Extreme precipitation events have substantial socioeconomic effects due to their frequency and intensity. However, predicting and mitigating its effects is difficult due to their influence on society. The present study aims to investigate the predictability of extreme summer precipitation days (EPDs) over West Africa (WA) from 1982 to 2022. Based on daily CHIRPS data spanning 41 years over WA, EPDs were defined using a 90th-percentile threshold at each grid point. A set of Physics-based Empirical (P-E) models is established using the selected predictors. The simultaneous lower boundary anomalies linked to each EPDs index were also analyzed and found that the increased EPDs over WA are accompanied by a Pacific Sea Surface Temperature (SST) impact on monsoon flow and the warming of the SST in the Tropical Atlantic Ocean and western tropical Pacific Ocean. The temporal correlation coefficient (TCC) skill of the cross-validated forecast is 0.80 when the P-E model is constructed using data from 1982 to 2011. The independent forecast determines a significant TCC skill with a 95% level of 0.50 for the remaining period.
References
[1]
Ajibola, F. O., & Afolayan, S. A. (2024). Impacts of Improved Horizontal Resolutions in the Simulations of Mean and Extreme Precipitation Using CMIP6 HighResMIP Models over West Africa. Environmental Monitoring and Assessment, 196, Article No. 328. https://doi.org/10.1007/s10661-024-12492-7
[2]
Akinsanola, A. A., & Zhou, W. (2020). Understanding the Variability of West African Summer Monsoon Rainfall: Contrasting Tropospheric Features and Monsoon Index. Atmosphere, 11, Article 309. https://doi.org/10.3390/atmos11030309
[3]
Akinsanola, A. A., Ogunjobi, K. O., Gbode, I. E., & Ajayi, V. O. (2015). Assessing the Capabilities of Three Regional Climate Models over CORDEX Africa in Simulating West African Summer Monsoon Precipitation. Advances in Meteorology, 2015, Article ID: 935431. https://doi.org/10.1155/2015/935431
[4]
Akinyoola, J. A., Ajayi, V. O., Abiodun, B. J., Ogunjobi, K. O., Gbode, I. E., & Ogungbenro, S. B. (2019). Dynamic Response of Monsoon Precipitation to Mineral Dust Radiative Forcing in the West Africa Region. Modeling Earth Systems and Environment, 5, 1201-1214. https://doi.org/10.1007/s40808-019-00620-z
[5]
Berthou, S., Kendon, E. J., Rowell, D. P., Roberts, M. J., Tucker, S., & Stratton, R. A. (2019). Larger Future Intensification of Rainfall in the West African Sahel in a Convection-Permitting Model. Geophysical Research Letters, 46, 13299-13307. https://doi.org/10.1029/2019gl083544
[6]
de Coëtlogon, G., Deroubaix, A., Flamant, C., Menut, L., & Gaetani, M. (2023). Impact of the Guinea Coast Upwelling on Atmospheric Dynamics, Precipitation and Pollutant Transport over Southern West Africa. Atmospheric Chemistry and Physics, 23, 15507-15521. https://doi.org/10.5194/acp-23-15507-2023
[7]
Diatta, S., Diedhiou, C. W., Dione, D. M., & Sambou, S. (2020). Spatial Variation and Trend of Extreme Precipitation in West Africa and Teleconnections with Remote Indices. Atmosphere, 11, Article 999. https://doi.org/10.3390/atmos11090999
[8]
Diedhiou, C. W., Diatta, S., Ndione, D. M., & Sambou, S. (2020). Spatial Variation and Trend of Extreme Precipitation in West Africa and Teleconnections with Remote Indices. Atmosphere, 11, Article 999.
[9]
Ebiendele, P. E., & Adigun, P. A. (2022). Added Value of Bias Adjusted and Statistical Downscaled ISIMIP Models in Simulating Extreme Precipitation Characteristics over West Africa (pp. 1-28). https://www.researchsquare.com/article/rs-2028519/v1
[10]
Hamatan, M., Mahe, G., Servat, É., Paturel, J. E., & Amani, A. (2004). Synthèse et Évaluation Des Prévisions Saisonnières En Afrique de l’Ouest. Sécheresse, 15, 279-286.
[11]
Hounkpè, J., Badou, D. F., Bossa, A. Y., Yira, Y., Adounkpè, J., Alamou, E. A. et al. (2021). Assessment of Flood Discharge Sensitivity to Climate Indexes in West Africa. Proceedings of the International Association of Hydrological Sciences, 384, 219-224. https://doi.org/10.5194/piahs-384-219-2021
[12]
Jones, C., Waliser, D. E., Lau, K. M., & Stern, W. (2004). Global Occurrences of Extreme Precipitation and the Madden-Julian Oscillation: Observations and Predictability. Journal of Climate, 17, 4575-4589. https://doi.org/10.1175/3238.1
[13]
Klutse, N. A. B., Abiodun, B. J., Quagraine, K. A., Nkrumah, F., Abaton, A. A., Adekoke, J. et al. (2024). Projected Changes in Rainfall Extremes over West African Cities under Specific Global Warming Levels Using CORDEX and NEX-GDDP Datasets. Earth Systems and Environment, 8, 747-764. https://doi.org/10.1007/s41748-024-00425-w
[14]
Li, J., & Wang, B. (2016). How Predictable Is the Anomaly Pattern of the Indian Summer Rainfall? Climate Dynamics, 46, 2847-2861. https://doi.org/10.1007/s00382-015-2735-6
[15]
Li, J., & Wang, B. (2018). Predictability of Summer Extreme Precipitation Days over Eastern China. Climate Dynamics, 51, 4543-4554. https://doi.org/10.1007/s00382-017-3848-x
[16]
Li, J., Qian, Y., Leung, L. R., & Feng, Z. (2021). Summer Mean and Extreme Precipitation over the Mid-Atlantic Region: Climatological Characteristics and Contributions from Different Precipitation Types. Journal of Geophysical Research: Atmospheres, 126, e2021JD035045. https://doi.org/10.1029/2021jd035045
[17]
Maurer, V., Kalthoff, N., & Gantner, L. (2017). Predictability of Convective Precipitation for West Africa: Verification of Convection-Permitting and Global Ensemble Simulations. Meteorologische Zeitschrift, 26, 93-110. https://doi.org/10.1127/metz/2016/0728
[18]
Mohino, E., Monerie, P. A., Mignot, J., Diakhaté, M., Donat, M., Roberts, C. D., & Doblas-Reyes, F. (2023). Impact of AMV on Rainfall Intensity Distribution and Timing of the West African Monsoon in DCPP-C-Like Simulations.
[19]
Mubark, A., Chen, Q., Abdallah, M., Hussien, A., & Hamadalnel, M. (2024). Projection of Extreme Summer Precipitation over Hubei Province in the 21st Century. Atmosphere, 15, Article 983. https://doi.org/10.3390/atmos15080983
[20]
Ndehedehe, C. E., Usman, M., Okwuashi, O., & Ferreira, V. G. (2022). Modelling Impacts of Climate Change on Coastal West African Rainfall. Modeling Earth Systems and Environment, 8, 3325-3340. https://doi.org/10.1007/s40808-021-01302-5
[21]
Panthou, G., Vischel, T., & Lebel, T. (2014). Recent Trends in the Regime of Extreme Rainfall in the Central Sahel. International Journal of Climatology, 34, 3998-4006. https://doi.org/10.1002/joc.3984
[22]
Quagraine, K. A., Nkrumah, F., Klein, C., Klutse, N. A. B., & Quagraine, K. T. (2020). West African Summer Monsoon Precipitation Variability as Represented by Reanalysis Datasets. Climate, 8, Article 111. https://doi.org/10.3390/cli8100111
[23]
Rodríguez-Fonseca, B., Mohino, E., Mechoso, C. R., Caminade, C., Biasutti, M., Gaetani, M. et al. (2015). Variability and Predictability of West African Droughts: A Review on the Role of Sea Surface Temperature Anomalies. Journal of Climate, 28, 4034-4060. https://doi.org/10.1175/jcli-d-14-00130.1
[24]
Salack, S., Saley, I. A., Lawson, N. Z., Zabré, I., & Daku, E. K. (2018). Scales for Rating Heavy Rainfall Events in the West African Sahel. Weather and Climate Extremes, 21, 36-42. https://doi.org/10.1016/j.wace.2018.05.004
[25]
Ta, S., Kouadio, K. Y., Ali, K. E., Toualy, E., Aman, A., & Yoroba, F. (2016). West Africa Extreme Rainfall Events and Large-Scale Ocean Surface and Atmospheric Conditions in the Tropical Atlantic. Advances in Meteorology, 2016, Article ID: 1940456. https://doi.org/10.1155/2016/1940456
[26]
Tabari, H. (2020). Climate Change Impact on Flood and Extreme Precipitation Increases with Water Availability. Scientific Reports, 10, Article No. 13768. https://doi.org/10.1038/s41598-020-70816-2
[27]
Thomas, R. K., Gerald, A. M., Christopher, D. M., & William, L. M. (2008). Weather and Climate Extremes in a Changing Climate Regions of Focus. https://www.sdr.gov/pdfs/Presentations/CCSP_SAP3_3_WeatherAndClimateExtremesInAChangingClimate.pdf
[28]
Tore, D. B., Alamou, A. E., Obada, E., Biao, E. I., & Zandagba, E. B. J. (2022). Assessment of Intra-Seasonal Variability and Trends of Precipitations in a Climate Change Framework in West Africa. Atmospheric and Climate Sciences, 12, 150-171. https://doi.org/10.4236/acs.2022.121011
[29]
Vizy, E. K., & Cook, K. H. (2022). Distribution of Extreme Rainfall Events and Their Environmental Controls in the West African Sahel and Soudan. Climate Dynamics, 59, 997-1026. https://doi.org/10.1007/s00382-022-06171-x
[30]
Worou, K., Fichefet, T., & Goosse, H. (2022). Future Changes in the Mean and Variability of Extreme Rainfall Indices over the Guinea Coast and Role of the Atlantic Equatorial Mode. Weather and Climate Dynamics, 4, 511-530.
[31]
Zhou, Z., Li, J., Chen, H., & Zhu, Z. (2023). Seasonal Prediction of Extreme High-Temperature Days in Southwestern China Based on the Physical Precursors. Advances in Atmospheric Sciences, 40, 1212-1224. https://doi.org/10.1007/s00376-022-2075-5
