Articles | Volume 14, issue 3
https://doi.org/10.5194/esd-14-685-2023
© 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/esd-14-685-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Past and future response of the North Atlantic warming hole to anthropogenic forcing
Saïd Qasmi
CORRESPONDING AUTHOR
CNRM, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Related authors
Rémy Bonnet and Saïd Qasmi
EGUsphere, https://doi.org/10.5194/egusphere-2026-6013, https://doi.org/10.5194/egusphere-2026-6013, 2026
This preprint is open for discussion and under review for Earth System Dynamics (ESD).
Short summary
Short summary
The Atlantic Ocean’s overturning circulation (AMOC) is expected to weaken as the climate warms, but large uncertainties remain. We use a Bayesian statistical method to assess whether direct and indirect AMOC observations can constrain its projected weakening. We find that this constraint is sensitive to internal variability, while longer observations could provide more robust estimates. All constraints indicate substantial weakening (~50%), with potentially strong climate impacts.
Enora Cariou, Julien Cattiaux, Saïd Qasmi, and Aurélien Ribes
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This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
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Europe has warmed rapidly in recent decades, partly due to changes in atmospheric circulation, but whether these circulation changes arise from natural variability or anthropogenic forcing remains unclear. Here, using neural network and statistical approaches, we quantify the forced and internal contributions to observed and projected dynamical changes. We further use this dynamical information to derive a new estimate of recent and future warming in Europe.
Aurélien Ribes, Julien Boé, Saïd Qasmi, Brigitte Dubuisson, Hervé Douville, and Laurent Terray
Earth Syst. Dynam., 13, 1397–1415, https://doi.org/10.5194/esd-13-1397-2022, https://doi.org/10.5194/esd-13-1397-2022, 2022
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We use a novel statistical method to combine climate simulations and observations, and we deliver an updated assessment of past and future warming over France. As a key result, we find that the warming over that region was underestimated in previous multi-model ensembles by up to 50 %. We also assess the contribution of greenhouse gases, aerosols, and other factors to the observed warming, as well as the impact on the seasonal temperature cycle, and we discuss implications for climate services.
Rémy Bonnet and Saïd Qasmi
EGUsphere, https://doi.org/10.5194/egusphere-2026-6013, https://doi.org/10.5194/egusphere-2026-6013, 2026
This preprint is open for discussion and under review for Earth System Dynamics (ESD).
Short summary
Short summary
The Atlantic Ocean’s overturning circulation (AMOC) is expected to weaken as the climate warms, but large uncertainties remain. We use a Bayesian statistical method to assess whether direct and indirect AMOC observations can constrain its projected weakening. We find that this constraint is sensitive to internal variability, while longer observations could provide more robust estimates. All constraints indicate substantial weakening (~50%), with potentially strong climate impacts.
Enora Cariou, Julien Cattiaux, Saïd Qasmi, and Aurélien Ribes
EGUsphere, https://doi.org/10.5194/egusphere-2026-5426, https://doi.org/10.5194/egusphere-2026-5426, 2026
This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
Short summary
Short summary
Europe has warmed rapidly in recent decades, partly due to changes in atmospheric circulation, but whether these circulation changes arise from natural variability or anthropogenic forcing remains unclear. Here, using neural network and statistical approaches, we quantify the forced and internal contributions to observed and projected dynamical changes. We further use this dynamical information to derive a new estimate of recent and future warming in Europe.
Aurélien Ribes, Julien Boé, Saïd Qasmi, Brigitte Dubuisson, Hervé Douville, and Laurent Terray
Earth Syst. Dynam., 13, 1397–1415, https://doi.org/10.5194/esd-13-1397-2022, https://doi.org/10.5194/esd-13-1397-2022, 2022
Short summary
Short summary
We use a novel statistical method to combine climate simulations and observations, and we deliver an updated assessment of past and future warming over France. As a key result, we find that the warming over that region was underestimated in previous multi-model ensembles by up to 50 %. We also assess the contribution of greenhouse gases, aerosols, and other factors to the observed warming, as well as the impact on the seasonal temperature cycle, and we discuss implications for climate services.
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Short summary
A new statistical method combining climate models and observations confirms the anthropogenic role in the cooling of the North Atlantic warming hole. Aerosols increase sea surface temperature (SST), while greenhouse gases contribute to the cooling over the 1870–2020 period. The method is able to reduce model uncertainty in the SST projections by 65% in the short term and up to 50% in the long term, excluding previous unlikely temperature increase scenarios.
A new statistical method combining climate models and observations confirms the anthropogenic...
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