Articles | Volume 7, issue 3
https://doi.org/10.5194/wcd-7-1425-2026
© Author(s) 2026. 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-7-1425-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Synoptic drivers of the August 2024 record-breaking rainfall in the Chadian Sahara: dynamics, thermodynamics, and socio-economic consequences
Claudin Wamba Tchinda
CORRESPONDING AUTHOR
Climate Laboratory for Environmental Modeling and Atmospheric Physics (LEMAP), Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon
Fréderic Saha
Faculty of Arts, Letters and Social Sciences, University of Yaoundé 1, Yaoundé, Cameroon
Community Resilience Association (RESCOM-Tchad), Moundou, Chad
Alain Tchio Tamoffo
Climate Service Center Germany (GERICS), Helmholtz-Zentrum Hereon, Hamburg, Germany
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Hermann N. Nana, Masilin Gudoshava, Roméo S. Tanessong, Alain T. Tamoffo, and Derbetini A. Vondou
Weather Clim. Dynam., 6, 741–756, https://doi.org/10.5194/wcd-6-741-2025, https://doi.org/10.5194/wcd-6-741-2025, 2025
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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.
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
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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.
Fréderic Saha, Mesmin Tchindjang, Jean-Guy Dzana, and Djasrabé Nguemadjita
Proc. IAHS, 384, 241–246, https://doi.org/10.5194/piahs-384-241-2021, https://doi.org/10.5194/piahs-384-241-2021, 2021
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The flows of Logone and Chari allow to highlight successive hydro-climatic conditions in the Sahelian zone of Cameroon over the study period. In Bongor, the Qmin experienced three successive breaks, in 1971–72, 1998–99 and 2010–11. In N'Djamena, only one break occurred in 1982–83. From 2000, conditions became particularly contrasted. Only 23 % of catastrophic floods registered in the study area occurred during wet years. This shows the important role played by other factors.
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Short summary
Northern Chad's hydro-climatic regime has shifted since 2003 from aridity to heavy rain, peaking in August 2024. This resulted from Hadley cell reorganization, pushing the convective band northward. The West African monsoon reached deeper, replacing Saharan subsidence with moisture from the Gulf of Guinea. This thermodynamic change boosted moist static energy, enabling vertical ascent. Coupled with easterly waves, this created immense rainfall, altering Lake Chad’s water balance.
Northern Chad's hydro-climatic regime has shifted since 2003 from aridity to heavy rain, peaking...