Articles | Volume 14, issue 9
https://doi.org/10.5194/cp-14-1315-2018
© Author(s) 2018. 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-14-1315-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Sep 2018
Research article |
| 18 Sep 2018
| 18 Sep 2018
Relative timing of precipitation and ocean circulation changes in the western equatorial Atlantic over the last 45 kyr
Claire Waelbroeck
CORRESPONDING AUTHOR
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Sylvain Pichat
Laboratoire de Géologie de Lyon (LGL-TPE), Ecole Normale
Supérieure de Lyon, Université de Lyon, CNRS UMR5276, 69007 Lyon,
France
Climate Geochemistry Department, Max Planck Institute for
Chemistry, Mainz, Germany
Evelyn Böhm
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Bryan C. Lougheed
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Davide Faranda
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Mathieu Vrac
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Lise Missiaen
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Natalia Vazquez Riveiros
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Ifremer, Unité de Geosciences Marines, 29280 Plouzané,
France
Pierre Burckel
IPGP, Université Sorbonne, 75238 Paris, France
Jörg Lippold
Institute of Earth Sciences, Heidelberg University, Im Neuenheimer
Feld 234, 69120 Heidelberg, Germany
Helge W. Arz
Leibniz-Institute for Baltic Sea Research Warnemünde,
Seestrasse 15, 18119 Rostock, Germany
Trond Dokken
Uni Research and Bjreknes Centre for Climate Research,
Nygårdsgaten 112, 5008 Bergen, Norway
François Thil
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
Arnaud Dapoigny
LSCE/IPSL, Laboratoire CNRS-CEA-UVSQ, 91198 Gif-sur-Yvette,
France
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Robin Noyelle, Davide Faranda, Yoann Robin, Mathieu Vrac, and Pascal Yiou
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Duncan Pappert, Alexandre Tuel, Dim Coumou, Mathieu Vrac, and Olivia Martius
Weather Clim. Dynam., 6, 769–788, https://doi.org/10.5194/wcd-6-769-2025, https://doi.org/10.5194/wcd-6-769-2025, 2025
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Germain Bénard, Marion Gehlen, and Mathieu Vrac
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We introduce a novel approach to compare Earth system model output using a causality-based approach. The analysis of interactions between atmospheric, oceanic and biogeochemical variables in the North Atlantic subpolar gyre highlights the dynamics of each model. This method reveals potential underlying causes of model differences, offering a tool for enhanced model evaluation and improved understanding of complex Earth system dynamics under past and future climates.
Louise Abot, Aurélien Quiquet, and Claire Waelbroeck
Clim. Past, 21, 1123–1142, https://doi.org/10.5194/cp-21-1123-2025, https://doi.org/10.5194/cp-21-1123-2025, 2025
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This modeling study examines how the Northern Hemisphere ice sheets interact with oceans during the last glacial period. Amplified melting beneath the ice shelves results in increased freshwater release, cooling the Northern Hemisphere and slowing ocean circulation. Freshwater release and localized ocean cooling dampen ice discharges, showing complex feedback at the interface. This study emphasizes the need for additional modeling studies to clarify the role of the ocean in past abrupt events.
Werner Ehrmann, Paul A. Wilson, Helge W. Arz, and Gerhard Schmiedl
Clim. Past, 21, 1025–1041, https://doi.org/10.5194/cp-21-1025-2025, https://doi.org/10.5194/cp-21-1025-2025, 2025
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We report palaeoclimate and sediment provenance records for the last 220 kyr from a sediment core from the northern Red Sea. They comprise high-resolution grain size, clay mineral, and geochemical data, together with Nd and Sr isotope data. The data sets document a strong temporal variability in dust influx on glacial–interglacial timescales and several shorter-term strong fluvial episodes. A key finding is that the Nile delta became a major dust source during glacioeustatic sea-level lowstands.
Isabell Hochfeld, Ben A. Ward, Anke Kremp, Juliane Romahn, Alexandra Schmidt, Miklós Bálint, Lutz Becks, Jérôme Kaiser, Helge W. Arz, Sarah Bolius, Laura S. Epp, Markus Pfenninger, Christopher A. Klausmeier, Elena Litchman, and Jana Hinners
Biogeosciences, 22, 2363–2380, https://doi.org/10.5194/bg-22-2363-2025, https://doi.org/10.5194/bg-22-2363-2025, 2025
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Marine ecosystem models (MEMs) are valuable for assessing the threats of global warming to biodiversity and ecosystem functioning, but their predictions vary widely. We argue that MEMs should consider evolutionary processes and undergo independent validation. Here, we present a novel framework for MEM development using validation data from sediment archives, which map long-term environmental and evolutionary change. Our approach is a crucial step towards improving the predictive power of MEMs.
Clémence Paul, Clément Piel, Joana Sauze, Olivier Jossoud, Arnaud Dapoigny, Daniele Romanini, Frédéric Prié, Sébastien Devidal, Roxanne Jacob, Alexandru Milcu, and Amaëlle Landais
Geosci. Instrum. Method. Data Syst., 14, 91–101, https://doi.org/10.5194/gi-14-91-2025, https://doi.org/10.5194/gi-14-91-2025, 2025
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Our study investigated the influence of plant processes on oxygen dynamics, crucial for paleoclimatology. By examining maize respiration and photosynthesis using advanced techniques, we enhanced our understanding of past climates through ice core analysis.
Gilles Reverdin, Claire Waelbroeck, Antje H. L. Voelker, and Hanno Meyer
Ocean Sci., 21, 567–575, https://doi.org/10.5194/os-21-567-2025, https://doi.org/10.5194/os-21-567-2025, 2025
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Water isotopes in the ocean trace the freshwater exchanges between the ocean, the atmosphere, and the cryosphere and are used to investigate processes of the hydrological cycle. We illustrate offsets in seawater isotopic composition between different datasets that are larger than the expected variability that one often wants to explore. This highlights the need to share seawater isotopic composition samples dedicated to specific intercomparison of data produced in different laboratories.
Ferran Lopez-Marti, Mireia Ginesta, Davide Faranda, Anna Rutgersson, Pascal Yiou, Lichuan Wu, and Gabriele Messori
Earth Syst. Dynam., 16, 169–187, https://doi.org/10.5194/esd-16-169-2025, https://doi.org/10.5194/esd-16-169-2025, 2025
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Explosive cyclones and atmospheric rivers are two main drivers of extreme weather in Europe. In this study, we investigate their joint changes in future climates over the North Atlantic. Our results show that both the concurrence of these events and the intensity of atmospheric rivers increase by the end of the century across different future scenarios. Furthermore, explosive cyclones associated with atmospheric rivers last longer and are deeper than those without atmospheric rivers.
José A. Jiménez, Gundula Winter, Antonio Bonaduce, Michael Depuydt, Giulia Galluccio, Bart van den Hurk, H. E. Markus Meier, Nadia Pinardi, Lavinia G. Pomarico, and Natalia Vazquez Riveiros
State Planet, 3-slre1, 3, https://doi.org/10.5194/sp-3-slre1-3-2024, https://doi.org/10.5194/sp-3-slre1-3-2024, 2024
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The Knowledge Hub on Sea Level Rise (SLR) has done a scoping study involving stakeholders from government and academia to identify gaps and needs in SLR information, impacts, and policies across Europe. Gaps in regional SLR projections and uncertainties were found, while concerns were raised about shoreline erosion and emerging problems like saltwater intrusion and ineffective adaptation plans. The need for improved communication to make better decisions on SLR adaptation was highlighted.
Davide Faranda, Gabriele Messori, Erika Coppola, Tommaso Alberti, Mathieu Vrac, Flavio Pons, Pascal Yiou, Marion Saint Lu, Andreia N. S. Hisi, Patrick Brockmann, Stavros Dafis, Gianmarco Mengaldo, and Robert Vautard
Weather Clim. Dynam., 5, 959–983, https://doi.org/10.5194/wcd-5-959-2024, https://doi.org/10.5194/wcd-5-959-2024, 2024
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We introduce ClimaMeter, a tool offering real-time insights into extreme-weather events. Our tool unveils how climate change and natural variability affect these events, affecting communities worldwide. Our research equips policymakers and the public with essential knowledge, fostering informed decisions and enhancing climate resilience. We analysed two distinct events, showcasing ClimaMeter's global relevance.
Loïc Martin, Julius Nouet, Arnaud Dapoigny, Gaëlle Barbotin, Fanny Claverie, Edwige Pons-Branchu, Jocelyn Barbarand, Christophe Pécheyran, Norbert Mercier, Fanny Derym, Bernard Gély, and Hélène Valladas
Geochronology, 6, 247–263, https://doi.org/10.5194/gchron-6-247-2024, https://doi.org/10.5194/gchron-6-247-2024, 2024
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Carbonate wall deposits of Trou du Renard cave (France) were dated using a multimethod approach: U–Th dating by bulk dissolution of samples and inductively coupled plasma mass spectrometry (ICP-MS), U–Th dating by laser ablation ICP-MS imaging, and radiocarbon dating. The samples were studied to ensure that they give reliable ages. Ages ranging from 187.9 ± 5.3 ka and 1.4 ± 0.1 ka were found. This approach should make it possible to establish more robust chronologies of archaeological caves.
Mathieu Vrac, Denis Allard, Grégoire Mariéthoz, Soulivanh Thao, and Lucas Schmutz
Earth Syst. Dynam., 15, 735–762, https://doi.org/10.5194/esd-15-735-2024, https://doi.org/10.5194/esd-15-735-2024, 2024
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We aim to combine multiple global climate models (GCMs) to enhance the robustness of future projections. We introduce a novel approach, called "α pooling", aggregating the cumulative distribution functions (CDFs) of the models into a CDF more aligned with historical data. The new CDFs allow us to perform bias adjustment of all the raw climate simulations at once. Experiments with European temperature and precipitation demonstrate the superiority of this approach over conventional techniques.
Moctar Dembélé, Mathieu Vrac, Natalie Ceperley, Sander J. Zwart, Josh Larsen, Simon J. Dadson, Grégoire Mariéthoz, and Bettina Schaefli
Proc. IAHS, 385, 121–127, https://doi.org/10.5194/piahs-385-121-2024, https://doi.org/10.5194/piahs-385-121-2024, 2024
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This study assesses the impact of climate change on the timing, seasonality and magnitude of mean annual minimum (MAM) flows and annual maximum flows (AMF) in the Volta River basin (VRB). Several climate change projection data are use to simulate river flow under multiple greenhouse gas emission scenarios. Future projections show that AMF could increase with various magnitude but negligible shift in time across the VRB, while MAM could decrease with up to 14 days of delay in occurrence.
Lucas Fery and Davide Faranda
Weather Clim. Dynam., 5, 439–461, https://doi.org/10.5194/wcd-5-439-2024, https://doi.org/10.5194/wcd-5-439-2024, 2024
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In this study, we analyse warm-season derechos – a type of severe convective windstorm – in France between 2000 and 2022, identifying 38 events. We compare their frequency and features with other countries. We also examine changes in the associated large-scale patterns. We find that convective instability has increased in southern Europe. However, the attribution of these changes to natural climate variability, human-induced climate change or a combination of both remains unclear.
Raphaël Hubert-Huard, Nils Andersen, Helge W. Arz, Werner Ehrmann, and Gerhard Schmiedl
Clim. Past, 20, 267–280, https://doi.org/10.5194/cp-20-267-2024, https://doi.org/10.5194/cp-20-267-2024, 2024
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We have studied the geochemistry of benthic foraminifera (micro-fossils) from a sediment core from the Red Sea. Our data show that the circulation and carbon cycling of the Red Sea during the last glacial period responded to high-latitude millennial-scale climate variability and to the orbital influence of the African–Indian monsoon system. This implies a sensitive response of the Red Sea to climate changes.
Werner Ehrmann, Paul A. Wilson, Helge W. Arz, Hartmut Schulz, and Gerhard Schmiedl
Clim. Past, 20, 37–52, https://doi.org/10.5194/cp-20-37-2024, https://doi.org/10.5194/cp-20-37-2024, 2024
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Climatic and associated hydrological changes controlled the aeolian versus fluvial transport processes and the composition of the sediments in the central Red Sea through the last ca. 200 kyr. We identify source areas of the mineral dust and pulses of fluvial discharge based on high-resolution grain size, clay mineral, and geochemical data, together with Nd and Sr isotope data. We provide a detailed reconstruction of changes in aridity/humidity.
Julia Rieke Hagemann, Lester Lembke-Jene, Frank Lamy, Maria-Elena Vorrath, Jérôme Kaiser, Juliane Müller, Helge W. Arz, Jens Hefter, Andrea Jaeschke, Nicoletta Ruggieri, and Ralf Tiedemann
Clim. Past, 19, 1825–1845, https://doi.org/10.5194/cp-19-1825-2023, https://doi.org/10.5194/cp-19-1825-2023, 2023
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Alkenones and glycerol dialkyl glycerol tetraether lipids (GDGTs) are common biomarkers for past water temperatures. In high latitudes, determining temperature reliably is challenging. We analyzed 33 Southern Ocean sediment surface samples and evaluated widely used global calibrations for both biomarkers. For GDGT-based temperatures, previously used calibrations best reflect temperatures >5° C; (sub)polar temperature bias necessitates a new calibration which better aligns with modern values.
Emma Holmberg, Gabriele Messori, Rodrigo Caballero, and Davide Faranda
Earth Syst. Dynam., 14, 737–765, https://doi.org/10.5194/esd-14-737-2023, https://doi.org/10.5194/esd-14-737-2023, 2023
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We analyse the duration of large-scale patterns of air movement in the atmosphere, referred to as persistence, and whether unusually persistent patterns favour warm-temperature extremes in Europe. We see no clear relationship between summertime heatwaves and unusually persistent patterns. This suggests that heatwaves do not necessarily require the continued flow of warm air over a region and that local effects could be important for their occurrence.
Claire Waelbroeck, Jerry Tjiputra, Chuncheng Guo, Kerim H. Nisancioglu, Eystein Jansen, Natalia Vázquez Riveiros, Samuel Toucanne, Frédérique Eynaud, Linda Rossignol, Fabien Dewilde, Elodie Marchès, Susana Lebreiro, and Silvia Nave
Clim. Past, 19, 901–913, https://doi.org/10.5194/cp-19-901-2023, https://doi.org/10.5194/cp-19-901-2023, 2023
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The precise geometry and extent of Atlantic circulation changes that accompanied rapid climate changes of the last glacial period are still unknown. Here, we combine carbon isotopic records from 18 Atlantic sediment cores with numerical simulations and decompose the carbon isotopic change across a cold-to-warm transition into remineralization and circulation components. Our results show that the replacement of southern-sourced by northern-sourced water plays a dominant role below ~ 3000 m depth.
Cedric Gacial Ngoungue Langue, Christophe Lavaysse, Mathieu Vrac, and Cyrille Flamant
Nat. Hazards Earth Syst. Sci., 23, 1313–1333, https://doi.org/10.5194/nhess-23-1313-2023, https://doi.org/10.5194/nhess-23-1313-2023, 2023
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Heat waves (HWs) are climatic hazards that affect the planet. We assess here uncertainties encountered in the process of HW detection and analyse their recent trends in West Africa using reanalysis data. Three types of uncertainty have been investigated. We identified 6 years with higher frequency of HWs, possibly due to higher sea surface temperatures in the equatorial Atlantic. We noticed an increase in HW characteristics during the last decade, which could be a consequence of climate change.
Clémence Paul, Clément Piel, Joana Sauze, Nicolas Pasquier, Frédéric Prié, Sébastien Devidal, Roxanne Jacob, Arnaud Dapoigny, Olivier Jossoud, Alexandru Milcu, and Amaëlle Landais
Biogeosciences, 20, 1047–1062, https://doi.org/10.5194/bg-20-1047-2023, https://doi.org/10.5194/bg-20-1047-2023, 2023
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To improve the interpretation of the δ18Oatm and Δ17O of O2 in air bubbles in ice cores, we need to better quantify the oxygen fractionation coefficients associated with biological processes. We performed a simplified analogue of the terrestrial biosphere in a closed chamber. We found a respiration fractionation in agreement with the previous estimates at the microorganism scale, and a terrestrial photosynthetic fractionation was found. This has an impact on the estimation of the Dole effect.
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.
Bastien François and Mathieu Vrac
Nat. Hazards Earth Syst. Sci., 23, 21–44, https://doi.org/10.5194/nhess-23-21-2023, https://doi.org/10.5194/nhess-23-21-2023, 2023
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Compound events (CEs) result from a combination of several climate phenomena. In this study, we propose a new methodology to assess the time of emergence of CE probabilities and to quantify the contribution of marginal and dependence properties of climate phenomena to the overall CE probability changes. By applying our methodology to two case studies, we show the importance of considering changes in both marginal and dependence properties for future risk assessments related to CEs.
Davide Faranda, Stella Bourdin, Mireia Ginesta, Meriem Krouma, Robin Noyelle, Flavio Pons, Pascal Yiou, and Gabriele Messori
Weather Clim. Dynam., 3, 1311–1340, https://doi.org/10.5194/wcd-3-1311-2022, https://doi.org/10.5194/wcd-3-1311-2022, 2022
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We analyze the atmospheric circulation leading to impactful extreme events for the calendar year 2021 such as the Storm Filomena, Westphalia floods, Hurricane Ida and Medicane Apollo. For some of the events, we find that climate change has contributed to their occurrence or enhanced their intensity; for other events, we find that they are unprecedented. Our approach underscores the importance of considering changes in the atmospheric circulation when performing attribution studies.
Wout Krijgsman, Iuliana Vasiliev, Anouk Beniest, Timothy Lyons, Johanna Lofi, Gabor Tari, Caroline P. Slomp, Namik Cagatay, Maria Triantaphyllou, Rachel Flecker, Dan Palcu, Cecilia McHugh, Helge Arz, Pierre Henry, Karen Lloyd, Gunay Cifci, Özgür Sipahioglu, Dimitris Sakellariou, and the BlackGate workshop participants
Sci. Dril., 31, 93–110, https://doi.org/10.5194/sd-31-93-2022, https://doi.org/10.5194/sd-31-93-2022, 2022
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BlackGate seeks to MSP drill a transect to study the impact of dramatic hydrologic change in Mediterranean–Black Sea connectivity by recovering the Messinian to Holocene (~ 7 Myr) sedimentary sequence in the North Aegean, Marmara, and Black seas. These archives will reveal hydrographic, biotic, and climatic transitions studied by a broad scientific community spanning the stratigraphic, tectonic, biogeochemical, and microbiological evolution of Earth’s most recent saline and anoxic giant.
Antoine Grisart, Mathieu Casado, Vasileios Gkinis, Bo Vinther, Philippe Naveau, Mathieu Vrac, Thomas Laepple, Bénédicte Minster, Frederic Prié, Barbara Stenni, Elise Fourré, Hans Christian Steen-Larsen, Jean Jouzel, Martin Werner, Katy Pol, Valérie Masson-Delmotte, Maria Hoerhold, Trevor Popp, and Amaelle Landais
Clim. Past, 18, 2289–2301, https://doi.org/10.5194/cp-18-2289-2022, https://doi.org/10.5194/cp-18-2289-2022, 2022
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This paper presents a compilation of high-resolution (11 cm) water isotopic records, including published and new measurements, for the last 800 000 years from the EPICA Dome C ice core, Antarctica. Using this new combined water isotopes (δ18O and δD) dataset, we study the variability and possible influence of diffusion at the multi-decadal to multi-centennial scale. We observe a stronger variability at the onset of the interglacial interval corresponding to a warm period.
Flavio Maria Emanuele Pons and Davide Faranda
Adv. Stat. Clim. Meteorol. Oceanogr., 8, 155–186, https://doi.org/10.5194/ascmo-8-155-2022, https://doi.org/10.5194/ascmo-8-155-2022, 2022
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The objective motivating this study is the assessment of the impacts of winter climate extremes, which requires accurate simulation of snowfall. However, climate simulation models contain physical approximations, which result in biases that must be corrected using past data as a reference. We show how to exploit simulated temperature and precipitation to estimate snowfall from already bias-corrected variables, without requiring the elaboration of complex, multivariate bias adjustment techniques.
Gilles Reverdin, Claire Waelbroeck, Catherine Pierre, Camille Akhoudas, Giovanni Aloisi, Marion Benetti, Bernard Bourlès, Magnus Danielsen, Jérôme Demange, Denis Diverrès, Jean-Claude Gascard, Marie-Noëlle Houssais, Hervé Le Goff, Pascale Lherminier, Claire Lo Monaco, Herlé Mercier, Nicolas Metzl, Simon Morisset, Aïcha Naamar, Thierry Reynaud, Jean-Baptiste Sallée, Virginie Thierry, Susan E. Hartman, Edward W. Mawji, Solveig Olafsdottir, Torsten Kanzow, Anton Velo, Antje Voelker, Igor Yashayaev, F. Alexander Haumann, Melanie J. Leng, Carol Arrowsmith, and Michael Meredith
Earth Syst. Sci. Data, 14, 2721–2735, https://doi.org/10.5194/essd-14-2721-2022, https://doi.org/10.5194/essd-14-2721-2022, 2022
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The CISE-LOCEAN seawater stable isotope dataset has close to 8000 data entries. The δ18O and δD isotopic data measured at LOCEAN have uncertainties of at most 0.05 ‰ and 0.25 ‰, respectively. Some data were adjusted to correct for evaporation. The internal consistency indicates that the data can be used to investigate time and space variability to within 0.03 ‰ and 0.15 ‰ in δ18O–δD17; comparisons with data analyzed in other institutions suggest larger differences with other datasets.
Miriam D'Errico, Flavio Pons, Pascal Yiou, Soulivanh Tao, Cesare Nardini, Frank Lunkeit, and Davide Faranda
Earth Syst. Dynam., 13, 961–992, https://doi.org/10.5194/esd-13-961-2022, https://doi.org/10.5194/esd-13-961-2022, 2022
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Climate change is already affecting weather extremes. In a warming climate, we will expect the cold spells to decrease in frequency and intensity. Our analysis shows that the frequency of circulation patterns leading to snowy cold-spell events over Italy will not decrease under business-as-usual emission scenarios, although the associated events may not lead to cold conditions in the warmer scenarios.
Moctar Dembélé, Mathieu Vrac, Natalie Ceperley, Sander J. Zwart, Josh Larsen, Simon J. Dadson, Grégoire Mariéthoz, and Bettina Schaefli
Hydrol. Earth Syst. Sci., 26, 1481–1506, https://doi.org/10.5194/hess-26-1481-2022, https://doi.org/10.5194/hess-26-1481-2022, 2022
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Climate change impacts on water resources in the Volta River basin are investigated under various global warming scenarios. Results reveal contrasting changes in future hydrological processes and water availability, depending on greenhouse gas emission scenarios, with implications for floods and drought occurrence over the 21st century. These findings provide insights for the elaboration of regional adaptation and mitigation strategies for climate change.
Bryan C. Lougheed and Brett Metcalfe
Biogeosciences, 19, 1195–1209, https://doi.org/10.5194/bg-19-1195-2022, https://doi.org/10.5194/bg-19-1195-2022, 2022
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Measurements on sea-dwelling shelled organisms called foraminifera retrieved from deep-sea sediment cores have been used to reconstruct sea surface temperature (SST) variation. To evaluate the method, we use a computer model to simulate millions of single foraminifera and how they become mixed in the sediment after being deposited on the seafloor. We compare the SST inferred from the single foraminifera in the sediment core to the true SST in the water, thus quantifying method uncertainties.
Bérengère Dubrulle, François Daviaud, Davide Faranda, Louis Marié, and Brice Saint-Michel
Nonlin. Processes Geophys., 29, 17–35, https://doi.org/10.5194/npg-29-17-2022, https://doi.org/10.5194/npg-29-17-2022, 2022
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Present climate models discuss climate change but show no sign of bifurcation in the future. Is this because there is none or because they are in essence too simplified to be able to capture them? To get elements of an answer, we ran a laboratory experiment and discovered that the answer is not so simple.
María H. Toyos, Gisela Winckler, Helge W. Arz, Lester Lembke-Jene, Carina B. Lange, Gerhard Kuhn, and Frank Lamy
Clim. Past, 18, 147–166, https://doi.org/10.5194/cp-18-147-2022, https://doi.org/10.5194/cp-18-147-2022, 2022
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Past export production in the southeast Pacific and its link to Patagonian ice dynamics is unknown. We reconstruct biological productivity changes at the Pacific entrance to the Drake Passage, covering the past 400 000 years. We show that glacial–interglacial variability in export production responds to glaciogenic Fe supply from Patagonia and silica availability due to shifts in oceanic fronts, whereas dust, as a source of lithogenic material, plays a minor role.
Yoann Robin and Mathieu Vrac
Earth Syst. Dynam., 12, 1253–1273, https://doi.org/10.5194/esd-12-1253-2021, https://doi.org/10.5194/esd-12-1253-2021, 2021
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We propose a new multivariate downscaling and bias correction approach called
time-shifted multivariate bias correction, which aims to correct temporal dependencies in addition to inter-variable and spatial ones. Our method is evaluated in a
perfect model experimentcontext where simulations are used as pseudo-observations. The results show a large reduction of the biases in the temporal properties, while inter-variable and spatial dependence structures are still correctly adjusted.
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Short summary
Recording the precise timing and sequence of events is essential for understanding rapid climate changes and improving climate model predictive skills. Here, we precisely assess the relative timing between ocean and atmospheric changes, both recorded in the same deep-sea core over the last 45 kyr. We show that decreased mid-depth water mass transport in the western equatorial Atlantic preceded increased rainfall over the adjacent continent by 120 to 980 yr, depending on the type of climate event.
Recording the precise timing and sequence of events is essential for understanding rapid climate...
