We analysed nine simulations from dynamic downscaling to a horizontal resolution of approximately 25 km of three general circulation models (GCMs). These GCMs use three regional climate models (RCMs) that participated in the coordinated downscaling experiment (CORDEX-CORE). These simulations were compared to three datasets of reanalysis. The ERA5 for temperature at 2 metres and for precipitation, Climate Hazards Center InfraRed Precipitation with Stations (CHIRPS) and African Rainfall Climatology from the Famine Early Warning System (FEWS-ARC) were used. To give an overview of these nine model experiments, we presented and compared the results of the latter with the reanalysis taken into account for the period 1983 - 2005. The results indicated that the nine models correctly reproduced the temperature and rainfall in West Africa during the historical period. In the Guinean coast region, REMO-NorESM1 and RegCM4-MPI-MR models well simulated precipitation and temperature during the historical period. In the Savannah region, RegCM4-NorESM1, CCLM5-MPI-LR, REMO-NorESM1, CCLM5-NorESM1 and CCLM5-HadGEM2 model gave best result. In the Sahel region, the RegCM4-HadGEM2 model gave a good correlation. Using the Taylor diagram in the historical period, all CORDEX-CORE RCMs had a strong relationship with temperature.
References
[1]
Akinsanola, A. A., & Ogunjobi, K. O. (2017). Evaluation of Present-Day Rainfall Simulations over West Africa in CORDEX Regional Climate Models. Environmental Earth Sciences, 76, Article No. 366. https://doi.org/10.1007/s12665-017-6691-9
[2]
Betant, C. A., Weber, T., Hoffmann, P., Ndao, S., Ngongang, R. D., Meukaleuni, C. et al. (2024). Model Analysis of Coastal and Continental Impacts on Boundary Layer Meteorology over West Africa. Earth Systems and Environment, 8, 783-799. https://doi.org/10.1007/s41748-024-00428-7
[3]
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S. et al. (2011). The Era‐interim Reanalysis: Configuration and Performance of the Data Assimilation System. Quarterly Journal of the Royal Meteorological Society, 137, 553-597. https://doi.org/10.1002/qj.828
[4]
Dia-Diop, A., Zebaze, S., Wade, M., Djiondo, R. N., Diop, B., Efon, E. et al. (2020). Interannual Variability of Rainfall over the West Africa Sahel. Journal of Geoscience and Environment Protection, 8, 85-101. https://doi.org/10.4236/gep.2020.83007
[5]
Diallo, I., Sylla, M. B., Camara, M., & Gaye, A. T. (2012). Interannual Variability of Rainfall over the Sahel Based on Multiple Regional Climate Models Simulations. Theoretical and Applied Climatology, 113, 351-362. https://doi.org/10.1007/s00704-012-0791-y
[6]
Dike, V. N., Lin, Z., Fei, K., Langendijk, G. S., & Nath, D. (2022). Evaluation and Multimodel Projection of Seasonal Precipitation Extremes over Central Asia Based on CMIP6 Simulations. International Journal of Climatology, 42, 7228-7251. https://doi.org/10.1002/joc.7641
[7]
Endris, H. S., Omondi, P., Jain, S., Lennard, C., Hewitson, B., Chang’a, L. et al. (2013). Assessment of the Performance of CORDEX Regional Climate Models in Simulating East African Rainfall. Journal of Climate, 26, 8453-8475. https://doi.org/10.1175/jcli-d-12-00708.1
[8]
Fotso-Nguemo, T. C., Vondou, D. A., Tchawoua, C., & Haensler, A. (2017). Assessment of Simulated Rainfall and Temperature from the Regional Climate Model REMO and Future Changes over Central Africa. Climate Dynamics, 48, 3685-3705. https://doi.org/10.1007/s00382-016-3294-1
[9]
Giorgi, F., Jones, C., & Asrar, G. R. (2009). Addressing Climate Information Needs at the Regional Level: The CORDEX Framework. WMO Bulletin, 58, 175-183
[10]
Herman, J. R., Bhartia, P. K., Torres, O., Hsu, C., Seftor, C., & Celarier, E. (1997). Global Distribution of UV-Absorbing Aerosols from Nimbus 7/TOMS Data, Journal of Geophysical Research, 102, 16911-16922. https://doi.org/10.1029/96JD03680
[11]
Ilori, O. W., & Ajayi, V. O. (2020). Change Detection and Trend Analysis of Future Temperature and Rainfall over West Africa. Earth Systems and Environment, 4, 493-512. https://doi.org/10.1007/s41748-020-00174-6
[12]
Ilori, O. W., & Balogun, I. A. (2022). Evaluating the Performance of New Cordex-Africa Regional Climate Models in Simulating West African Rainfall. Modeling Earth Systems and Environment, 8, 665-688. https://doi.org/10.1007/s40808-021-01084-w
[13]
IPCC (2023). Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (p. 184). IPCC.
[14]
Kalognomou, E., Lennard, C., Shongwe, M., Pinto, I., Favre, A., Kent, M. et al. (2013). A Diagnostic Evaluation of Precipitation in CORDEX Models over Southern Africa. Journal of Climate, 26, 9477-9506. https://doi.org/10.1175/jcli-d-12-00703.1
[15]
Kendall, M. G. (1975). Rank Correlation Methods. Griffin.
[16]
Klutse, N. A. B., Sylla, M. B., Diallo, I., Sarr, A., Dosio, A., Diedhiou, A. et al. (2016). Daily Characteristics of West African Summer Monsoon Precipitation in CORDEX Simulations. Theoretical and Applied Climatology, 123, 369-386. https://doi.org/10.1007/s00704-014-1352-3
[17]
Kouassi, A. M., Kouao, J., & Kouakou, K. E. (2022). Caractérisation intra-annuelle de la variabilité climatique en Côte d’Ivoire. Bulletin de l’Association de géographes français, 99, 289-306. https://doi.org/10.4000/bagf.9534
[18]
Le Barbé, L., Lebel, T., & Tapsoba, D. (2002). Rainfall Variability in West Africa during the Years 1950-90. Journal of Climate, 15, 187-202. https://doi.org/10.1175/1520-0442(2002)015<0187:rviwad>2.0.co;2
[19]
Lenouo, A., Pokam, W., Vondou, A. D., Janicot, S., & Mkankam, F. K. (2021). Variability of the Rain Belt in Western Central Africa. In C. P. Chang (Ed.), World Scientific Series on Asia-Pacific Weather and Climate (pp. 67-78). World Scientific. https://doi.org/10.1142/9789811216602_0006
[20]
Lenouo, A., Sall, S. M., Badiane, D., Gaye, A. T., & Kamga Mkankam, F. (2016). Intense Convection over West Africa during AMMA SOP3 Experiment. Atmospheric Research, 180, 1-11. https://doi.org/10.1016/j.atmosres.2016.05.002
[21]
Mann, H. B. (1945). Nonparametric Tests against Trend. Econometrica, 13, 245-259. https://doi.org/10.2307/1907187
[22]
Mbouna, A. D., Tamoffo, A. T., Asare, E. O., Lenouo, A., & Tchawoua, C. (2022). Malaria Metrics Distribution under Global Warming: Assessment of the VECTRI Malaria Model over Cameroon. International Journal of Biometeorology, 67, 93-105. https://doi.org/10.1007/s00484-022-02388-x
[23]
Ndao, S., Lenouo, A., Badiane, D., Penka, M., Tchawoua, C., Sall, S. M. et al. (2020). Climatology of West Africa Boundary Layer. Terrestrial, Atmospheric and Oceanic Sciences, 31, 619-632. https://doi.org/10.3319/tao.2020.04.21.01
[24]
Ndao, S., Rinelle, D. N., Badiane, D., Lenouo, A., & Sall, S. M. (2019). Study of Boundary Layer Height over West Africa. Journal of Geoscience and Environment Protection, 7, 179-194. https://doi.org/10.4236/gep.2019.711013
[25]
Nicholson, S. E. (2013). The West African Sahel: A Review of Recent Studies on the Rainfall Regime and Its Interannual Variability. ISRN Meteorology, 2013, 1-32. https://doi.org/10.1155/2013/453521
[26]
Nikulin, G., Jones, C., Giorgi, F., Asrar, G., Buchner, M., Cerezo-Mota, R. et al. (2012). Precipitation Climatology in an Ensemble of CORDEX-Africa Regional Climate Simulations. Journal of Climate, 25, 6057-6078. https://doi.org/10.1175/JCLI-D-11-00375.1
[27]
Novella, N. S., & Thiaw, W. M. (2013). African Rainfall Climatology Version 2 for Famine Early Warning Systems. Journal of Applied Meteorology and Climatology, 52, 588-606. https://doi.org/10.1175/jamc-d-11-0238.1
[28]
Omotosho, J., & Abiodun, B. J. (2007). A Numerical Study of Moisture Build-Up and Rainfall over West Africa. Meteorological Applications, 14, 209-225. https://doi.org/10.1002/met.11
[29]
Remedio, A. R., Teichmann, C., Buntemeyer, L., Sieck, K., Weber, T., Rechid, D. et al. (2019). Evaluation of New CORDEX Simulations Using an Updated Köppen-Trewartha Climate Classification. Atmosphere, 10, Article 726. https://doi.org/10.3390/atmos10110726
[30]
Safari, B., Sebaziga, J. N., & Siebert, A. (2022). Evaluation of Cordex-Core Regional Climate Models in Simulating Rainfall Variability in Rwanda. International Journal of Climatology, 43, 1112-1140. https://doi.org/10.1002/joc.7891
[31]
Schneider, R., Schmitt, J., Köhler, P., Joos, F., & Fischer, H. (2013). A Reconstruction of Atmospheric Carbon Dioxide and Its Stable Carbon Isotopic Composition from the Penultimate Glacial Maximum to the Last Glacial Inception. Climate of the Past, 9, 2507-2523. https://doi.org/10.5194/cp-9-2507-2013
[32]
Seetha, C. J., Mehta, S. K., Kakkanattu, S. P., Purushotham, P., Betsy, K. B., & Musaid, P. P. (2023). Characteristics of the Atmospheric Boundary Layer during Transient Conditions of the Indian Summer Monsoon. Theoretical and Applied Climatology, 154, 661-684. https://doi.org/10.1007/s00704-023-04578-y
[33]
Sultan, B., & Janicot, S. (2000). Abrupt Shift of the ITCZ over West Africa and Intra-Seasonal Variability. Geophysical Research Letters, 27, 3353-3356. https://doi.org/10.1029/1999gl011285
[34]
Sultan, B., Roudier, P., & Traoré, S. (2015). Chapitre 10. Les impacts du changement climatique sur les rendements agricoles en Afrique de l’Ouest. In S. Benjamin et al., (Eds.), Les sociétés rurales face aux changements climatiques et environnementaux en Afrique de l’Ouest (pp. 209-225). IRD Éditions. https://doi.org/10.4000/books.irdeditions.9773
[35]
Sylla, M. B., Diallo, I., & Pal, J. S. (2013). West African Monsoon in State of the Art Regional Climate Models. In A Tarhule (Ed.), Climate Variability-Regional and Thematic Patterns (Ch. 1-31). InTech Open.
[36]
Tamoffo, A. T., Dosio, A., Amekudzi, L. K., & Weber, T. (2022). Process-Oriented Evaluation of the West African Monsoon System in CORDEX-CORE Regional Climate Models. Climate Dynamics, 60, 3187-3210. https://doi.org/10.1007/s00382-022-06502-y
[37]
Tamoffo, A. T., Weber, T., Akinsanola, A. A., & Vondou, D. A. (2023). Projected Changes in Extreme Rainfall and Temperature Events and Possible Implications for Cameroon’s Socio-Economic Sectors. Meteorological Applications, 30, e2119. https://doi.org/10.1002/met.2119
[38]
Taylor, K. E. (2001). Summarizing Multiple Aspects of Model Performance in a Single Diagram. Journal of Geophysical Research: Atmospheres, 106, 7183-7192. https://doi.org/10.1029/2000jd900719
[39]
Wane, D., Dieng, A. L., Niang, C., & Gaye, A. T. (2023). Northeastern Tropical Atlantic SST and Sahel Rainfall Variability. Atmospheric and Climate Sciences, 13, 431-454. https://doi.org/10.4236/acs.2023.134024
[40]
Weber, T., Haensler, A., Rechid, D., Pfeifer, S., Eggert, B., & Jacob, D. (2018). Analyzing Regional Climate Change in Africa in a 1.5, 2, and 3˚C Global Warming World. Earth’s Future, 6, 643-655. https://doi.org/10.1002/2017ef000714
[41]
World Bank Report (2024). The World Bank 1818 H Street NW Washington DC 20433 USA. https://bit.ly/WBAR2024MainReportEN
[42]
Xie, P., & Arkin, P. A. (1996). Analyses of Global Monthly Precipitation Using Gauge Observations, Satellite Estimates, and Numerical Model Predictions. Journal of Climate, 9, 840-858. https://doi.org/10.1175/1520-0442(1996)009<0840:aogmpu>2.0.co;2
