Articles | Volume 21, issue 6
https://doi.org/10.5194/os-21-3311-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-21-3311-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Dec 2025
Research article |
| 04 Dec 2025
| 04 Dec 2025
Changes in water mass composition and circulation in the central Arctic Ocean between 2011 and 2021 inferred from tracer observations
Anne-Marie Wefing
CORRESPONDING AUTHOR
Department of Environmental Systems Science, ETHZ, Zurich, Switzerland
Norwegian Polar Institute, Tromsø, Norway
Annabel Payne
Department of Environmental Systems Science, ETHZ, Zurich, Switzerland
Marcel Scheiwiller
Department of Environmental Systems Science, ETHZ, Zurich, Switzerland
Christof Vockenhuber
Department of Environmental Systems Science, ETHZ, Zurich, Switzerland
Laboratory of Ion Beam Physics, ETHZ, Zurich, Switzerland
Marcus Christl
Laboratory of Ion Beam Physics, ETHZ, Zurich, Switzerland
Toste Tanhua
GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
Núria Casacuberta
Department of Environmental Systems Science, ETHZ, Zurich, Switzerland
Laboratory of Ion Beam Physics, ETHZ, Zurich, Switzerland
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William A. Nesbitt, Alfonso O. Mucci, Toste Tanhua, Yves Gélinas, Jean-Éric Tremblay, Gwénaëlle Chaillou, Ludovic Pascal, Caroline Fradette, Lennart Gerke, Samuel W. Stevens, Mathilde Jutras, Marjolaine Blais, Martine Lizotte, Michel Starr, and Douglas W. R. Wallace
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-7, https://doi.org/10.5194/essd-2026-7, 2026
Preprint under review for ESSD
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Over the past few decades, the St. Lawrence Estuary and Gulf have shown clear trends in oxygen depletion and acidification. This data description paper brings together twenty years of measurements from the St. Lawrence Estuary, Gulf of St. Lawrence, and Saguenay Fjord, carefully performing quality control procedures on data, and makes them publicly available. The resulting dataset supports future research, monitoring, and environmental management in this sensitive marine system.
Chantal Schmidt, David Mair, Naki Akçar, Marcus Christl, Negar Haghipour, Christof Vockenhuber, Philip Gautschi, Brian McArdell, and Fritz Schlunegger
Earth Surf. Dynam., 14, 33–53, https://doi.org/10.5194/esurf-14-33-2026, https://doi.org/10.5194/esurf-14-33-2026, 2026
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Our study examines erosion in a small, pre-Alpine basin by using cosmogenic nuclides in river sediments. Based on a dense measuring network we were able to distinguish two main zones: an upper zone with slow erosion of surface material, and a steeper, lower zone where faster erosion is driven by landslides. The data suggests that sediment has been constantly produced over thousands of years, indicating a stable, long-term balance between contrasting erosion processes.
Angus Moore, Maud Henrion, Yanfei Li, Eléonore du bois d'Aische, Philip Gautschi, Marcus Christl, François Jonard, Sébastien Lambot, Kristof Van Oost, Sophie Opfergelt, and Veerle Vanacker
EGUsphere, https://doi.org/10.5194/egusphere-2026-36, https://doi.org/10.5194/egusphere-2026-36, 2026
This preprint is open for discussion and under review for Earth Surface Dynamics (ESurf).
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Studying peatlands dynamics over long timescales requires a proxy for past peat cover. In this paper, we explore the use of cosmogenic nuclides to infer peat thicknesses averaged over 100 kyr timescales. We find that long-term peat thicknesses inferred from cosmogenic nuclides at an upland peatland site in the Belgian Ardennes are consistent with independent constraints, but exceed modern peat thicknesses. We attribute this discrepancy to peat degradation associated with historical land use.
Marta Álvarez, Maribel I. García-Ibáñez, Nico Lange, Alex Kozyr, Antón Velo, Toste Tanhua, Giuseppe Civitarese, Carolina Cantoni, Malek Belgacem, Katrin Schroeder, Rubén Acerbi, Laurent Coppola, Thibaut Wagener, Noelia M. Fajar, Susana Flecha, Michele Giani, Louisa Giannoudi, Elisa F. Guallart, Abed El Rahman Hassoun, Emma I. Huertas, Valeria Ibello, Mehdia A. Keraghel, Ferial Louanchi, Anna Luchetta, Fiz F. Pérez, Carsten Schirnick, Ekaterini Souvermezoglou, Lidia Urbini, Monserrat Vidal, and Patrizia Ziveri
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-759, https://doi.org/10.5194/essd-2025-759, 2025
Preprint under review for ESSD
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CARIMED (CARbon, tracers, and ancillary data In the MEDiterranean Sea) is a high-quality, FAIR dataset integrating hydrographic, biogeochemical, and transient tracer data from 46 research cruises (1976–2018) across the Mediterranean Sea. The data underwent rigorous, basin-adapted quality control to remove systematic biases, unifying four decades of fragmented data, delivering two complementary products: the aggregated original cruise data product and the bias-adjusted data synthesis product.
Lukas Rettig, Sandro Rossato, Sarah Kamleitner, Paolo Mozzi, Susan Ivy-Ochs, Enrico Marcato, Marcus Christl, Silvana Martin, and Giovanni Monegato
E&G Quaternary Sci. J., 74, 151–168, https://doi.org/10.5194/egqsj-74-151-2025, https://doi.org/10.5194/egqsj-74-151-2025, 2025
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The work shows detailed reconstructions of the glaciers in the Valsugana area (south-eastern Alps) during the Last Glacial Maximum (LGM) and is supported by robust evidence and new exposure datings. These are the first ages for the internal sector of the south-eastern Alps. Local glaciers not connected with the major ice network were used for the calculation of their equilibrium line altitude. This let us estimate LGM palaeoprecipitation and compare it to Alpine palaeoclimatological models.
William A. Nesbitt, Samuel W. Stevens, Alfonso O. Mucci, Lennart Gerke, Toste Tanhua, Gwénaëlle Chaillou, and Douglas W. R. Wallace
Ocean Sci., 21, 2179–2195, https://doi.org/10.5194/os-21-2179-2025, https://doi.org/10.5194/os-21-2179-2025, 2025
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We combine two decades of oxygen data with new carbon observations and a tracer-informed model to quantify oxygen loss and carbon buildup in the deep waters of the Gulf and Lower St. Lawrence Estuary. We then test a novel idea: reoxygenating these waters with the oxygen produced as a by-product from green-hydrogen production. Our results suggest this could significantly reduce hypoxia, though full recovery would require larger inputs.
Niklas Kappelt, Eric Wolff, Marcus Christl, Christof Vockenhuber, Philip Gautschi, and Raimund Muscheler
Clim. Past, 21, 1585–1594, https://doi.org/10.5194/cp-21-1585-2025, https://doi.org/10.5194/cp-21-1585-2025, 2025
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By measuring the radioactive decay of atmospherically produced 36Cl and 10Be in an ice core drilled in West Antarctica, we were able to determine the age of the deepest sample close to bedrock to be about 550 thousand years old. This means that the ice in this location, known as Skytrain Ice Rise, has survived several warm periods in the past, at least since marine isotope stage 11.
Lisa G. T. Leist, Maxi Castrillejo, Kumiko Azetsu-Scott, Craig Lee, Jed Lenetsky, Marc Ringuette, Christof Vockenhuber, Habacuc Pérez-Tribouilier, and Núria Casacuberta
EGUsphere, https://doi.org/10.5194/egusphere-2025-4178, https://doi.org/10.5194/egusphere-2025-4178, 2025
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The Arctic and Atlantic Oceans are connected by narrow passages, and the exchange of waters affect global climate. Using artificial radionuclides from nuclear reprocessing discharges, we traced the origin of water masses from the Arctic to the Labrador Sea. Results show that waters from Canadian Arctic origin entering via Lancaster Sound are a key freshwater source to the Labrador Sea. These flows strongly influence the formation of deep waters in the Atlantic, vital for the global circulation.
Lennart Gerke, Toste Tanhua, William A. Nesbitt, Samuel W. Stevens, and Douglas W. R. Wallace
EGUsphere, https://doi.org/10.5194/egusphere-2025-3999, https://doi.org/10.5194/egusphere-2025-3999, 2025
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Transient tracer data, measured for the first time in 2022 in the Gulf of St. Lawrence, reveal older deep waters in the east than the west, contrary to expected estuarine circulation, indicating increased influence of older, warmer, less oxygenated North Atlantic Central Water over younger, oxygen-rich Labrador Current Water. While consistent with previous reports of increasing NACW contribution, our results contradict claims of a complete shift to NACW by 2021, showing that LCW still persists.
Li-Qing Jiang, Amanda Fay, Jens Daniel Müller, Lydia Keppler, Dustin Carroll, Siv K. Lauvset, Tim DeVries, Judith Hauck, Christian Rödenbeck, Luke Gregor, Nicolas Metzl, Andrea J. Fassbender, Jean-Pierre Gattuso, Peter Landschützer, Rik Wanninkhof, Christopher Sabine, Simone R. Alin, Mario Hoppema, Are Olsen, Matthew P. Humphreys, Kumiko Azetsu-Scott, Dorothee C. E. Bakker, Leticia Barbero, Nicholas R. Bates, Nicole Besemer, Henry C. Bittig, Albert E. Boyd, Daniel Broullón, Wei-Jun Cai, Brendan R. Carter, Thi-Tuyet-Trang Chau, Chen-Tung Arthur Chen, Frédéric Cyr, John E. Dore, Ian Enochs, Richard A. Feely, Hernan E. Garcia, Marion Gehlen, Lucas Gloege, Melchor González-Dávila, Nicolas Gruber, Yosuke Iida, Masao Ishii, Esther Kennedy, Alex Kozyr, Nico Lange, Claire Lo Monaco, Derek P. Manzello, Galen A. McKinley, Natalie M. Monacci, Xose A. Padin, Ana M. Palacio-Castro, Fiz F. Pérez, Alizée Roobaert, J. Magdalena Santana-Casiano, Jonathan Sharp, Adrienne Sutton, Jim Swift, Toste Tanhua, Maciej Telszewski, Jens Terhaar, Ruben van Hooidonk, Anton Velo, Andrew J. Watson, Angelicque E. White, Zelun Wu, Hyelim Yoo, and Jiye Zeng
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-255, https://doi.org/10.5194/essd-2025-255, 2025
Revised manuscript accepted for ESSD
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This review article provides an overview of 60 existing ocean carbonate chemistry data products, encompassing a broad range of types, including compilations of cruise datasets, gap-filled observational products, model simulations, and more. It is designed to help researchers identify and access the data products that best support their scientific objectives, thereby facilitating progress in understanding the ocean's changing carbonate chemistry.
Janet C. Richardson, Veerle Vanacker, David M. Hodgson, Marcus Christl, and Andreas Lang
Earth Surf. Dynam., 13, 315–339, https://doi.org/10.5194/esurf-13-315-2025, https://doi.org/10.5194/esurf-13-315-2025, 2025
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Pediments are long flat surfaces that extend outwards from the foot of mountains; within South Africa they are regarded as ancient landforms that can give key insights into landscape and mantle dynamics. Cosmogenic nuclide dating has been incorporated with geological (soil formation) and geomorphological (river incision) evidence, which shows that the pediments are long-lived features beyond the ages reported by cosmogenic nuclide dating.
Mian Liu and Toste Tanhua
EGUsphere, https://doi.org/10.5194/egusphere-2024-1362, https://doi.org/10.5194/egusphere-2024-1362, 2024
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Quantifies Atlantic water mass ages using CFC-12, SF₆, and ³⁹Ar tracers. Reveals ventilation timescales: surface (~100y mean), intermediate (AAIW ~300y), deep (NADW ~600y), bottom (NEABW ~800y). Shows younger ages in western basins due to better ventilation. Provides framework for biogeochemical studies.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 16, 2047–2072, https://doi.org/10.5194/essd-16-2047-2024, https://doi.org/10.5194/essd-16-2047-2024, 2024
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2023 is the fifth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1108 hydrographic cruises covering the world's oceans from 1972 to 2021.
Nico Lange, Björn Fiedler, Marta Álvarez, Alice Benoit-Cattin, Heather Benway, Pier Luigi Buttigieg, Laurent Coppola, Kim Currie, Susana Flecha, Dana S. Gerlach, Makio Honda, I. Emma Huertas, Siv K. Lauvset, Frank Muller-Karger, Arne Körtzinger, Kevin M. O'Brien, Sólveig R. Ólafsdóttir, Fernando C. Pacheco, Digna Rueda-Roa, Ingunn Skjelvan, Masahide Wakita, Angelicque White, and Toste Tanhua
Earth Syst. Sci. Data, 16, 1901–1931, https://doi.org/10.5194/essd-16-1901-2024, https://doi.org/10.5194/essd-16-1901-2024, 2024
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The Synthesis Product for Ocean Time Series (SPOTS) is a novel achievement expanding and complementing the biogeochemical data landscape by providing consistent and high-quality biogeochemical time-series data from 12 ship-based fixed time-series programs. SPOTS covers multiple unique marine environments and time-series ranges, including data from 1983 to 2021. All in all, it facilitates a variety of applications that benefit from the collective value of biogeochemical time-series observations.
Chiara I. Paleari, Florian Mekhaldi, Tobias Erhardt, Minjie Zheng, Marcus Christl, Florian Adolphi, Maria Hörhold, and Raimund Muscheler
Clim. Past, 19, 2409–2422, https://doi.org/10.5194/cp-19-2409-2023, https://doi.org/10.5194/cp-19-2409-2023, 2023
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In this study, we test the use of excess meltwater from continuous flow analysis from a firn core from Greenland for the measurement of 10Be for solar activity reconstructions. We show that the quality of results is similar to the measurements on clean firn, which opens the possibility to obtain continuous 10Be records without requiring large amounts of clean ice. Furthermore, we investigate the possibility of identifying solar storm signals in 10Be records from Greenland and Antarctica.
Catharina Dieleman, Philip Deline, Susan Ivy Ochs, Patricia Hug, Jordan Aaron, Marcus Christl, and Naki Akçar
EGUsphere, https://doi.org/10.5194/egusphere-2023-1873, https://doi.org/10.5194/egusphere-2023-1873, 2023
Preprint withdrawn
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Valleys in the Alps are shaped by glaciers, rivers, mass movements, and slope processes. An understanding of such processes is of great importance in hazard mitigation. We focused on the evolution of the Frébouge cone, which is composed of glacial, debris flow, rock avalanche, and snow avalanche deposits. Debris flows started to form the cone prior to ca. 2 ka ago. In addition, the cone was overrun by a 10 Mm3 large rock avalanche at 1.3 ± 0.1 ka and by the Frébouge glacier at 300 ± 40 a.
Giulia Sinnl, Florian Adolphi, Marcus Christl, Kees C. Welten, Thomas Woodruff, Marc Caffee, Anders Svensson, Raimund Muscheler, and Sune Olander Rasmussen
Clim. Past, 19, 1153–1175, https://doi.org/10.5194/cp-19-1153-2023, https://doi.org/10.5194/cp-19-1153-2023, 2023
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The record of past climate is preserved by several archives from different regions, such as ice cores from Greenland or Antarctica or speleothems from caves such as the Hulu Cave in China. In this study, these archives are aligned by taking advantage of the globally synchronous production of cosmogenic radionuclides. This produces a new perspective on the global climate in the period between 20 000 and 25 000 years ago.
Robert Mulvaney, Eric W. Wolff, Mackenzie M. Grieman, Helene H. Hoffmann, Jack D. Humby, Christoph Nehrbass-Ahles, Rachael H. Rhodes, Isobel F. Rowell, Frédéric Parrenin, Loïc Schmidely, Hubertus Fischer, Thomas F. Stocker, Marcus Christl, Raimund Muscheler, Amaelle Landais, and Frédéric Prié
Clim. Past, 19, 851–864, https://doi.org/10.5194/cp-19-851-2023, https://doi.org/10.5194/cp-19-851-2023, 2023
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We present an age scale for a new ice core drilled at Skytrain Ice Rise, an ice rise facing the Ronne Ice Shelf in Antarctica. Various measurements in the ice and air phases are used to match the ice core to other Antarctic cores that have already been dated, and a new age scale is constructed. The 651 m ice core includes ice that is confidently dated to 117 000–126 000 years ago, in the last interglacial. Older ice is found deeper down, but there are flow disturbances in the deeper ice.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Simone Alin, Marta Álvarez, Kumiko Azetsu-Scott, Leticia Barbero, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Li-Qing Jiang, Steve D. Jones, Claire Lo Monaco, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 14, 5543–5572, https://doi.org/10.5194/essd-14-5543-2022, https://doi.org/10.5194/essd-14-5543-2022, 2022
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2022 is the fourth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1085 hydrographic cruises covering the world's oceans from 1972 to 2021.
Nathan Vandermaelen, Koen Beerten, François Clapuyt, Marcus Christl, and Veerle Vanacker
Geochronology, 4, 713–730, https://doi.org/10.5194/gchron-4-713-2022, https://doi.org/10.5194/gchron-4-713-2022, 2022
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We constrained deposition phases of fluvial sediments (NE Belgium) over the last 1 Myr with analysis and modelling of rare isotopes accumulation within sediments, occurring as a function of time and inverse function of depth. They allowed the determination of three superposed deposition phases and intercalated non-deposition periods of ~ 40 kyr each. These phases correspond to 20 % of the sediment age, which highlights the importance of considering deposition phase when dating fluvial sediments.
Pierre Friedlingstein, Michael O'Sullivan, Matthew W. Jones, Robbie M. Andrew, Luke Gregor, Judith Hauck, Corinne Le Quéré, Ingrid T. Luijkx, Are Olsen, Glen P. Peters, Wouter Peters, Julia Pongratz, Clemens Schwingshackl, Stephen Sitch, Josep G. Canadell, Philippe Ciais, Robert B. Jackson, Simone R. Alin, Ramdane Alkama, Almut Arneth, Vivek K. Arora, Nicholas R. Bates, Meike Becker, Nicolas Bellouin, Henry C. Bittig, Laurent Bopp, Frédéric Chevallier, Louise P. Chini, Margot Cronin, Wiley Evans, Stefanie Falk, Richard A. Feely, Thomas Gasser, Marion Gehlen, Thanos Gkritzalis, Lucas Gloege, Giacomo Grassi, Nicolas Gruber, Özgür Gürses, Ian Harris, Matthew Hefner, Richard A. Houghton, George C. Hurtt, Yosuke Iida, Tatiana Ilyina, Atul K. Jain, Annika Jersild, Koji Kadono, Etsushi Kato, Daniel Kennedy, Kees Klein Goldewijk, Jürgen Knauer, Jan Ivar Korsbakken, Peter Landschützer, Nathalie Lefèvre, Keith Lindsay, Junjie Liu, Zhu Liu, Gregg Marland, Nicolas Mayot, Matthew J. McGrath, Nicolas Metzl, Natalie M. Monacci, David R. Munro, Shin-Ichiro Nakaoka, Yosuke Niwa, Kevin O'Brien, Tsuneo Ono, Paul I. Palmer, Naiqing Pan, Denis Pierrot, Katie Pocock, Benjamin Poulter, Laure Resplandy, Eddy Robertson, Christian Rödenbeck, Carmen Rodriguez, Thais M. Rosan, Jörg Schwinger, Roland Séférian, Jamie D. Shutler, Ingunn Skjelvan, Tobias Steinhoff, Qing Sun, Adrienne J. Sutton, Colm Sweeney, Shintaro Takao, Toste Tanhua, Pieter P. Tans, Xiangjun Tian, Hanqin Tian, Bronte Tilbrook, Hiroyuki Tsujino, Francesco Tubiello, Guido R. van der Werf, Anthony P. Walker, Rik Wanninkhof, Chris Whitehead, Anna Willstrand Wranne, Rebecca Wright, Wenping Yuan, Chao Yue, Xu Yue, Sönke Zaehle, Jiye Zeng, and Bo Zheng
Earth Syst. Sci. Data, 14, 4811–4900, https://doi.org/10.5194/essd-14-4811-2022, https://doi.org/10.5194/essd-14-4811-2022, 2022
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The Global Carbon Budget 2022 describes the datasets and methodology used to quantify the anthropogenic emissions of carbon dioxide (CO2) and their partitioning among the atmosphere, the land ecosystems, and the ocean. These living datasets are updated every year to provide the highest transparency and traceability in the reporting of CO2, the key driver of climate change.
Rainer Kiko, Marc Picheral, David Antoine, Marcel Babin, Léo Berline, Tristan Biard, Emmanuel Boss, Peter Brandt, Francois Carlotti, Svenja Christiansen, Laurent Coppola, Leandro de la Cruz, Emilie Diamond-Riquier, Xavier Durrieu de Madron, Amanda Elineau, Gabriel Gorsky, Lionel Guidi, Helena Hauss, Jean-Olivier Irisson, Lee Karp-Boss, Johannes Karstensen, Dong-gyun Kim, Rachel M. Lekanoff, Fabien Lombard, Rubens M. Lopes, Claudie Marec, Andrew M. P. McDonnell, Daniela Niemeyer, Margaux Noyon, Stephanie H. O'Daly, Mark D. Ohman, Jessica L. Pretty, Andreas Rogge, Sarah Searson, Masashi Shibata, Yuji Tanaka, Toste Tanhua, Jan Taucher, Emilia Trudnowska, Jessica S. Turner, Anya Waite, and Lars Stemmann
Earth Syst. Sci. Data, 14, 4315–4337, https://doi.org/10.5194/essd-14-4315-2022, https://doi.org/10.5194/essd-14-4315-2022, 2022
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The term
marine particlescomprises detrital aggregates; fecal pellets; bacterioplankton, phytoplankton and zooplankton; and even fish. Here, we present a global dataset that contains 8805 vertical particle size distribution profiles obtained with Underwater Vision Profiler 5 (UVP5) camera systems. These data are valuable to the scientific community, as they can be used to constrain important biogeochemical processes in the ocean, such as the flux of carbon to the deep sea.
Joanne Elkadi, Benjamin Lehmann, Georgina E. King, Olivia Steinemann, Susan Ivy-Ochs, Marcus Christl, and Frédéric Herman
Earth Surf. Dynam., 10, 909–928, https://doi.org/10.5194/esurf-10-909-2022, https://doi.org/10.5194/esurf-10-909-2022, 2022
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Glacial and non-glacial processes have left a strong imprint on the landscape of the European Alps, but further research is needed to better understand their long-term effects. We apply a new technique combining two methods for bedrock surface dating to calculate post-glacier erosion rates next to a Swiss glacier. Interestingly, the results suggest non-glacial erosion rates are higher than previously thought, but glacial erosion remains the most influential on landscape evolution.
Elena Serra, Pierre G. Valla, Romain Delunel, Natacha Gribenski, Marcus Christl, and Naki Akçar
Earth Surf. Dynam., 10, 493–512, https://doi.org/10.5194/esurf-10-493-2022, https://doi.org/10.5194/esurf-10-493-2022, 2022
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Alpine landscapes are transformed by several erosion processes. 10Be concentrations measured in river sediments at the outlet of a basin represent a powerful tool to quantify how fast the catchment erodes. We measured erosion rates within the Dora Baltea catchments (western Italian Alps). Our results show that erosion is governed by topography, bedrock resistance and glacial imprint. The Mont Blanc massif has the highest erosion and therefore dominates the sediment flux of the Dora Baltea river.
Pierre Friedlingstein, Matthew W. Jones, Michael O'Sullivan, Robbie M. Andrew, Dorothee C. E. Bakker, Judith Hauck, Corinne Le Quéré, Glen P. Peters, Wouter Peters, Julia Pongratz, Stephen Sitch, Josep G. Canadell, Philippe Ciais, Rob B. Jackson, Simone R. Alin, Peter Anthoni, Nicholas R. Bates, Meike Becker, Nicolas Bellouin, Laurent Bopp, Thi Tuyet Trang Chau, Frédéric Chevallier, Louise P. Chini, Margot Cronin, Kim I. Currie, Bertrand Decharme, Laique M. Djeutchouang, Xinyu Dou, Wiley Evans, Richard A. Feely, Liang Feng, Thomas Gasser, Dennis Gilfillan, Thanos Gkritzalis, Giacomo Grassi, Luke Gregor, Nicolas Gruber, Özgür Gürses, Ian Harris, Richard A. Houghton, George C. Hurtt, Yosuke Iida, Tatiana Ilyina, Ingrid T. Luijkx, Atul Jain, Steve D. Jones, Etsushi Kato, Daniel Kennedy, Kees Klein Goldewijk, Jürgen Knauer, Jan Ivar Korsbakken, Arne Körtzinger, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Sebastian Lienert, Junjie Liu, Gregg Marland, Patrick C. McGuire, Joe R. Melton, David R. Munro, Julia E. M. S. Nabel, Shin-Ichiro Nakaoka, Yosuke Niwa, Tsuneo Ono, Denis Pierrot, Benjamin Poulter, Gregor Rehder, Laure Resplandy, Eddy Robertson, Christian Rödenbeck, Thais M. Rosan, Jörg Schwinger, Clemens Schwingshackl, Roland Séférian, Adrienne J. Sutton, Colm Sweeney, Toste Tanhua, Pieter P. Tans, Hanqin Tian, Bronte Tilbrook, Francesco Tubiello, Guido R. van der Werf, Nicolas Vuichard, Chisato Wada, Rik Wanninkhof, Andrew J. Watson, David Willis, Andrew J. Wiltshire, Wenping Yuan, Chao Yue, Xu Yue, Sönke Zaehle, and Jiye Zeng
Earth Syst. Sci. Data, 14, 1917–2005, https://doi.org/10.5194/essd-14-1917-2022, https://doi.org/10.5194/essd-14-1917-2022, 2022
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The Global Carbon Budget 2021 describes the data sets and methodology used to quantify the emissions of carbon dioxide and their partitioning among the atmosphere, land, and ocean. These living data are updated every year to provide the highest transparency and traceability in the reporting of CO2, the key driver of climate change.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Steven van Heuven, Mario Hoppema, Masao Ishii, Emil Jeansson, Sara Jutterström, Steve D. Jones, Maren K. Karlsen, Claire Lo Monaco, Patrick Michaelis, Akihiko Murata, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Anton Velo, Rik Wanninkhof, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 13, 5565–5589, https://doi.org/10.5194/essd-13-5565-2021, https://doi.org/10.5194/essd-13-5565-2021, 2021
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2021 is the third update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality control, including systematic evaluation of measurement biases. This version contains data from 989 hydrographic cruises covering the world's oceans from 1972 to 2020.
Gerd Krahmann, Damian L. Arévalo-Martínez, Andrew W. Dale, Marcus Dengler, Anja Engel, Nicolaas Glock, Patricia Grasse, Johannes Hahn, Helena Hauss, Mark Hopwood, Rainer Kiko, Alexandra Loginova, Carolin R. Löscher, Marie Maßmig, Alexandra-Sophie Roy, Renato Salvatteci, Stefan Sommer, Toste Tanhua, and Hela Mehrtens
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2020-308, https://doi.org/10.5194/essd-2020-308, 2021
Preprint withdrawn
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The project "Climate-Biogeochemistry Interactions in the Tropical Ocean" (SFB 754) was a multidisciplinary research project active from 2008 to 2019 aimed at a better understanding of the coupling between the tropical climate and ocean circulation and the ocean's oxygen and nutrient balance. On 34 research cruises, mainly in the Southeast Tropical Pacific and the Northeast Tropical Atlantic, 1071 physical, chemical and biological data sets were collected.
Pingyang Li and Toste Tanhua
Ocean Sci., 17, 509–525, https://doi.org/10.5194/os-17-509-2021, https://doi.org/10.5194/os-17-509-2021, 2021
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Observations of transient tracer distribution provide essential information on ocean ventilation. The use of several commonly used transient traces is limited as their atmospheric mole fractions do not monotonically change. Here we explore new potential oceanic transient tracers with an analytical system that simultaneously measures a large range of compounds. Combined with the known atmospheric history and seawater solubility, we discuss the utility of selected HCFCs, HFCs, and PFCs as tracers.
Mian Liu and Toste Tanhua
Ocean Sci., 17, 463–486, https://doi.org/10.5194/os-17-463-2021, https://doi.org/10.5194/os-17-463-2021, 2021
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We have characterized the major water masses in the Atlantic Ocean based on the properties found in their formation areas using six properties taken from the GLODAPv2 data product, including both conservative (conservative temperature and absolute salinity) and non-conservative (oxygen, silicate, phosphate and nitrate) properties. The distributions of the water masses are estimated by using the optimum multi-parameter (OMP) model, and we have mapped the distributions of the water masses.
Cited articles
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Short summary
Here we used the anthropogenic radionuclides I-129 and U-236 as tracers for Atlantic Water circulation in the Arctic Ocean. New data collected in 2021 allowed to assess the distribution of Atlantic Water and mixing with Pacific-origin water in the surface layer in that year. By using historical tracer data from 2011 to 2021, we looked into temporal changes of the circulation and found slightly older waters in the central Arctic Ocean in 2021 compared to 2015.
Here we used the anthropogenic radionuclides I-129 and U-236 as tracers for Atlantic Water...
