Articles | Volume 6, issue 3
https://doi.org/10.5194/wcd-6-741-2025
© 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/wcd-6-741-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Jul 2025
Research article |
| 11 Jul 2025
| 11 Jul 2025
Diverse causes of extreme rainfall in November 2023 over Equatorial Africa
Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Physics Department, University of Yaounde 1, P.O. Box 812, Yaounde, Cameroon
Masilin Gudoshava
IGAD Climate Prediction and Applications Centre (ICPAC), Nairobi, Kenya
Roméo S. Tanessong
Department of Meteorology and Climatology, Higher Institute of Agriculture, Forestry, Water and Environment, University of Ebolowa, P.O. Box 118, Ebolowa, Cameroon
Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Physics Department, University of Yaounde 1, P.O. Box 812, Yaounde, Cameroon
Alain T. Tamoffo
Climate Service Center Germany (GERICS), Helmholtz-Zentrum Hereon, Fischertwiete 1, 20095 Hamburg, Germany
Derbetini A. Vondou
Laboratory for Environmental Modelling and Atmospheric Physics (LEMAP), Physics Department, University of Yaounde 1, P.O. Box 812, Yaounde, Cameroon
Related authors
Hermann N. Nana, Roméo S. Tanessong, Masilin Gudoshava, and Derbetini A. Vondou
EGUsphere, https://doi.org/10.5194/egusphere-2025-2656, https://doi.org/10.5194/egusphere-2025-2656, 2025
This preprint is open for discussion and under review for Natural Hazards and Earth System Sciences (NHESS).
Short summary
Short summary
The results of this study reveal that the seasonal forecast model used here successfully reproduces the observed annual precipitation cycle and seasonal spatial pattern of rainfall over the region for both September and August initial conditions, with notably better skills for September, compared to August. In addition, the model effectively captures the teleconnections between rainfall and tropical sea surface temperature, including the Indian Ocean dipole and El Niño-Southern Oscillation.
Hermann N. Nana, Roméo S. Tanessong, Masilin Gudoshava, and Derbetini A. Vondou
EGUsphere, https://doi.org/10.5194/egusphere-2025-2656, https://doi.org/10.5194/egusphere-2025-2656, 2025
This preprint is open for discussion and under review for Natural Hazards and Earth System Sciences (NHESS).
Short summary
Short summary
The results of this study reveal that the seasonal forecast model used here successfully reproduces the observed annual precipitation cycle and seasonal spatial pattern of rainfall over the region for both September and August initial conditions, with notably better skills for September, compared to August. In addition, the model effectively captures the teleconnections between rainfall and tropical sea surface temperature, including the Indian Ocean dipole and El Niño-Southern Oscillation.
Kevin Kenfack, Francesco Marra, Zéphirin Yepdo Djomou, Lucie Angennes Djiotang Tchotchou, Alain Tchio Tamoffo, and Derbetini Appolinaire Vondou
Weather Clim. Dynam., 5, 1457–1472, https://doi.org/10.5194/wcd-5-1457-2024, https://doi.org/10.5194/wcd-5-1457-2024, 2024
Short summary
Short summary
The results of this study show that moisture advection induced by horizontal wind anomalies and vertical moisture advection induced by vertical velocity anomalies were crucial mechanisms behind the anomalous October 2019 exceptional rainfall increase over western central Africa. The information we derive can be used to support risk assessment and management in the region and to improve our resilience to ongoing climate change.
Wilfran Moufouma-Okia, Debertini A. Vondou, and Richard JONES
Weather Clim. Dynam. Discuss., https://doi.org/10.5194/wcd-2020-38, https://doi.org/10.5194/wcd-2020-38, 2020
Preprint withdrawn
Short summary
Short summary
This work examines the fidelity to reproduce regional and global monsoons climatological features using the Met Office Unified Model (MetUM) third and fourth generations Global Atmosphere (GA3.0) and (GA4.0), two configurations of the HadGEM3 system developed for use across climate and weather time scales. GA3.0 largely captures global monsoon features, including the monsoon precipitation patterns. GA4.0 and GA3.0 results display a close similarity, and compares reasonably well against CMIP5.
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Short summary
The results of this study show that extreme rainfall in November 2023 over Equatorial Africa was controlled by several factors, including strong sea-surface-temperature anomalies in the Niño-3.4, North Tropical Atlantic, Equatorial Atlantic and Indian Ocean Dipole regions; changes in zonal winds; the Walker circulation; the moisture flux and its divergence; and the easterly jets. The information we derive can be used to support risk assessment in the region and to improve our resilience to ongoing climate change.
The results of this study show that extreme rainfall in November 2023 over Equatorial Africa was...
