Articles | Volume 4, issue 2
https://doi.org/10.5194/wcd-4-511-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wcd-4-511-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
14 Jun 2023
Research article |
| 14 Jun 2023
| 14 Jun 2023
Future changes in the mean and variability of extreme rainfall indices over the Guinea coast and role of the Atlantic equatorial mode
Earth and Climate Research Centre (TECLIM), Earth and Life Institute (ELI), Université catholique de Louvain (UCLouvain), Louvain-la-Neuve, Belgium
Thierry Fichefet
Earth and Climate Research Centre (TECLIM), Earth and Life Institute (ELI), Université catholique de Louvain (UCLouvain), Louvain-la-Neuve, Belgium
Hugues Goosse
Earth and Climate Research Centre (TECLIM), Earth and Life Institute (ELI), Université catholique de Louvain (UCLouvain), Louvain-la-Neuve, Belgium
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Over the Guinea Coast, the increased rainfall associated with warm phases of the Atlantic Niño is reasonably well simulated by 24 climate models out of 31, for the present-day conditions. In a warmer climate, general circulation models project a gradual decrease with time of the rainfall magnitude associated with the Atlantic Niño for the 2015–2039, 2040–2069 and 2070–2099 periods. There is a higher confidence in these changes over the equatorial Atlantic than over the Guinea Coast.
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EGUsphere, https://doi.org/10.5194/egusphere-2026-3552, https://doi.org/10.5194/egusphere-2026-3552, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
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How does increased horizontal resolution impact the skills of an ice-ocean numerical model to simulate sea ice in the Arctic and Antarctic? We address this question using the NEMO-SI3 model at three different resolutions. While some regional improvements are noticeable in winter in both Arctic and Antarctic, particularly where the ocean is known to influence sea ice, the overall added benefits of using a higher resolution are not systematic.
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EGUsphere, https://doi.org/10.5194/egusphere-2026-1823, https://doi.org/10.5194/egusphere-2026-1823, 2026
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The variability of the winter sea ice edge is much higher in regions close to the main topographic features of the Southern Ocean than over the smoother abyssal plain. The oceanic bathymetry influences mesoscale eddy activity and the Antarctic Circumpolar Current jets, affecting both oceanic heat transport and sea ice velocity and subsequently sea ice variability.
Ni Li, Wim Thiery, Shorouq Zahra, Mariana Madruga de Brito, Koffi Worou, Murathan Kurfalı, Seppe Lampe, Paul Muñoz, Clare Flynn, Camila Trigoso, Joakim Nivre, Jakob Zscheischler, and Gabriele Messori
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Jinfei Wang, Maike Sonnewald, Noé Pirlet, François Massonnet, Hugues Goosse, Dake Chen, and Qinghua Yang
EGUsphere, https://doi.org/10.5194/egusphere-2026-1301, https://doi.org/10.5194/egusphere-2026-1301, 2026
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Antarctic sea ice has shifted from expansion to rapid decline since 2016. Using model outputs and data mining, we identified six sea ice regimes, shaped by different dynamic and thermodynamic conditions. A coastal regime, featured by sea ice transport and new ice formation, has shown area loss since 1979, accelerating after 2016. This coastal regime and a pack ice regime together control overall sea ice variability. Our work offers a new framework for understanding Antarctic sea ice changes.
Benjamin Richaud, François Massonnet, Thierry Fichefet, Dániel Topál, Antoine Barthélemy, and David Docquier
The Cryosphere, 20, 791–810, https://doi.org/10.5194/tc-20-791-2026, https://doi.org/10.5194/tc-20-791-2026, 2026
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Sea ice covers in the Arctic and Antarctic experienced intense reduction during specific recent years. Using an ocean-sea ice model, we found similarities between hemispheres and years to explain the ice reduction, such as ice melt (or lack of growth) at the ice-ocean interface. Differences between years and regions are also evident, such as increased ice transport or snow precipitation. Our analysis highlights the importance of the ice-ocean interface to understand the sea ice mass budget.
Marie G. P. Cavitte, Hugues Goosse, Quentin Dalaiden, and Nicolas Ghilain
The Cryosphere, 19, 6483–6492, https://doi.org/10.5194/tc-19-6483-2025, https://doi.org/10.5194/tc-19-6483-2025, 2025
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Ice cores are influenced by local processes that alter SMB (surface mass balance) records. To evaluate if atmospheric circulation on large spatial scales can explain differing snowfall trends at 8 East Antarctic ice rises, we assimilated their ice core SMB records within a high-resolution downscaled atmospheric model with quantified local errors from radar constraints. The reconstruction captures the SMB records’ variability but may over-fit by introducing unrealistic spatial heterogeneity.
Emile Neimry, Hugues Goosse, and Mathieu Jonard
EGUsphere, https://doi.org/10.5194/egusphere-2025-5490, https://doi.org/10.5194/egusphere-2025-5490, 2025
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This study examines 180 years of drought variability in western Central Europe and its links to atmospheric circulation using three evaluated reanalysis datasets. Results reveal strong multidecadal variability, winter wetting, summer drying, and a growing influence of atmospheric evaporative demand. Four circulation patterns are identified, with recent droughts increasingly tied to the European High, marking a shift toward dynamics that intensify drought under climate change.
Hugues Goosse, Stephy Libera, Alberto C. Naveira Garabato, Benjamin Richaud, Alessandro Silvano, and Martin Vancoppenolle
The Cryosphere, 19, 5763–5779, https://doi.org/10.5194/tc-19-5763-2025, https://doi.org/10.5194/tc-19-5763-2025, 2025
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The position of the winter sea ice edge in the Southern Ocean is strongly linked to the one of the Antarctic Circumpolar Current and thus to ocean bathymetry. This is due to the influence of the Antarctic Circumpolar Current on the southward heat flux that limits sea ice expansion, directly through oceanic processes and indirectly through its influence on atmospheric heat transport.
Ting-Chen Chen, Hugues Goosse, Cécile Davrinche, Stephy Libera, Christopher Roberts, Matthias Aengenheyster, Kristian Strommen, Malcolm Roberts, Rohit Ghosh, and Jin-Song von Storch
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Annelies Sticker, François Massonnet, Thierry Fichefet, Patricia DeRepentigny, Alexandra Jahn, David Docquier, Christopher Wyburn-Powell, Daphne Quint, Erica Shivers, and Makayla Ortiz
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Florian Sauerland, Pierre-Vincent Huot, Sylvain Marchi, Thierry Fichefet, Hugues Goosse, Konstanze Haubner, François Klein, François Massonnet, Bianca Mezzina, Eduardo Moreno-Chamarro, Pablo Ortega, Frank Pattyn, Charles Pelletier, Deborah Verfaillie, Lars Zipf, and Nicole van Lipzig
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Bianca Mezzina, Hugues Goosse, François Klein, Antoine Barthélemy, and François Massonnet
The Cryosphere, 18, 3825–3839, https://doi.org/10.5194/tc-18-3825-2024, https://doi.org/10.5194/tc-18-3825-2024, 2024
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Marie G. P. Cavitte, Hugues Goosse, Kenichi Matsuoka, Sarah Wauthy, Vikram Goel, Rahul Dey, Bhanu Pratap, Brice Van Liefferinge, Thamban Meloth, and Jean-Louis Tison
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The net accumulation of snow over Antarctica is key for assessing current and future sea-level rise. Ice cores record a noisy snowfall signal to verify model simulations. We find that ice core net snowfall is biased to lower values for ice rises and the Dome Fuji site (Antarctica), while the relative uncertainty in measuring snowfall increases rapidly with distance away from the ice core sites at the ice rises but not at Dome Fuji. Spatial variation in snowfall must therefore be considered.
Steve Delhaye, Rym Msadek, Thierry Fichefet, François Massonnet, and Laurent Terray
EGUsphere, https://doi.org/10.5194/egusphere-2023-1748, https://doi.org/10.5194/egusphere-2023-1748, 2023
Preprint archived
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Mukesh Gupta, Leandro Ponsoni, Jean Sterlin, François Massonnet, and Thierry Fichefet
EGUsphere, https://doi.org/10.5194/egusphere-2023-1560, https://doi.org/10.5194/egusphere-2023-1560, 2023
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Elizabeth R. Thomas, Diana O. Vladimirova, Dieter R. Tetzner, B. Daniel Emanuelsson, Nathan Chellman, Daniel A. Dixon, Hugues Goosse, Mackenzie M. Grieman, Amy C. F. King, Michael Sigl, Danielle G. Udy, Tessa R. Vance, Dominic A. Winski, V. Holly L. Winton, Nancy A. N. Bertler, Akira Hori, Chavarukonam M. Laluraj, Joseph R. McConnell, Yuko Motizuki, Kazuya Takahashi, Hideaki Motoyama, Yoichi Nakai, Franciéle Schwanck, Jefferson Cardia Simões, Filipe Gaudie Ley Lindau, Mirko Severi, Rita Traversi, Sarah Wauthy, Cunde Xiao, Jiao Yang, Ellen Mosely-Thompson, Tamara V. Khodzher, Ludmila P. Golobokova, and Alexey A. Ekaykin
Earth Syst. Sci. Data, 15, 2517–2532, https://doi.org/10.5194/essd-15-2517-2023, https://doi.org/10.5194/essd-15-2517-2023, 2023
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Nathaelle Bouttes, Fanny Lhardy, Aurélien Quiquet, Didier Paillard, Hugues Goosse, and Didier M. Roche
Clim. Past, 19, 1027–1042, https://doi.org/10.5194/cp-19-1027-2023, https://doi.org/10.5194/cp-19-1027-2023, 2023
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Xia Lin, François Massonnet, Thierry Fichefet, and Martin Vancoppenolle
The Cryosphere, 17, 1935–1965, https://doi.org/10.5194/tc-17-1935-2023, https://doi.org/10.5194/tc-17-1935-2023, 2023
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This study provides clues on how improved atmospheric reanalysis products influence sea ice simulations in ocean–sea ice models. The summer ice concentration simulation in both hemispheres can be improved with changed surface heat fluxes. The winter Antarctic ice concentration and the Arctic drift speed near the ice edge and the ice velocity direction simulations are improved with changed wind stress. The radiation fluxes and winds in atmospheric reanalyses are crucial for sea ice simulations.
Andrew P. Schurer, Gabriele C. Hegerl, Hugues Goosse, Massimo A. Bollasina, Matthew H. England, Michael J. Mineter, Doug M. Smith, and Simon F. B. Tett
Clim. Past, 19, 943–957, https://doi.org/10.5194/cp-19-943-2023, https://doi.org/10.5194/cp-19-943-2023, 2023
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We adopt an existing data assimilation technique to constrain a model simulation to follow three important modes of variability, the North Atlantic Oscillation, El Niño–Southern Oscillation and the Southern Annular Mode. How it compares to the observed climate is evaluated, with improvements over simulations without data assimilation found over many regions, particularly the tropics, the North Atlantic and Europe, and discrepancies with global cooling following volcanic eruptions are reconciled.
Hugues Goosse, Sofia Allende Contador, Cecilia M. Bitz, Edward Blanchard-Wrigglesworth, Clare Eayrs, Thierry Fichefet, Kenza Himmich, Pierre-Vincent Huot, François Klein, Sylvain Marchi, François Massonnet, Bianca Mezzina, Charles Pelletier, Lettie Roach, Martin Vancoppenolle, and Nicole P. M. van Lipzig
The Cryosphere, 17, 407–425, https://doi.org/10.5194/tc-17-407-2023, https://doi.org/10.5194/tc-17-407-2023, 2023
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Using idealized sensitivity experiments with a regional atmosphere–ocean–sea ice model, we show that sea ice advance is constrained by initial conditions in March and the retreat season is influenced by the magnitude of several physical processes, in particular by the ice–albedo feedback and ice transport. Atmospheric feedbacks amplify the response of the winter ice extent to perturbations, while some negative feedbacks related to heat conduction fluxes act on the ice volume.
Pepijn Bakker, Hugues Goosse, and Didier M. Roche
Clim. Past, 18, 2523–2544, https://doi.org/10.5194/cp-18-2523-2022, https://doi.org/10.5194/cp-18-2523-2022, 2022
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Natural climate variability plays an important role in the discussion of past and future climate change. Here we study centennial temperature variability and the role of large-scale ocean circulation variability using different climate models, geological reconstructions and temperature observations. Unfortunately, uncertainties in models and geological reconstructions are such that more research is needed before we can describe the characteristics of natural centennial temperature variability.
Guillian Van Achter, Thierry Fichefet, Hugues Goosse, and Eduardo Moreno-Chamarro
The Cryosphere, 16, 4745–4761, https://doi.org/10.5194/tc-16-4745-2022, https://doi.org/10.5194/tc-16-4745-2022, 2022
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We investigate the changes in ocean–ice interactions in the Totten Glacier area between the last decades (1995–2014) and the end of the 21st century (2081–2100) under warmer climate conditions. By the end of the 21st century, the sea ice is strongly reduced, and the ocean circulation close to the coast is accelerated. Our research highlights the importance of including representations of fast ice to simulate realistic ice shelf melt rate increase in East Antarctica under warming conditions.
Nidheesh Gangadharan, Hugues Goosse, David Parkes, Heiko Goelzer, Fabien Maussion, and Ben Marzeion
Earth Syst. Dynam., 13, 1417–1435, https://doi.org/10.5194/esd-13-1417-2022, https://doi.org/10.5194/esd-13-1417-2022, 2022
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We describe the contributions of ocean thermal expansion and land-ice melting (ice sheets and glaciers) to global-mean sea-level (GMSL) changes in the Common Era. The mass contributions are the major sources of GMSL changes in the pre-industrial Common Era and glaciers are the largest contributor. The paper also describes the current state of climate modelling, uncertainties and knowledge gaps along with the potential implications of the past variabilities in the contemporary sea-level rise.
Jeanne Rezsöhazy, Quentin Dalaiden, François Klein, Hugues Goosse, and Joël Guiot
Clim. Past, 18, 2093–2115, https://doi.org/10.5194/cp-18-2093-2022, https://doi.org/10.5194/cp-18-2093-2022, 2022
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Using statistical tree-growth proxy system models in the data assimilation framework may have limitations. In this study, we successfully incorporate the process-based dendroclimatic model MAIDEN into a data assimilation procedure to robustly compare the outputs of an Earth system model with tree-ring width observations. Important steps are made to demonstrate that using MAIDEN as a proxy system model is a promising way to improve large-scale climate reconstructions with data assimilation.
Steve Delhaye, Thierry Fichefet, François Massonnet, David Docquier, Rym Msadek, Svenya Chripko, Christopher Roberts, Sarah Keeley, and Retish Senan
Weather Clim. Dynam., 3, 555–573, https://doi.org/10.5194/wcd-3-555-2022, https://doi.org/10.5194/wcd-3-555-2022, 2022
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It is unclear how the atmosphere will respond to a retreat of summer Arctic sea ice. Much attention has been paid so far to weather extremes at mid-latitude and in winter. Here we focus on the changes in extremes in surface air temperature and precipitation over the Arctic regions in summer during and following abrupt sea ice retreats. We find that Arctic sea ice loss clearly shifts the extremes in surface air temperature and precipitation over terrestrial regions surrounding the Arctic Ocean.
Nicolas Ghilain, Stéphane Vannitsem, Quentin Dalaiden, Hugues Goosse, Lesley De Cruz, and Wenguang Wei
Earth Syst. Sci. Data, 14, 1901–1916, https://doi.org/10.5194/essd-14-1901-2022, https://doi.org/10.5194/essd-14-1901-2022, 2022
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Modeling the climate at high resolution is crucial to represent the snowfall accumulation over the complex orography of the Antarctic coast. While ice cores provide a view constrained spatially but over centuries, climate models can give insight into its spatial distribution, either at high resolution over a short period or vice versa. We downscaled snowfall accumulation from climate model historical simulations (1850–present day) over Dronning Maud Land at 5.5 km using a statistical method.
Koffi Worou, Hugues Goosse, Thierry Fichefet, and Fred Kucharski
Earth Syst. Dynam., 13, 231–249, https://doi.org/10.5194/esd-13-231-2022, https://doi.org/10.5194/esd-13-231-2022, 2022
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Over the Guinea Coast, the increased rainfall associated with warm phases of the Atlantic Niño is reasonably well simulated by 24 climate models out of 31, for the present-day conditions. In a warmer climate, general circulation models project a gradual decrease with time of the rainfall magnitude associated with the Atlantic Niño for the 2015–2039, 2040–2069 and 2070–2099 periods. There is a higher confidence in these changes over the equatorial Atlantic than over the Guinea Coast.
Charles Pelletier, Thierry Fichefet, Hugues Goosse, Konstanze Haubner, Samuel Helsen, Pierre-Vincent Huot, Christoph Kittel, François Klein, Sébastien Le clec'h, Nicole P. M. van Lipzig, Sylvain Marchi, François Massonnet, Pierre Mathiot, Ehsan Moravveji, Eduardo Moreno-Chamarro, Pablo Ortega, Frank Pattyn, Niels Souverijns, Guillian Van Achter, Sam Vanden Broucke, Alexander Vanhulle, Deborah Verfaillie, and Lars Zipf
Geosci. Model Dev., 15, 553–594, https://doi.org/10.5194/gmd-15-553-2022, https://doi.org/10.5194/gmd-15-553-2022, 2022
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We present PARASO, a circumpolar model for simulating the Antarctic climate. PARASO features five distinct models, each covering different Earth system subcomponents (ice sheet, atmosphere, land, sea ice, ocean). In this technical article, we describe how this tool has been developed, with a focus on the
coupling interfacesrepresenting the feedbacks between the distinct models used for contribution. PARASO is stable and ready to use but is still characterized by significant biases.
Xia Lin, François Massonnet, Thierry Fichefet, and Martin Vancoppenolle
Geosci. Model Dev., 14, 6331–6354, https://doi.org/10.5194/gmd-14-6331-2021, https://doi.org/10.5194/gmd-14-6331-2021, 2021
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This study introduces a new Sea Ice Evaluation Tool (SITool) to evaluate the model skills on the bipolar sea ice simulations by providing performance metrics and diagnostics. SITool is applied to evaluate the CMIP6 OMIP simulations. By changing the atmospheric forcing from CORE-II to JRA55-do data, many aspects of sea ice simulations are improved. SITool will be useful for helping teams managing various versions of a sea ice model or tracking the time evolution of model performance.
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Short summary
The Atlantic equatorial mode (AEM) of variability is partly responsible for the year-to-year rainfall variability over the Guinea coast. We used the current climate models to explore the present-day and future links between the AEM and the extreme rainfall indices over the Guinea coast. Under future global warming, the total variability of the extreme rainfall indices increases over the Guinea coast. However, the future impact of the AEM on extreme rainfall events decreases over the region.
The Atlantic equatorial mode (AEM) of variability is partly responsible for the year-to-year...
