Articles | Volume 14, issue 4
https://doi.org/10.5194/esd-14-733-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/esd-14-733-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
ESD Ideas: A 6-year oscillation in the whole Earth system?
Anny Cazenave
CORRESPONDING AUTHOR
Laboratoire d'Etudes en Géophysique et Océanographie Spatiales,
Toulouse, 31400 France
Magellium, Ramonville St Agne, 31520 France
Julia Pfeffer
Magellium, Ramonville St Agne, 31520 France
Mioara Mandea
Centre National d'Etudes Spatiales, Paris, 75039 Cedex 01 France
Veronique Dehant
Royal Observatory of Belgium, Brussels, B1180 Belgium
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Marie Bouih, Anne Barnoud, Chunxue Yang, Andrea Storto, Alejandro Blazquez, William Llovel, Robin Fraudeau, and Anny Cazenave
Ocean Sci., 21, 1425–1440, https://doi.org/10.5194/os-21-1425-2025, https://doi.org/10.5194/os-21-1425-2025, 2025
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Present-day sea level rise is not uniform regionally. For better understanding of regional sea level variations, a classical approach is to compare the observed sea level trend patterns with those of the sum of the contributions. If the regional sea level trend budget is not closed, this allows the detection of errors in the observing systems. Our study shows that the trend budget is not closed in the North Atlantic Ocean and identifies errors in Argo-based salinity data as the main suspect.
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The GRACE (Gravity Recovery And Climate Experiment) satellite mission enabled the quantification of water mass redistributions from 2002 to 2017. The analysis of GRACE satellite data shows here that slow changes in terrestrial water storage occurring over a few years to a decade are severely underestimated by global hydrological models. Several sources of errors may explain such biases, likely including the inaccurate representation of groundwater storage changes.
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The increase in ocean mass due to land ice melting is responsible for about two-thirds of the global mean sea level rise. The ocean mass variations are monitored by GRACE and GRACE Follow-On gravimetry satellites that faced instrumental issues over the last few years. In this work, we assess the robustness of these data by comparing the ocean mass gravimetry estimates to independent observations (other satellite observations, oceanographic measurements and land ice and water models).
Martin Horwath, Benjamin D. Gutknecht, Anny Cazenave, Hindumathi Kulaiappan Palanisamy, Florence Marti, Ben Marzeion, Frank Paul, Raymond Le Bris, Anna E. Hogg, Inès Otosaka, Andrew Shepherd, Petra Döll, Denise Cáceres, Hannes Müller Schmied, Johnny A. Johannessen, Jan Even Øie Nilsen, Roshin P. Raj, René Forsberg, Louise Sandberg Sørensen, Valentina R. Barletta, Sebastian B. Simonsen, Per Knudsen, Ole Baltazar Andersen, Heidi Ranndal, Stine K. Rose, Christopher J. Merchant, Claire R. Macintosh, Karina von Schuckmann, Kristin Novotny, Andreas Groh, Marco Restano, and Jérôme Benveniste
Earth Syst. Sci. Data, 14, 411–447, https://doi.org/10.5194/essd-14-411-2022, https://doi.org/10.5194/essd-14-411-2022, 2022
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Global mean sea-level change observed from 1993 to 2016 (mean rate of 3.05 mm yr−1) matches the combined effect of changes in water density (thermal expansion) and ocean mass. Ocean-mass change has been assessed through the contributions from glaciers, ice sheets, and land water storage or directly from satellite data since 2003. Our budget assessments of linear trends and monthly anomalies utilise new datasets and uncertainty characterisations developed within ESA's Climate Change Initiative.
Yvan Gouzenes, Fabien Léger, Anny Cazenave, Florence Birol, Pascal Bonnefond, Marcello Passaro, Fernando Nino, Rafael Almar, Olivier Laurain, Christian Schwatke, Jean-François Legeais, and Jérôme Benveniste
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This study provides for the first time estimates of sea level anomalies very close to the coastline based on high-resolution retracked altimetry data, as well as corresponding sea level trends, over a 14-year time span. This new information has so far not been provided by standard altimetry data.
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This preprint is open for discussion and under review for Solid Earth (SE).
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By analyzing 45 years of Very Long Baseline Interferometry data, we found that the liquid outer core and solid mantle are more strongly coupled than expected, likely due to topography at their boundary. The solid inner core is also less rigidly connected to the outer core. These results challenge current models of Earth's deep interior, core dynamics, and magnetic field generation, with implications for geophysics and space navigation.
Marie Bouih, Anne Barnoud, Chunxue Yang, Andrea Storto, Alejandro Blazquez, William Llovel, Robin Fraudeau, and Anny Cazenave
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Present-day sea level rise is not uniform regionally. For better understanding of regional sea level variations, a classical approach is to compare the observed sea level trend patterns with those of the sum of the contributions. If the regional sea level trend budget is not closed, this allows the detection of errors in the observing systems. Our study shows that the trend budget is not closed in the North Atlantic Ocean and identifies errors in Argo-based salinity data as the main suspect.
Andrea Storto, Giulia Chierici, Julia Pfeffer, Anne Barnoud, Romain Bourdalle-Badie, Alejandro Blazquez, Davide Cavaliere, Noémie Lalau, Benjamin Coupry, Marie Drevillon, Sebastien Fourest, Gilles Larnicol, and Chunxue Yang
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Anita Thea Saraswati, Olivier de Viron, and Mioara Mandea
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Julia Pfeffer, Anny Cazenave, Alejandro Blazquez, Bertrand Decharme, Simon Munier, and Anne Barnoud
Hydrol. Earth Syst. Sci., 27, 3743–3768, https://doi.org/10.5194/hess-27-3743-2023, https://doi.org/10.5194/hess-27-3743-2023, 2023
Short summary
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Ocean Sci., 19, 321–334, https://doi.org/10.5194/os-19-321-2023, https://doi.org/10.5194/os-19-321-2023, 2023
Short summary
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The increase in ocean mass due to land ice melting is responsible for about two-thirds of the global mean sea level rise. The ocean mass variations are monitored by GRACE and GRACE Follow-On gravimetry satellites that faced instrumental issues over the last few years. In this work, we assess the robustness of these data by comparing the ocean mass gravimetry estimates to independent observations (other satellite observations, oceanographic measurements and land ice and water models).
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Short summary
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Global mean sea-level change observed from 1993 to 2016 (mean rate of 3.05 mm yr−1) matches the combined effect of changes in water density (thermal expansion) and ocean mass. Ocean-mass change has been assessed through the contributions from glaciers, ice sheets, and land water storage or directly from satellite data since 2003. Our budget assessments of linear trends and monthly anomalies utilise new datasets and uncertainty characterisations developed within ESA's Climate Change Initiative.
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The Earth energy imbalance at the top of the atmosphere due to the increase in greenhouse gases and aerosol concentrations is responsible for the accumulation of energy in the climate system. With its high thermal inertia, the ocean accumulates most of this energy excess in the form of heat. The estimation of the global ocean heat content through space geodetic observations allows monitoring of the energy imbalance with realistic uncertainties to better understand the Earth’s warming climate.
Yvan Gouzenes, Fabien Léger, Anny Cazenave, Florence Birol, Pascal Bonnefond, Marcello Passaro, Fernando Nino, Rafael Almar, Olivier Laurain, Christian Schwatke, Jean-François Legeais, and Jérôme Benveniste
Ocean Sci., 16, 1165–1182, https://doi.org/10.5194/os-16-1165-2020, https://doi.org/10.5194/os-16-1165-2020, 2020
Short summary
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This study provides for the first time estimates of sea level anomalies very close to the coastline based on high-resolution retracked altimetry data, as well as corresponding sea level trends, over a 14-year time span. This new information has so far not been provided by standard altimetry data.
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Short summary
While a 6-year oscillation has been reported for some time in the motions of the fluid outer core of the Earth, in the magnetic field and in the Earth rotation, novel results indicate that the climate system also oscillates at this 6-year frequency. This strongly suggests the existence of coupling mechanisms affecting the Earth system as a whole, from the deep Earth interior to the surface fluid envelopes.
While a 6-year oscillation has been reported for some time in the motions of the fluid outer...
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