologies for sediment records. We show that modern aquatic plants in the Laguna del Peinado lake system (Altiplano–Puna Plateau) give overestimated ages due to reservoir effects from the input of old groundwater and volcanic CO2. Our results reveal a spatial variability in the modern reservoir effect within the lake basin, which has implications for radiocarbon-based chronologies in paleoclimate studies in this (and similar) regions.
Lasse Sander, Alexander Kirdyanov, Alan Crivellaro, and Ulf Büntgen
Geochronology, 3, 171–180, https://doi.org/10.5194/gchron-3-171-2021, https://doi.org/10.5194/gchron-3-171-2021, 2021
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Coastal deposits can help us reconstruct the timing of climate-induced changes in the rates of past landscape evolution. In this study, we show that consistent ages for Holocene beach shorelines can be obtained by dating driftwood deposits. This finding is surprising, as the wood travels long distances through river systems before reaching the Arctic Ocean. The possibility to establish precise age control is a prerequisite to further investigate the regional drivers of long-term coastal change.
Francesco Muschitiello, Matt O'Regan, Jannik Martens, Gabriel West, Örjan Gustafsson, and Martin Jakobsson
Geochronology, 2, 81–91, https://doi.org/10.5194/gchron-2-81-2020, https://doi.org/10.5194/gchron-2-81-2020, 2020
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In this study we present a new marine chronology of the last ~30 000 years for a sediment core retrieved from the central Arctic Ocean. Our new chronology reveals substantially faster sedimentation rates during the end of the last glacial cycle, the Last Glacial Maximum, and deglaciation than previously reported, thus implying a substantial re-interpretation of paleoceanographic reconstructions from this sector of the Arctic Ocean.
Paul D. Zander, Sönke Szidat, Darrell S. Kaufman, Maurycy Żarczyński, Anna I. Poraj-Górska, Petra Boltshauser-Kaltenrieder, and Martin Grosjean
Geochronology, 2, 63–79, https://doi.org/10.5194/gchron-2-63-2020, https://doi.org/10.5194/gchron-2-63-2020, 2020
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Recent technological advances allow researchers to obtain radiocarbon ages from smaller samples than previously possible. We investigate the reliability and precision of radiocarbon ages obtained from miniature (11–150 μg C) samples of terrestrial plant fragments taken from sediment cores from Lake Żabińskie, Poland. We further investigate how sampling density (the number of ages per 1000 years) and sample mass (which is related to age precision) influence the performance of age–depth models.
Bryan C. Lougheed, Philippa Ascough, Andrew M. Dolman, Ludvig Löwemark, and Brett Metcalfe
Geochronology, 2, 17–31, https://doi.org/10.5194/gchron-2-17-2020, https://doi.org/10.5194/gchron-2-17-2020, 2020
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The current geochronological state of the art for applying the radiocarbon (14C) method to deep-sea sediment archives lacks key information on sediment bioturbation, which could affect palaeoclimate interpretations made from deep-sea sediment. We use a computer model that simulates the 14C activity and bioturbation history of millions of single foraminifera at the sea floor, allowing us to evaluate the current state of the art at the most fundamental level.
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Short summary
Radiocarbon serves as a powerful dating tool, but the calibration of marine radiocarbon dates presents significant challenges because the whole surface ocean cannot be represented by a single calibration curve. Here we use climate model outputs and data to assess a novel method for developing regional marine calibration curves. Our results are encouraging and point to a way forward for solving the marine radiocarbon age calibration problem without relying on model simulations of the past.
Radiocarbon serves as a powerful dating tool, but the calibration of marine radiocarbon dates...